Name: 497-23-4|Furan-2(5H)-one|97%
Brand: Ambeed
SKU: A134936
Price: 6.0 USD
Availability: InStock
Rating: 93 (22 reviews)

1
[ 1193-54-0 ]
[ 497-23-4 ]
[ 2972-17-0 ]

Reference： [1]Angewandte Chemie,1965,vol. 77,p. 452

2
[ 98-01-1 ]
[ 20825-71-2 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
1: 37% 2: 18%	With dihydrogen peroxide; sodium sulfate In 1,2-dichloro-ethane for 10h; Heating;
26%	With formic acid; dihydrogen peroxide; sodium sulfate In dichloromethane reflux, 3 h 45 min; cooling to room temp., 10 h;
	With formic acid; dihydrogen peroxide In methanol; water at 24.84℃; for 1h; Autoclave;	3.1. Catalytic conversion of furfural into BDO Furfural is oxidized with performic acid to give a mixture of2(5H)-furanone and its isomer (2(3H)-furanone) [28]. The directoxidation of furfural with formic acid/hydrogen peroxide canproceed without the catalyst and the yield of furanones is 43.2%after nine-hour reaction (Table 1). This conversion of furfural tofuranones is too slow to be synthetically useful. Supported Pt andPd show marked catalytic activity for improving the conversion(Fig. S1). The leaching of Pd in the acidic solution is serious andgradual deactivation is observed. In the oxidation of furfural withformic acid/hydrogen peroxide, supported Pt is the most suitablecatalysts. The residual peroxide after the oxidation is hazardous anddangerous to the following hydrogenation. Supported platinum cancatalyze the self-decomposition of peroxide under mild conditions.Table 1 lists experimental results about the conversion from fur-fural to BDO over supported platinum catalysts. The oxidation of furfural to furanones is performed by gradual addition of hydro-gen peroxide into the reaction mixture during 1.0 h. The residualperoxide is removed by self-decomposition over supported Pt cat-alysts. Pt/TiO2-ZrO2removes the residual peroxide within 25 min(Table 1). No residual peroxide is detected by a negative per-oxide test. The reaction mixture is further hydrogenated to giveBDO without any separation or purification. Pt/TiO2-ZrO2(Pt load:1.0 wt%) is the most active catalyst and the total yield of BDOreaches 85.2%.

With dihydrogen peroxide; sodium sulfate at 60 - 70℃; for 12h; Reflux;

Furan-2(3H)-one and Furan-2(5H)-one (SMI-172) The furanones SMI-172 were prepared using a reported procedure (Cao, R.; et al., A convenient synthesis of 2(5H)-Furanone. Organic Preparations and Procedures International 1996, 28, 215-216). To a 250 mL flask equipped with a stirring bar, was added furfural (14.40 g, 149.87 mmol), DCM (30 mL) and sodium sulfate (18.09 g, 127.39 mmol) at room temperature. Then 35% hydrogen peroxide (33 mL, 383.66 mmol) was added drop wise with stirring at 60 ~70 °C for 2 h. The mixture was refluxed for 10 h, cooled to room temperature and filtered. The aqueous layer was extracted with DCM (2 x 20 mL), the combined organic layers were dried (Na2S04), concentrated to give SMI-172 (6.88 g, 54%) as a red liquid. This was used in the next step without purification.

Reference： [1]Cao, Ruzhen; Diu, Chong; Liu, Lunzu [Organic Preparations and Procedures International, 1996, vol. 28, # 2, p. 215 - 216]
[2]Nasman; Pensar [Synthesis, 1985, vol. NO. 8, # 8, p. 786 - 788]
[3]Li, Fengbo; Lu, Tao; Chen, Bingfeng; Huang, Zhijun; Yuan, Guoqing [Applied Catalysis A: General, 2014, vol. 478, p. 252 - 258]
[4]Current Patent Assignee: H. LEE MOFFITT CANCER CENTER & RESEARCH INSTITUTE - WO2020/14489, 2020, A2 Location in patent: Page/Page column 66

3
[ 98-01-1 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
64%	With niobium(V) acetate tetrahydrate; dihydrogen peroxide In water at 60℃; for 84h;
62%	With formic acid; water; dihydrogen peroxide; sodium sulfate In ethyl acetate at 260℃; for 2.5h;	2 Example 2 Example 2Furfural oxidation reaction: 4.0 g of furfural, 4.0 g of anhydrous sodium sulfate, 1.5 ml of formic acid and 1.5 ml of deionized water were added to 10 ml of ethyl acetate, 10 ml of hydrogen peroxide (30%) was injected, and stirred at 60C under normal pressure The reaction was allowed to stand for 2.5 hours. After the reaction, the reaction mixture was allowed to stand. The organic phase was distilled under reduced pressure to obtain 62% yield of 2 (5H) -furanone and 15% yield of dibasic acid in aqueous phase.
58%	With 2-(N,N-dimethylamino)ethanol; formic acid; dihydrogen peroxide; sodium sulfate In dichloromethane; water at 20℃; for 15h; Inert atmosphere;

47%	With formic acid; dihydrogen peroxide; potassium carbonate; sodium sulfate In dichloromethane Reflux;	4.3. Procedure for the synthesis of TMSOF 2¹⁵ A 1-L three-necked flask, equipped with a reflux condenser and a dropping funnel, was charged with furfural (48 g, 0.5 mol), CH2Cl2 (250 mL), formic acid (46 g, 1.0 mol), Na2SO4 (50 g), and K2CO3 (17.5 g). The mixture was vigorously stirred and 30% H2O2 (38 mL) was added in one portion. Vigorous stirring was continued for 30-45 min after which refluxed gently. Then 30% H2O2 (63 mL) was added dropwise with continued stirring. The mixture was stirred overnight after cooling to room temperature. The organic phase was separated, and the aqueous layer was extracted with 50 mL CH2Cl2. The combined organic phase was concentrated in vacuo. 100 mL toluene was added and formic acid was removed by azeotropic distillation. Another 100 mL toluene was added to the reisdue, followed by 1.3 mL triethylamine, and the mixture was allowed to stand for 1 h. After toluene was evaporated, the residual liquid was distilled in vacuo to afford furanone (19.7 g, 47%) as colorless liquid at 63-66 °C/5.9 mmHg.To furanone (19.7 g, 0.142 mol) Et3N (36.0 mL, 0.26 mol) was added, followed by TMSCl (19.7 g, 0.235 mol) at 0 °C under N2. The reaction mixture was filtrated through silica gel, and the cake was washed with dry Et2O to give a clear filtrate. Fractional distillation under reduced pressure of the mixture afforded 2 (13.0 g, 58%) as a yellowish liquid
45%	With 2-(N,N-dimethylamino)ethanol; formic acid; dihydrogen peroxide
42%	With formic acid; dihydrogen peroxide; potassium carbonate; sodium sulfate In dichloromethane Inert atmosphere; Reflux;
41%	With 2-(N,N-dimethylamino)ethanol; formic acid; dihydrogen peroxide; sodium sulfate In dichloromethane; water Inert atmosphere;
40%	With Peroxyformic acid; dihydrogen peroxide; 2-(Diethylamino)ethanol
35%	With formic acid; dihydrogen peroxide; potassium carbonate; sodium sulfate In dichloromethane for 12h; Reflux;
23.8%	With 2,6-di-tert-butyl-4-methyl-phenol; dihydrogen peroxide In water at 79.84℃; for 24h;
	With formic acid; dihydrogen peroxide; potassium carbonate; triethylamine 1.) CH₂Cl₂, 2.) toluene; Multistep reaction;
	With formic acid; dihydrogen peroxide; potassium carbonate; sodium sulfate; triethylamine 1.) CH₂Cl₂, reflux, 3 h 45 min; cooling to room temp., 10 h, 2.) toluene, 1 h; Yield given. Multistep reaction;
	With dihydrogen peroxide; sodium sulfate; triethylamine 1.) 1,2-dichloroethane, reflux, 10 h, 2.) 1,2-dichloroethane, 40 deg C, 2 h; Yield given. Multistep reaction;
	With formic acid; dihydrogen peroxide at 25℃; for 1h;

Reference： [1]Location in patent: experimental part Poskonin [Chemistry of Heterocyclic Compounds, 2009, vol. 45, # 10, p. 1177 - 1183]
[2]Current Patent Assignee: TSINGHUA UNIVERSITY (CHINA) - CN105254599, 2016, A Location in patent: Paragraph 0041; 0042
[3]Kemppainen, Eeva K.; Sahoo, Gokarneswar; Valkonen, Arto; Pihko, Petri M. [Organic Letters, 2012, vol. 14, # 4, p. 1086 - 1089]
[4]Location in patent: experimental part Shi, Yu-Hua; Wang, Zheng; Shi, Ying; Deng, Wei-Ping [Tetrahedron, 2012, vol. 68, # 18, p. 3649 - 3653]
[5]Location in patent: scheme or table Gassama, Abdoulaye; Ernenwein, Cedric; Hoffmann, Norbert [Green Chemistry, 2010, vol. 12, # 5, p. 859 - 865]
[6]Song, Liyan; Yao, Hongliang; Zhu, Liangyu; Tong, Rongbiao [Organic Letters, 2013, vol. 15, # 1, p. 6 - 9]
[7]Kortet, Sami; Claraz, Aurélie; Pihko, Petri M. [Organic Letters, 2020, vol. 22, # 8, p. 3010 - 3013]
[8]De Alvarenga, Elson S.; Carneiro, Vania M. T.; Resende, Gabriela C.; Picanco, Marcelo C.; De Sa Farias, Elizeu; Lopes, Mayara Cristina [Molecules, 2012, vol. 17, # 12, p. 13989 - 14001]
[9]Khotavivattana, Tanatorn; Khamkhenshorngphanuch, Thitiphong; Rassamee, Kitiya; Siripong, Pongpun; Vilaivan, Tirayut [Tetrahedron Letters, 2018, vol. 59, # 27, p. 2711 - 2715]
[10]Choudhary, Hemant; Nishimura, Shun; Ebitani, Kohki [Chemistry Letters, 2012, vol. 41, # 4, p. 409 - 411]
[11]Brimble, Margaret A.; Brimble, Mark T.; Gibson, Jennifer J. [Journal of the Chemical Society. Perkin transactions I, 1989, p. 179 - 184]
[12]Nasman; Pensar [Synthesis, 1985, vol. NO. 8, # 8, p. 786 - 788]
[13]Cao, Ruzhen; Diu, Chong; Liu, Lunzu [Organic Preparations and Procedures International, 1996, vol. 28, # 2, p. 215 - 216]
[14]Li, Xiukai; Ho, Ben; Lim, Diane S. W.; Zhang, Yugen [Green Chemistry, 2017, vol. 19, # 4, p. 914 - 918]

4
[ 4344-84-7 ]
[ 75-05-8 ]
[ 65758-34-1 ]
[ 497-23-4 ]

Reference： [1]Chemische Berichte,1983,vol. 116,p. 375 - 388

5
[ 4344-84-7 ]
[ 75-05-8 ]
[ 65758-34-1 ]
[ 497-23-4 ]
1-acetyl-2H,3H-pyrrol-2-one [ No CAS ]

Reference： [1]Chemische Berichte,1983,vol. 116,p. 375 - 388

6
[ 4344-84-7 ]
[ 20825-71-2 ]
[ 65758-34-1 ]
[ 497-23-4 ]

Reference： [1]Chemische Berichte,1983,vol. 116,p. 375 - 388

7
[ 6117-80-2 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
100%	With 5 wt% Pd nanoparticles loaded on phosphate anion exchanged [Mg₆Al₂(OH)₁₆]CO₃*xH₂O; air at 50℃; for 6h; Irradiation;
78%	With Celite; silver carbonate In benzene for 2h; Heating;
77%	With allyl methyl carbonate In toluene for 6h; Heating;

50%	at 30℃; for 24h; Nocardia corallina B-276;
	With sodium hydrogencarbonate; sodium carbonate at 20℃; for 3h; anodic oxidation on PbO₂;

Reference： [1]Tana, Tana; Guo, Xiao-Wei; Xiao, Qi; Huang, Yiming; Sarina, Sarina; Christopher, Phillip; Jia, Jianfeng; Wu, Haishun; Zhu, Huaiyong [Chemical Communications, 2016, vol. 52, # 77, p. 11567 - 11570]
[2]Chakraborty, T.K.; Chandrasekaran, S. [Tetrahedron Letters, 1984, vol. 25, # 27, p. 2891 - 2894]
[3]Minami, Ichiro; Tsuji, Jiro [Tetrahedron, 1987, vol. 43, # 17, p. 3903 - 3916]
[4]Luna, Hector; Prasad, Kapa; Repic, Oljan [Tetrahedron Asymmetry, 1994, vol. 5, # 3, p. 303 - 306]
[5]Cyr, A.; Wermeckes, B.; Beck, F. [Journal fur Praktische Chemie - Chemiker-Zeitung, 1994, vol. 336, # 7, p. 602 - 607]

8
[ 56579-86-3 ]
[ 497-23-4 ]
[ 59311-29-4 ]

Yield	Reaction Conditions	Operation in experiment
89%	Stage #1: 2-(3,4-methylenedioxyphenyl)-1,3-dithiane With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1h; Stage #2: 2-buten-4-olide In tetrahydrofuran; hexane at -78℃; for 2h;
80%	Stage #1: 2-(3,4-methylenedioxyphenyl)-1,3-dithiane With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1h; Stage #2: 2-buten-4-olide In tetrahydrofuran; hexane at -78℃; for 2h;
80%	Stage #1: 2-(3,4-methylenedioxyphenyl)-1,3-dithiane With n-butyllithium In tetrahydrofuran at -78℃; for 1h; Stage #2: 2-buten-4-olide In tetrahydrofuran at -78℃; for 2h; Stage #3: With acetic acid at -78 - 20℃;	2 Example 2 Preparation of Compound 3 4.00 g of compound 2 was added30mL anhydrous tetrahydrofuran stirring to dissolve,The system was dropped to -78 ,After the dropwise addition of 6.96 mL of butyllithium,The reaction was continued for 1 hour.To the solution was added dropwise 1.44 g of 2 (5H) -furanone and 12 mLOf tetrahydrofuran,The reaction was continued for 2 hours.After 12 mL of acetic acid was added dropwise,The reaction was allowed to proceed to room temperature for 3 hours.The tetrahydrofuran was removed by rotary evaporation,Dichloromethane extraction,Saturated salt water washing,Dried over anhydrous sodium sulfate,The solvent was removed by spin-TooBrownyellowColor oil,Recrystallization from ethyl acetate gave a white solidThe yield was 80%

	With n-butyllithium 1.) THF, hexane, -78 deg C, 30 min, 2.) -78 deg C, 3 h; Multistep reaction;
	With n-butyllithium 1.) THF, hexane, -78 deg C, 0.5 h, 2.) THF, hexane, -78 deg C, 2.5 h; Multistep reaction;

Reference： [1]Boluda, Carlos J.; Lopez, Hermelo; Perez, Jose A.; Trujilloa, Juan M. [Chemical and Pharmaceutical Bulletin, 2005, vol. 53, # 8, p. 930 - 933]
[2]Li, Zhongzhou; Su, Hui; Yu, Weiwei; Li, Xinjun; Cheng, Hao; Liu, Mingyao; Pang, Xiufeng; Zou, Xinzhuo [Organic and Biomolecular Chemistry, 2015, vol. 14, # 1, p. 277 - 287]
[3]Current Patent Assignee: EAST CHINA NORMAL UNIVERSITY - CN104844614, 2016, B Location in patent: Paragraph 0036; 0040; 0041; 0042
[4]Medarde; Pelaez Lamamie De Clairac; Tome; Lopez; San Feliciano [Archiv der Pharmazie, 1994, vol. 327, # 2, p. 91 - 94]
[5]Eich, Eckart; Pertz, Heinz; Kaloga, Macki; Schulz, Jutta; Fesen, Mark R.; Mazumder, Abhijit; Pommier, Yves [Journal of Medicinal Chemistry, 1996, vol. 39, # 1, p. 86 - 95]

9
[ 201230-82-2 ]
(Z)-3-iodoprop-2-en-1-ol [ No CAS ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
76%	With potassium carbonate; hydrazine In tetrahydrofuran at 25℃; for 72h;

Reference： [1]Cowell,A.; Stille,J.K. [Journal of the American Chemical Society, 1980, vol. 102, p. 4193]

10
[ 75-77-4 ]
[ 497-23-4 ]
[ 61550-02-5 ]

Yield	Reaction Conditions	Operation in experiment
88%	With triethylamine In dichloromethane at 0 - 20℃; Inert atmosphere;	(furan-2-yloxy)trimethylsilane (2) To a solution of 2(5H)-furanone (16.9 mL, 238 mmol, 1.0 eq.) in DCM (170 mL, 1.4 M) at 0 °Cwas added triethylamine (33.7 mL, 285 mmol, 1.2 eq.). Then chlorotrimethylsilane (37.4 mL, 250 mmol, 1.05 eq.) was added dropwise to the resulting red brown solution at the same temperature. The suspension was stirred overnight at room temperature. The reaction was diluted with 100 mL pentane and filtered through a frit funnel into a second flask containing 100 mL pentane. The solution was filtered again then concentrated under reduced pressure to give a red brown oil. (If precipitation formed during concentration, immediately dilute it with pentane and filter the solution again.) The crude product was distilled under vacuum (ca. 100 mbar, 105 °C oil bath) to furnish 2 (32.6 g) as a colorless oil in 88% yield.
82%	With triethylamine for 24h; Ambient temperature;
58%	With triethylamine at 20℃; for 20h;

58%	With triethylamine at 0℃; Inert atmosphere;	4.3. Procedure for the synthesis of TMSOF 2¹⁵ A 1-L three-necked flask, equipped with a reflux condenser and a dropping funnel, was charged with furfural (48 g, 0.5 mol), CH2Cl2 (250 mL), formic acid (46 g, 1.0 mol), Na2SO4 (50 g), and K2CO3 (17.5 g). The mixture was vigorously stirred and 30% H2O2 (38 mL) was added in one portion. Vigorous stirring was continued for 30-45 min after which refluxed gently. Then 30% H2O2 (63 mL) was added dropwise with continued stirring. The mixture was stirred overnight after cooling to room temperature. The organic phase was separated, and the aqueous layer was extracted with 50 mL CH2Cl2. The combined organic phase was concentrated in vacuo. 100 mL toluene was added and formic acid was removed by azeotropic distillation. Another 100 mL toluene was added to the reisdue, followed by 1.3 mL triethylamine, and the mixture was allowed to stand for 1 h. After toluene was evaporated, the residual liquid was distilled in vacuo to afford furanone (19.7 g, 47%) as colorless liquid at 63-66 °C/5.9 mmHg.To furanone (19.7 g, 0.142 mol) Et3N (36.0 mL, 0.26 mol) was added, followed by TMSCl (19.7 g, 0.235 mol) at 0 °C under N2. The reaction mixture was filtrated through silica gel, and the cake was washed with dry Et2O to give a clear filtrate. Fractional distillation under reduced pressure of the mixture afforded 2 (13.0 g, 58%) as a yellowish liquid at 76-78 °C/27 mmHg (lit. 44-46 °C/17 mmHg).1H NMR (400 MHz, CDCl3) δ 6.83-6.81 (m, 1H), 6.22-6.20 (m, 1H), 5.11 (d, J=3.1 Hz, 1H), 0.30 (s, 9H).
38%	With triethylamine for 16h; Ambient temperature;
36%	With triethylamine In diethyl ether at -15 - 20℃; for 20h;
	With triethylamine; zinc(II) chloride 1.) Et₂O, THF, 2.) 65 deg C;
	With triethylamine In tetrahydrofuran at 0℃; Reflux;

Reference： [1]Li, Liubo; El Khoury, Anton; Clement, Brennan O.; Harran, Patrick G. [Tetrahedron Letters, 2021, vol. 72]
[2]Pelter; Ward; Sirit [Tetrahedron Asymmetry, 1994, vol. 5, # 9, p. 1745 - 1762]
[3]Hjelmgaard, Thomas; Persson, Tobias; Rasmussen, Thomas B.; Givskov, Michael; Nielsen, John [Bioorganic and Medicinal Chemistry, 2003, vol. 11, # 15, p. 3261 - 3271]
[4]Location in patent: experimental part Shi, Yu-Hua; Wang, Zheng; Shi, Ying; Deng, Wei-Ping [Tetrahedron, 2012, vol. 68, # 18, p. 3649 - 3653]
[5]Brimble, Margaret A.; Brimble, Mark T.; Gibson, Jennifer J. [Journal of the Chemical Society. Perkin transactions I, 1989, p. 179 - 184]
[6]Von der Ohe; Bruckner [New Journal of Chemistry, 2000, vol. 24, # 9, p. 659 - 669]
[7]Capon, Brian; Kwok, Fu-Chiu [Journal of the American Chemical Society, 1989, vol. 111, # 14, p. 5346 - 5356]
[8]Jahjah, Rabih; Gassama, Abdoulaye; Bulach, Veronique; Suzuki, Chikako; Abe, Manabu; Hoffmann, Norbert; Martinez, Agathe; Nuzillard, Jean-Marc [Chemistry - A European Journal, 2010, vol. 16, # 11, p. 3341 - 3354]

11
[ 1700-31-8 ]
[ 497-23-4 ]
[ 96995-00-5 ]
[ 96995-01-6 ]

Reference： [1]Journal of the Chemical Society. Perkin transactions I,1985,p. 35 - 38
[2]Journal of Agricultural and Food Chemistry,1999,vol. 47,p. 1071 - 1077

12
[ 497-23-4 ]
[ 3282-30-2 ]
[ 100921-72-0 ]

Yield	Reaction Conditions	Operation in experiment
80%	With triethylamine In acetonitrile at 60℃; for 4h;
80%	With triethylamine In acetonitrile at 60℃; for 4h;	A solution of triethylamine (6 mmol, 0.83 ml) in acetonitrile (5 ml) was added drop wise to a solution of 5-hydro-furan-2-one (5 mmol, 0.35 ml) and trimethylacetyl chloride (6 mmol, 0.74 ml) in acetonitrile (20 ml) and stirred at 60° C. for 4 h. The precipitate formed, triethylamine hydrochloride, was filtered off. The filtrate was washed with 10% sodium carbonate, dried over MgSO4, distilled off the acetonitrile and the resulting product distilled under vacuum to yield product 5 (80%).
72%	With triethylamine In acetonitrile for 6h; room temperature - 60 deg C;

64%	With triethylamine In acetonitrile for 19h; Inert atmosphere;
	With triethylamine In acetonitrile at 60℃; for 10h;
	With triethylamine In acetonitrile at 20℃; for 72h;	6b'.A Step A: Furan-2-yl 2,2-dimethylpropanoate A solution of triethylamine (43.5 mE; 0.31 mol) inacetonitrile (11 mE) is added to a solution of 2-(5H)-furanone (22 g; 0.26 mol) and trimethylacetyl chloride (38 g; 0.31 mol) in acetonitrile (50 mE). The reaction mixture is stirred for 3 days at ambient temperature, and then the resulting suspension is filtered and rinsed with methyl tert-butyl ether. The organic phase is washed with saturated aqueous sodium bicarbonate solution and saturated aqueous sodium chloride solution and then dried over magnesium sulphate, filtered and concentrated in vacuo. The resulting oil is distilled in vacuo (15 Ton, fractions collected at 76-78° C.) to obtain the title product. 1H NMR (400 MHz, CDC13, 300 K) ö ppm: 7.05 (dd, 1H), 6.36 (dd, 1H), 5.86 (dd, 1H), 1.34 (s, 9H).

Reference： [1]Dhananjeyan, Mugunthu R.; Milev, Youli P.; Kron, Michael A.; Nair, Muraleedharan G. [Journal of Medicinal Chemistry, 2005, vol. 48, # 8, p. 2822 - 2830]
[2]Current Patent Assignee: MICHIGAN STATE UNIVERSITY; UNIVERSITY OF MICHIGAN - US2005/267307, 2005, A1 Location in patent: Page/Page column 4
[3]Hormi, Osmo E. O.; Naesman, Jan H. [Synthetic Communications, 1986, vol. 16, # 1, p. 69 - 78]
[4]Bemis, Troy A.; La Clair, James J.; Burkart, Michael D. [Chemical Communications, 2021, vol. 57, # 8, p. 1026 - 1029]
[5]Nasman [Synthesis, 1985, vol. NO. 8, # 8, p. 788 - 789]
[6]Current Patent Assignee: LIGAND PHARMACEUTICALS INC; SERVIER MONDE - US2020/253993, 2020, A1 Location in patent: Paragraph 0270; 271

13
[ 497-23-4 ]
[ 20005-42-9 ]
[ 108196-98-1 ]

Reference： [1]Collection of Czechoslovak Chemical Communications,1986,vol. 51,p. 2181 - 2185

14
[ 497-23-4 ]
[ 20005-42-9 ]
[ 108196-98-1 ]
[ 123394-10-5 ]

Reference： [1]Journal of Organic Chemistry USSR (English Translation),1989,vol. 25,p. 159 - 165
Zhurnal Organicheskoi Khimii,1989,vol. 25,p. 175 - 182
[2]Journal of Organic Chemistry USSR (English Translation),1989,vol. 25,p. 159 - 165
Zhurnal Organicheskoi Khimii,1989,vol. 25,p. 175 - 182

15
[ 497-23-4 ]
(3aR,7aR)-2-((E)-3-Chloro-allyl)-1,3-dimethyl-octahydro-benzo[1,3,2]diazaphosphole 2-oxide [ No CAS ]
(1R,5S,6R)-6-[(E)-2-((3aR,7aR)-1,3-Dimethyl-2-oxo-octahydro-2λ⁵-benzo[1,3,2]diazaphosphol-2-yl)-vinyl]-3-oxa-bicyclo[3.1.0]hexan-2-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
88%	With n-butyllithium In tetrahydrofuran at -78℃;
	With n-butyllithium 1.) THF, -78 deg C, 5 min, 2.) THF, -78 deg C, 1 h; Yield given. Multistep reaction;

Reference： [1]Hanessian, Stephen; Andreotti, Daniele; Gomtsyan, Arthur [Journal of the American Chemical Society, 1995, vol. 117, # 41, p. 10393 - 10394]
[2]Hanessian, Stephen; Griffin, Andrew; Devasthale, Pratik V. [Bioorganic and Medicinal Chemistry Letters, 1997, vol. 7, # 24, p. 3119 - 3124]

16
[ 497-23-4 ]
[ 100-44-7 ]
[ 22530-98-9 ]

Reference： [1]Tetrahedron,1996,vol. 52,p. 12313 - 12322

17
[ 69739-34-0 ]
[ 497-23-4 ]
[ 121896-38-6 ]

Yield	Reaction Conditions	Operation in experiment
89%	With triethylamine In dichloromethane at 0 - 20℃; for 5h; Inert atmosphere;
70%	With triethylamine In dichloromethane for 2h; Ambient temperature;
70%	With triethylamine In dichloromethane at 0 - 25℃; Inert atmosphere;

70%	With triethylamine In dichloromethane at 0 - 20℃; Inert atmosphere;
65%	With triethylamine In dichloromethane at 0 - 20℃;	tert-Butyl(furan-2-yloxy)dimethylsilane (8) The title compound was synthesized according to a procedure from Synthesis 1991, 1991, 965. A solution of furan-2(5H)-one (168 mg, 2.0 mmol, 1.0 equiv.) in CH2Cl2 (20 mL) was cooled to 0 °C. NEt3 (0.279 mL, 2.0 mmol, 1.0 equiv.) was added followed by dropwise addition of trimethylsilyltrifluoromethanesulfonate (0.362 mL, 2.0 mmol, 1.0 equiv.). The mixture was stirred at roomtemperature overnight then quenched with H2O. The resulting mixture was extracted with CH2Cl2 (3 x20 mL). The combined organic layers were washed with brine, dried over Na2SO4 then concentratedin vacuo. The crude product was purified by silica gel column chromatography (eluent: hexanes) toprovide the title compound (258 mg, 65 % yield) as a colourless oil.

Reference： [1]Kemppainen, Eeva K.; Sahoo, Gokarneswar; Valkonen, Arto; Pihko, Petri M. [Organic Letters, 2012, vol. 14, # 4, p. 1086 - 1089]
[2]Rassu, Gloria; Zanardi, Franca; Battistini, Lucia; Gaetani, Enrico; Casiraghi, Giovanni [Journal of Medicinal Chemistry, 1997, vol. 40, # 2, p. 168 - 180]
[3]Curti, Claudio; Ranieri, Beatrice; Battistini, Lucia; Rassu, Gloria; Zambrano, Vincenzo; Pelosi, Giorgio; Casiraghi, Giovanni; Zanardi, Franca [Advanced Synthesis and Catalysis, 2010, vol. 352, # 11-12, p. 2011 - 2022]
[4]Curti, Claudio; Battistini, Lucia; Zanardi, Franca; Rassu, Gloria; Zambrano, Vincenzo; Pinna, Luigi; Casiraghi, Giovanni [Journal of Organic Chemistry, 2010, vol. 75, # 24, p. 8681 - 8684]
[5]Khotavivattana, Tanatorn; Khamkhenshorngphanuch, Thitiphong; Rassamee, Kitiya; Siripong, Pongpun; Vilaivan, Tirayut [Tetrahedron Letters, 2018, vol. 59, # 27, p. 2711 - 2715]

18
[ 80522-42-5 ]
[ 497-23-4 ]
[ 171201-21-1 ]

Yield	Reaction Conditions	Operation in experiment
97%	With triethylamine In dichloromethane at 0 - 20℃; for 2.5h; Inert atmosphere;
95%	With N-ethyl-N,N-diisopropylamine In dichloromethane 0 deg C to r.t.;
94%	With triethylamine In dichloromethane at 0 - 20℃; for 5h; Inert atmosphere;

94%	With triethylamine In dichloromethane at 0 - 20℃; for 2h;
92%	With triethylamine In dichloromethane at 0 - 20℃; for 2h;
	With triethylamine
	With triethylamine In dichloromethane
	With triethylamine In dichloromethane at 0 - 20℃; for 18h; Inert atmosphere;
	With triethylamine In dichloromethane at 0 - 20℃; for 1h; Inert atmosphere;

Reference： [1]Kortet, Sami; Claraz, Aurélie; Pihko, Petri M. [Organic Letters, 2020, vol. 22, # 8, p. 3010 - 3013]
[2]Martin, Stephen F.; Bur, Scott K. [Tetrahedron Letters, 1997, vol. 38, # 44, p. 7641 - 7644]
[3]Kemppainen, Eeva K.; Sahoo, Gokarneswar; Valkonen, Arto; Pihko, Petri M. [Organic Letters, 2012, vol. 14, # 4, p. 1086 - 1089]
[4]Manabe, Atsushi; Matsumoto, Ryotaro; Shinada, Tetsuro [Synlett, 2015, vol. 26, # 12, p. 1710 - 1714]
[5]Rosso, Giovanni B.; Pilli, Ronaldo A. [Tetrahedron Letters, 2006, vol. 47, # 2, p. 185 - 188]
[6]Martin, Stephen F.; Barr, Kenneth J.; Smith, Dudley W.; Bur, Scott K. [Journal of the American Chemical Society, 1999, vol. 121, # 30, p. 6990 - 6997]
[7]Boukouvalas, John; Loach, Richard P. [Journal of Organic Chemistry, 2008, vol. 73, # 20, p. 8109 - 8112]
[8]Funakoshi, Yuuta; Miura, Tomoya; Murakami, Masahiro [Organic Letters, 2016, vol. 18, # 24, p. 6284 - 6287]
[9]Neumeyer, Markus; Brückner, Reinhard [European Journal of Organic Chemistry, 2017, vol. 2017, # 17, p. 2512 - 2539]

19
[ 497-23-4 ]
[ 100-52-7 ]
[ 81112-82-5 ]

Yield	Reaction Conditions	Operation in experiment
88%	Stage #1: 2-buten-4-olide; benzaldehyde With aluminium tris(2,6-diphenylphenoxide) In toluene at -78℃; for 0.333333h; Stage #2: With 2,2,6,6-tetramethylpiperidinyl-lithium In tetrahydrofuran; hexane; toluene at -78℃; for 0.5h;
76%	With lithium diisopropyl amide In tetrahydrofuran at -78℃; for 1h;
	With C₂₈H₂₃F₆N₃O₂ In dichloromethane at 20℃; for 192h; Inert atmosphere;

Stage #1: 2-buten-4-olide; benzaldehyde With N,O-bis-(trimethylsilyl)-acetamide; tetrabutylammomium bromide; sodium 4-methoxyphenolate In tetrahydrofuran at 0℃; for 4h; Inert atmosphere; Schlenk technique; Stage #2: With hydrogenchloride In tetrahydrofuran; water at 0℃; for 0.5h; Inert atmosphere; Schlenk technique;

Reference： [1]Saito, Susumu; Shiozawa, Masahito; Yamamoto, Hisashi [Angewandte Chemie - International Edition, 1999, vol. 38, # 12, p. 1769 - 1771]
[2]Pohmakotr, Manat; Tuchinda, Patoomratana; Premkaisorn, Pornchai; Reutrakul, Vichai [Tetrahedron, 1998, vol. 54, # 37, p. 11297 - 11304]
[3]Location in patent: experimental part Pansare, Sunil V.; Paul, Eldho K. [Organic and Biomolecular Chemistry, 2012, vol. 10, # 10, p. 2119 - 2125]
[4]Claraz, Aurelie; Oudeyer, Sylvain; Levacher, Vincent [Advanced Synthesis and Catalysis, 2013, vol. 355, # 5, p. 841 - 846]

20
[ 1700-31-8 ]
[ 497-23-4 ]
1,2-Bis-benzyloxy-4-(bis-phenylsulfanyl-methyl)-benzene [ No CAS ]
(3S,4S)-3-(3-Benzyloxy-benzyl)-4-[(3,4-bis-benzyloxy-phenyl)-bis-phenylsulfanyl-methyl]-dihydro-furan-2-one [ No CAS ]

Reference： [1]Journal of Agricultural and Food Chemistry,1999,vol. 47,p. 1071 - 1077

21
[ 1700-31-8 ]
[ 497-23-4 ]
1,2-Bis-benzyloxy-3-(bis-phenylsulfanyl-methyl)-benzene [ No CAS ]
(3S,4S)-3-(3-Benzyloxy-benzyl)-4-[(2,3-bis-benzyloxy-phenyl)-bis-phenylsulfanyl-methyl]-dihydro-furan-2-one [ No CAS ]

Reference： [1]Journal of Agricultural and Food Chemistry,1999,vol. 47,p. 1071 - 1077

22
[ 1700-31-8 ]
[ 497-23-4 ]
1,4-Bis-benzyloxy-2-(bis-phenylsulfanyl-methyl)-benzene [ No CAS ]
(3S,4S)-3-(3-Benzyloxy-benzyl)-4-[(2,5-bis-benzyloxy-phenyl)-bis-phenylsulfanyl-methyl]-dihydro-furan-2-one [ No CAS ]

Reference： [1]Journal of Agricultural and Food Chemistry,1999,vol. 47,p. 1071 - 1077

23
[ 497-23-4 ]
[ 110-15-6 ]

Yield	Reaction Conditions	Operation in experiment
61%	With potassium hydroxide; phosphoric acid; dihydrogen peroxide at 20 - 25℃; for 5h;
19.14%	With dihydrogen peroxide; potassium bromide; potassium hydroxide In water at 100℃; for 3h;	16 Embodiment 16 Maleic acid was prepared by catalytic oxidation of 2(5H)-furanone with potassium bromide and potassium hydroxide as catalysts. The preparation method includes the following steps: (0102) 1 mmol of 2(5H)-furanonl, 25 mg of potassium bromide, 25 mg of potassium hydroxide, 4 mL of deionized water were taken and placed in a thick-walled pressure-resistant tube, and 1 mL of a hydrogen peroxide solution was added. Subsequently, a magnetic stirrer was placed in the thick-walled pressure-resistant tube, and then the above solution was placed in an oil bath at a rotation speed of 500 rpm, and the temperature was raised to 100° C. and stayed for 3 h. After the reaction is completed, the thick-wall pressure tube was immediately taken out and cooled to room temperature in the air. The reaction liquid was transferred from the thick-walled pressure tube, and the water was removed by rotary evaporation to obtain a solid matter. Then, acetone was used to extract the product, where the components insoluble in the acetone were potassium hydroxide and potassium bromide. The potassium hydroxide and potassium bromide can be reused after recovery. The acetone-extracted filtrate was further evaporated and crystallized to obtain a maleic acid product. The maleic acid product was then dissolved in deionized water for a component detection. (0103) Experimental Results: (0104) Components of the above filtrate and yields of the components were detected, and the results showed that the main component of the filtrate was succinic acid with a yield of 19.14%. (0105) The filtrate was diluted 20 times, and then measured and analyzed by using Waters 515 HPLC (high performance liquid chromatography). The result showed that the conversion rate of 2(5H)-furanonl in the present embodiment was about 40%

Reference： [1]Ponomarenko; Badovskaya; Latashko [Chemistry of Heterocyclic Compounds, 2002, vol. 38, # 9, p. 1049 - 1051]
[2]Current Patent Assignee: HEFEI ENERGY RESEARCH INSTITUTE - US11235314, 2022, B2 Location in patent: Page/Page column 11

24
[ 497-23-4 ]
[ 5187-82-6 ]
ethyl 2-oxo-3-oxabicyclo[3.1.0]hexane-6-carboxylate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
7%	With caesium carbonate; In N,N-dimethyl-formamide; at 20℃; for 15h;	To a solution of (2-ethoxy-2-oxoethyl)dimethylsulfanium bromide (60 g, 261.85 mmol) and cesium carbonate (101 g, 309.98 mmol) in N,N-dimethylformamide (300 mL) was stirred for 20 min at 20 C. 2,5-dihydrofuran-2-one (20 g, 237.88 mmol) was added and the mixture was stirred for an additional 15 hours at 20 C. The reaction was quenched by water. The resulting solution was extracted with ethyl acetate, dried with anhydrous sodium sulfate. After filtration, the filtrate was concentrated under vacuum. The residue was purified by flash chromatography on silica gel eluting with ethyl acetate/petroleum ether (3/7) to afford ethyl 2-oxo-3-oxabicyclo[3.1.0]hexane-6-carboxylate (3 g, 7%) as a white solid. LCMS (ESI) [M+H]+=171.

Reference： [1]Journal of Medicinal Chemistry,2004,vol. 47,p. 456 - 466
[2]Patent: US2018/282282,2018,A1 .Location in patent: Paragraph 2288; 2289

25
[ 497-23-4 ]
[ 96-48-0 ]

Yield	Reaction Conditions	Operation in experiment
99%	With hydrogen In methanol for 2h; Autoclave;	7 Example 7 Furanone Catalytic Hydrogenation: The 0.6g Pd0.5 / SiO2 catalyst, 6.0g2 (5H) - furanone, 100ml methanol was added to the autoclave, purged with hydrogen and 0.5 hours, warmed to 80 deg.] C, the hydrogen pressurized to 3.5MPa, hydrogen a flow rate of 180ml / min, stirring 800rmp, after 1.5 hours the reaction yield γ- butyrolactone99%.
92.6%	With 0.5% palladium on silica gel; hydrogen In methanol at 80℃; Autoclave;
86.6%	With Ni#NiO; hydrogen In ethanol at 80℃; for 1h; Autoclave;

	With 1,4-dihydronicotinamide adenine dinucleotide; sodium phosphate buffer; Marchantia polymorpha p68 reductase at 35℃; for 4h;
55 %Spectr.	With palladium 10% on activated carbon; hydrogen at 20℃; for 6h;
	With Old Yellow Enzyme 1; NADH In dimethyl sulfoxide at 30℃; for 24h; Enzymatic reaction;

Reference： [1]Current Patent Assignee: TSINGHUA UNIVERSITY (CHINA) - CN105254599, 2016, A Location in patent: Paragraph 0051; 0052
[2]Li, Xiaodan; Lan, Xiaocheng; Wang, Tiefeng [Green Chemistry, 2016, vol. 18, # 3, p. 638 - 642]
[3]Wang, Yunan; Cao, Feng; Lin, Weiwei; Zhao, Fengyu; Zhou, Jun; Li, Song; Qin, Gaowu [Journal of Materials Chemistry A, 2019, vol. 7, # 30, p. 17834 - 17841]
[4]Shimoda, Kei; Kubota, Naoji [Tetrahedron Asymmetry, 2004, vol. 15, # 24, p. 3827 - 3829]
[5]Shiramizu, Mika; Toste, F. Dean [Angewandte Chemie - International Edition, 2013, vol. 52, # 49, p. 12905 - 12909][Angew. Chem., 2013, vol. 125, # 49, p. 13143 - 13147,5]
[6]Turrini, Nikolaus G.; Hall, Mélanie; Faber, Kurt [Advanced Synthesis and Catalysis, 2015, vol. 357, # 8, p. 1861 - 1871]

26
[ 19444-84-9 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
90%	With sulfuric acid; acetic anhydride at 0℃; for 0.25h;
90%	Stage #1: 3-hydroxyoxolan-2-one With sulfuric acid; acetic anhydride at 0℃; for 0.25h; Stage #2: With dmap at 100℃; for 3h;	3-hydroxy butyrolactone (3) (10 mmol, 0.779 ml) and acetic anhydride (10 mmol, 0.95 ml) were mixed in an RB and 2 drops of conc. H2SO4 was added at 0° C. The pale yellow solution became dark yellow. The reaction mixture was stirred for 15 min. DMAP was added to neutralize H2SO4 and heated at 100° C. for 3 h in an oil bath. The reaction mixture was distilled at atm pressure to remove acetic acid and followed by vacuum distillation to yield the desired product, 4 (90% yield). 1H NMR (CDCl3): δ 4.83(m, 2H), 6.06 (m, 1H), 7.56 (m, 1H). 13C NMR (CDCl3): 72.11, 121.00, 153.22, 173.76.

Reference： [1]Dhananjeyan, Mugunthu R.; Milev, Youli P.; Kron, Michael A.; Nair, Muraleedharan G. [Journal of Medicinal Chemistry, 2005, vol. 48, # 8, p. 2822 - 2830]
[2]Current Patent Assignee: MICHIGAN STATE UNIVERSITY; UNIVERSITY OF MICHIGAN - US2005/267307, 2005, A1 Location in patent: Page/Page column 4

27
[ 28557-00-8 ]
[ 497-23-4 ]
(R)-4-phenyl-4,5-dihydrofuran-2(3H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
86%	Stage #1: phenylzinc chloride; 2-buten-4-olide With chloro-trimethyl-silane In tetrahydrofuran at 30℃; for 1h; Stage #2: With hydrogenchloride

Reference： [1]Kina, Asato; Ueyama, Kazuhito; Hayashi, Tamio [Organic Letters, 2005, vol. 7, # 26, p. 5889 - 5892]

28
[ 63104-44-9 ]
[ 497-23-4 ]
dimethyl 1-oxo-3,3a,5,6,7,8a-hexahydro-1H-cyclopenta[f]isobenzofuran-6,6-dicarboxylate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
60%	With tetraethylammonium chloride In N,N-dimethyl-formamide at 80℃; for 5h; slow addition of diyne;

Reference： [1]Varela, Jesus A.; Rubin, Silvia G.; Gonzalez-Rodriguez, Carlos; Castedo, Luis; Saa, Carlos [Journal of the American Chemical Society, 2006, vol. 128, # 29, p. 9262 - 9263]

29
[ 27607-77-8 ]
[ 497-23-4 ]
[ 61550-02-5 ]

Yield	Reaction Conditions	Operation in experiment
83%	With triethylamine In dichloromethane at 0 - 20℃;
80%	With triethylamine In dichloromethane at 0℃; for 0.75h;
	With triethylamine In dichloromethane at -80℃;

Reference： [1]Evans, David A.; Kvaerno, Lisbet; Dunn, Travis B.; Beauchemin, Andre; Raymer, Brian; Mulder, Jason A.; Olhava, Edward J.; Juhl, Martin; Kagechika, Katsuji; Favor, David A. [Journal of the American Chemical Society, 2008, vol. 130, # 48, p. 16295 - 16309]
[2]Boeckman Jr., Robert K.; Pero, Joseph E.; Boehmler, Debra J. [Journal of the American Chemical Society, 2006, vol. 128, # 34, p. 11032 - 11033]
[3]Garzelli; Samaritani; Malanga [Tetrahedron, 2008, vol. 64, # 19, p. 4183 - 4186]

30
[ 60593-26-2 ]
[ 497-23-4 ]
[ 936021-23-7 ]

Yield	Reaction Conditions	Operation in experiment
80%	With tributylphosphine In dichloromethane; cyclohexane at 20℃;
80%	With tributylphosphine In dichloromethane; cyclohexane at 20℃; for 66h;
80%	With tributylphosphine In dichloromethane; cyclohexane at 20℃; for 24h;	2.16 g of tributylphosphane (0.01 mol) are added drop by drop to a mixture of nitrophosphate (12.58 g, 0.059 mol) and furanone (5 g, 0.059 mol) in 70 ml of cyclohexane. Methylene chloride (7 ml) is added to fully solubilize the reaction mixture, which is agitated for 24 h at ambient temperature. The solvent is evaporated tinder reduced pressure. The crude product is purified by flash chromatography on silica gel with the eluent being a mixture of Et20/pentane (9/1). The nitrofuranone, in diastereoisomeric mixture (55/45), is obtained in the form of a pale yellow oil (14.01 g, 0.047 mol) with a yield of 80%.dP (121.49 MHz; CDCl3; H3PO4) 13.70 (55%), 13.79 (45%).Remark: the 2 diastereoisomers have signals which are superposed or nonattributable in NMR 1H.dH [see original] multiplicity of the carbons d (in ppm) of d (in ppm) form of the signal the diastereoisomer of of the diastereoisomer of (attribution)d31P = 13.70 ppmd31P = 13.70 ppm 2 × 1C, s, (CO) 174.48 174.632 × 1C, d, CIVNO2 90.09 (JCP = 147.1)90.42 (JCP = 148.2)2 × 2C, d, CH2OC(O)68.27 (JCP = 2.8)68.14 (JCP = 9.3)2 × 1C, d, 2CH2OP64.80 (JCP = 7.7)65.05 (JCP = 7.2)2 × 1C, d, CHCIV 40.20 39.752 × 1C, s, CH2CO29.85 (JCP = 7.7)30.19 (JCP = 3.3)2 × 1C, d, CH3CIV 16.37 (JCP = 9.4)16.36 (JCP = 7.7)2 × 2C, d, CH3CH2O16.25 (JCP = 5.2)16.28 (JCP = 5.2) Elemental analysis for C10H18NO7P (molecular weight=295.23):Calculated: C, 40.68; H, 6.15; N, 4.74%.Found: C, 40.67; H, 6.07; N, 4.61%.

Reference： [1]Hardy, Micael; Chalier, Florence; Ouari, Olivier; Finet, Jean-Pierre; Rockenbauer, Antal; Kalyanaraman, Balaraman; Tordo, Paul [Chemical Communications, 2007, # 10, p. 1083 - 1085]
[2]Chalier, Florence; Hardy, Micael; Ouari, Olivier; Rockenbauer, Antal; Tordo, Paul [Journal of Organic Chemistry, 2007, vol. 72, # 21, p. 7886 - 7892]
[3]Current Patent Assignee: CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE; AIX-MARSEILLE UNIVERSITY - US2008/9636, 2008, A1 Location in patent: Page/Page column 5

31
[ 201230-82-2 ]
[ 74-86-2 ]
[ 96-48-0 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
1: 22% 2: 52%	With water; triethylamine In 1,4-dioxane at 20 - 120℃; for 2h;	1 Example 1 The initial charge was 672 mg (2.6 mmol) of Rh(CO)2acac, 2.25 g (22.3 mmol) of triethylamine and 32.8 g (1.8 mol) of water in 400 ml of dioxane. 8.2 l (0.31 mol) of acetylene were injected at room temperature with stirring to a pressure of 3.6 bar. The pressure was then raised to 200 bar with carbon monoxide. The reaction batch was heated to 120° C., raising the pressure to 248 bar, and subsequently stirred for 2 h. After cooling and reactor decompression, the effluent was worked up by distillation. Based on the amount of acetylene used, 52% of 2(5H)-furanone and 22% of butyrolactone had formed. The bottom product of the distillation, which contained the catalyst, was introduced as an initial charge in 400 ml of dioxane and admixed with 2.25 g (22.3 mmol) of triethylamine and 32.8 g (1.8 mol) of water. 8.2 l (0.31 mol) of acetylene were injected at room temperature to a pressure of 3.6 bar. The pressure was then raised to 200 bar with carbon monoxide. The reaction batch was heated to 120° C., raising the pressure to 248 bar, and subsequently stirred for 2 h. After cooling and reactor decompression, the reactor's effluent was worked up by distillation and the bottom product of the distillation, which contained the catalyst, reused. Altogether this procedure was repeated three times without addition of fresh catalyst. The respective yields of product of value (reported as the sum total of 2(5H)-furanone and butyrolactone) are shown in Table 1.
	With water; triethylamine In 1,4-dioxane at 20 - 120℃; for 2h;	1 Example 1 The initial charge was 672 mg (2.6 mmol) of Rh(CO)2acac, 2.25 g (22.3 mmol) of triethylamine and 32.8 g (1.8 mol) of water in 400 ml of dioxane. 8.2 l (0.31 mol) of acetylene were injected at room temperature with stirring to a pressure of 3.6 bar. The pressure was then raised to 200 bar with carbon monoxide. The reaction batch was heated to 120° C., raising the pressure to 248 bar, and subsequently stirred for 2 h. After cooling and reactor decompression, the effluent was worked up by distillation. Based on the amount of acetylene used, 52% of 2(5H)-furanone and 22% of butyrolactone had formed. The bottom product of the distillation, which contained the catalyst, was introduced as an initial charge in 400 ml of dioxane and admixed with 2.25 g (22.3 mmol) of triethylamine and 32.8 g (1.8 mol) of water. 8.2 l (0.31 mol) of acetylene were injected at room temperature to a pressure of 3.6 bar. The pressure was then raised to 200 bar with carbon monoxide. The reaction batch was heated to 120° C., raising the pressure to 248 bar, and subsequently stirred for 2 h. After cooling and reactor decompression, the reactor's effluent was worked up by distillation and the bottom product of the distillation, which contained the catalyst, reused. Altogether this procedure was repeated three times without addition of fresh catalyst. The respective yields of product of value (reported as the sum total of 2(5H)-furanone and butyrolactone) are shown in Table 1.

Reference： [1]Current Patent Assignee: BASF SE - US6346629, 2002, B1 Location in patent: Page column 5
[2]Current Patent Assignee: BASF SE - US6346629, 2002, B1 Location in patent: Page column 5

32
[ 497-23-4 ]
[ 127560-92-3 ]

Yield	Reaction Conditions	Operation in experiment
60%	With benzylamine In methanol at 0℃; for 24h;	(R,S)-3-Benzylamino-1,4-butyrolactone A solution of 2(5H)-furanone (2.5 g, 2.1 ml, 29.7 mmol) in methanol (3 ml) is cooled to 0° C. and treated with benzylamine (3.82 g, 3.9 ml, 35.7 mmol). The resulting solution is stirred at 0° C. for 24 hours. The solvent is evaporated and the residue is purified by flash chromatography (eluent 1/1: EtOAc/hexanes). The fractions comprising the substance with an Rf value of 0.07 are combined and concentrated to give the compound 13 in the form of a yellow oil (3.5 g, 60%). [00121] Elemental analysis for C11H13NO2: Calculated, %: C, 69.09; H, 6.85; N, 7.32. Found, %: C, 68.94; H, 6.82; N, 7.22.

Reference： [1]Current Patent Assignee: UNIVERSITY OF BERN; INNOVATIONSAGENTUR GMBH; CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE - US6660769, 2003, B1 Location in patent: Page column 24

33
[ 617-55-0 ]
[ 3068-00-6 ]
[ 52079-23-9 ]
[ 497-23-4 ]
[ 88246-12-2 ]

Yield	Reaction Conditions	Operation in experiment
	With hydrogen; In Dimethyl ether; at 56 - 110℃; under 120012 Torr; for 0.5 - 2h;Product distribution / selectivity;	HYDROGENATION OF DIMETHYL MALATE:; The following conditions were used Hydrogen pressure 0,1, 10 and 30 bar Substrate 0,4 and 1,5 mol% Catalyst CuMn AI203, particle size 90-180 um Samples are taken at regular intervals after the substrate feed is started. Experiment 1: This was performed according to the procedure described above in Materials, Equipment and Activation Procedure. The reaction temperature was 56C, Hydrogen pressure was 10bar, DME pressure was 150bar, substrate concentration in solution was 0.4 mol%, and 10G of catalyst were used. The following results were obtained: Time on DM L DE BT HGB H-THF HGB equiv Selectivity stream area% area% 5 67.5 0.22 15.16 0.14 15.86 0.1 31.02 95.4% 13 58.4 0.09 21.45 0.27 18.29 0.07 39.74 95.5% 20 63.1 0.15 19.8 0.37 15.6 0.07 35.4 95.9% 30 67.8 0.07 18.2 0.58 12.39 0.06 30.59 95.0% 60 76.5 0.04 15 0.48 7.22 0.04 22.22 94.6% DM = dimethyl malate L = 2 (5H)-Furanone DE = 3,4-dihydroxy methyl butyrate ester BT = butanetriol HGB = 3-hydroxy-gammabutyrolactone (produced by in-situ cyclisation of 3,4-dihydroxy methyl butyrate ester) H-THF = hydroxy-THF Notes: HGB EQUIVALENT = area%"HGB"+ area%"Dihydroxy ester" (as hydroxy ester can be cyclise to HGB) SELECTIVITY DEFINED AS (AREA% USEFUL PRODUCTS) / (AREA % OF ALL PRODUCTS) HGB (S) was obtained in 97.9% ee Experiment 2: This was performed according to the procedure described above in Materials, Equipment and Activation Procedure. The reaction temperature was 110C, Hydrogen pressure was 10bar, DME pressure was 150bar, substrate concentration in solution was 1.5 mol%, and 5.9g of catalyst were used. The following results were obtained : Time on DM L DE BT HGB H-THF HGB equiv Selectivity stream area% area% 5 64.1 0.55 18.22 1.6 15.3 33.52 93.4% 15 72.6 0.24 15.38 0.9 10 0.1 25.38 92.6% 30 77.6 0.16 13.3 0.5 7.8 0.1 21.1 94.2% Note: HGB (S) obtained in 98.8% ee Conclusion: These experiments illustrate high selectivity for HGB in the hydrogenation of dimethyl malate EXPERIMENT-MEOH removal and the effect on the conversion of LDMM to HGB Experiment 3: This was performed according to the procedure described above in Materials, Equipment and Activation Procedure. The reaction temperature was 80C, Hydrogen pressure was 10bar, DME pressure was 150bar, substrate concentration in solution was 0.4 mol%, and 87g of catalyst were used. After 2 hours on stream, the product was found to contain 39.8 area% starting material and 51.5 area% HGB-EQUIVALENT (as defined in Example 1). The product was formed with 85.5% selectivity. The collected product from this experiment, after depressurisation and removal of Methanol, was used as the feed for another hydrogenation, under otherwise identical conditions. The following results were obtained. Time on DM area% L DE BT HGB HGB Selectivity stream equiv area% 50 14.7 5.3 15.2 8 47.4 62.6 73.4% 60 18. 8 4.4 14. 8 11.7 45.5 60.3 74.3% 75 21.15 3.7 21.1 11.5 43.2 64. 3 81.5% 90 13. 4 7. 1 5.5 59.1 66.2 76.4% 105 26.7 3.4 17.5 8.7 40.6 58. 1 79.3% 120 25.6 2.3 17.7 9.5 42 59.7 80. 2% Conclusions : When the reaction products from one incomplete hydrogenation are depressurised and Methanol removed by evaporation, then re-hydrogenated the conversion is increased FROM-50% TO-60%, and the selectivity remains approximately constant.

Reference： [1]Patent: WO2005/23737,2005,A1 .Location in patent: Page/Page column 10-12

34
[ 497-23-4 ]
[ 91632-72-3 ]
[ 557788-88-2 ]

Yield	Reaction Conditions	Operation in experiment
49%	With Santonox R; lithium perchlorate In diethyl ether at 20℃; for 48h;	1 EXAMPLE 1 3a,4,5,6,7,8,9,9a-Octahydro-4,9-epoxynaphtho[2,3-c]furan-1(3H)-one To 3.00 g (35.7 mmol) of furan-2(5H)-one were added 0.96 g (1.78 mmol) of 4,4'-thiobis(6-tert-butyl-m-cresol), 6 mL of a solution of 6.54 g (53.5 mmol) of 4,5,6,7-tetrahydroisobenzofuran in dehydrated ether and 3.18 g of lithium perchlorate, and, after argon flushing, the mixture was stirred for 48 hours at room temperature. The reaction mixture was diluted with 100 mL of ether and poured into 100 ml of water, followed by separation of two layers. The aqueous layer was extracted with methylene chloride (10 ml×3). Combined organic layers were dried over anhydrous magnesium sulfate, filtered and solvent was distilled off under reduced pressure. The residue was purified by means of silica gel column chromatography (hexane:ethyl acetate=4:1, then 2:1, and then 1:1) to obtain 3.62 g of title compound (yield 49%). mp. 105-106° C.

Reference： [1]Current Patent Assignee: KYORIN HOLDINGS, INC.; SAGAMI CHEMICAL RESEARCH INSTITUTE - US2005/124658, 2005, A1 Location in patent: Page/Page column 9

35
[ 5244-34-8 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
63%	With pyridine In methanol	1 EXAMPLE 1 Butenolide E6: The hydroxy ester E5 (110 mg. 0.426 mmol) was hydrogenated in methanol (5 mL) and dry pyridine (0.4 mL) using Lindlar catalyst (5% Pd/CaCO3, 30 mg). After the theoretical amount of hydrogen had been consumed, the mixture was diluted with ether and filtered through Celite to remove the catalyst. The organic solution was washed with 5% aqueous HCl, saturated aqueous sodium hicarbonate and dried over anhydrous magnesium sulfate. The volume was reduced to 25 mL and a catalytic amount of p-toluenesulfonic acid was added to carry out the lactonization. After stirring for 7 h at room temperature, the solution was washed with dilute aqueous sodium bicarbonate and dried as above. The solvents were removed under vacuum and chromatography on silica gel (hexanes:ethyl acetate 78:22) gave the butenolide E6 as a colorless oil (61 mg, 63%). IR (neat): 3022, 2921, 1755, 1690, 1600 1445 cm-1. 1 H-NMR (CDCl3): d 1.77-1.95 (m, 2H), 2.32 (s, 3H), 2.36 (m, 2H), 5.06 (m, 1H), 6-6.22 (m, 2H), 6.39 (d, J=15.7 Hz, 1H), 7-7.22 (m, 4H), 7.48 (d, J=1.4 Hz, 1H).

Reference： [1]Current Patent Assignee: CHEKTEC; THE JOHNS HOPKINS UNIVERSITY - US5539132, 1996, A

36
[ 332-77-4 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
84%	With hydrogenchloride In water; acetone at 20℃; for 16h;	3 A solution of 1 (13g, 0.1 mol) was added acetone (1000 mL) is formed in solution molar concentration 0.1mol.L-1in the organic solution, was added H2O (10 mL), was added dropwise with vigorous stirring hydrochloric acid (1 mL), addition was completed, stirring was continued for 16 hours at room temperature, and solid sodium bicarbonate was added carefully until neutral, filtered through celite, washed with dichloromethane and the combined filtrate was distilled to remove most of the organic solvent under reduced pressure, water was added, the aqueous layer was extracted with dichloromethane, the organic layers were combined, dried over anhydrous magnesium sulfate, filtered, and the filtrate was distilled at atmospheric pressure to remove the solvent, the remaining liquid column chromatography (dichloro methane / methanol) to give crotonyl-γ- lactone 7 (7.1g, 84%).
	With trimethylsilyl bromide In dichloromethane at 20℃;

Reference： [1]Current Patent Assignee: CHONGQING NORMAL UNIVERSITY - CN104151274, 2017, B Location in patent: Paragraph 0059; 0060; 0061
[2]Garzelli; Samaritani; Malanga [Tetrahedron, 2008, vol. 64, # 19, p. 4183 - 4186]

37
[ 625-38-7 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
92%		General procedure: To a solution of oxalyl bromide (1.07 mL, 7.5 mmol, 1.5 equiv) in CH2Cl2 (10 mL) cooled at -10 C was added dropwise a solution of dimethyl sulfoxide (0.53 mL, 7.5 mmol, 1.5 equiv) in CH2Cl2 (10 mL) under the atmosphere of nitrogen. After 10 min, a solution of 3-alkenoic acid (5 mmol, 1.0 equiv) in CH2Cl2 (10 mL) was added. The mixture was then allowed to warm up to room temperature and stirred for 1 h. Distilled water (20 mL) was added dropwise at 0 C. After stirring for 10 min, NaOH (1.00 g, 25 mmol, 5.0 equiv) or K2CO3 (3.45 g, 25 mmol, 5.0 equiv) was added and stirred for 5 h. The organic layer was separated and successively washed with brine (2 × 30 mL). The combined organic extracts were dried (Na2SO4), filtered, and concentrated in vacuum to afford the corresponding gamma-butenolides.

Reference： [1]Synthetic Communications,2019,vol. 49,p. 3001 - 3007
[2]Helvetica Chimica Acta,2014,vol. 97,p. 137 - 145
[3]Journal of Chemical Research,2010,p. 167 - 169
[4]Journal of Heterocyclic Chemistry,2010,vol. 47,p. 436 - 440
[5]Journal of Heterocyclic Chemistry,2011,vol. 48,p. 695 - 698
[6]Tetrahedron Letters,2010,vol. 51,p. 2480 - 2482

38
[ 497-23-4 ]
[ 98-80-6 ]
(R)-4-phenyl-4,5-dihydrofuran-2(3H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
95%	With chlorobis(ethylene)rhodium(I) dimer; (R,R)-(+)-1,4-dimethyl-2,5-diphenylbicyclo[2.2.2]octa-2,5-diene; potassium hydroxide In methanol; dichloromethane at 20℃; for 1h; Inert atmosphere; optical yield given as %ee; enantioselective reaction;
85%	With chlorobis(ethylene)rhodium(I) dimer; (1R,4R,7R)-N-(tert-butyl)-7-isopropyl-5-methylbicyclo[2.2.2]octa-2,5-diene-2-carboxamide In water; toluene at 100℃; for 16h; Inert atmosphere; enantioselective reaction;
77%	With chlorobis(ethylene)rhodium(I) dimer; (R)-[6,6'-bis(bis(4-(trifluoromethyl)phenyl)phosphino)-2,2',3,3'-tetrahydro-5,5'-bibenzo[b][1,4]dioxine]; potassium hydroxide In water; toluene at 20℃; for 18h; Inert atmosphere; optical yield given as %ee; enantioselective reaction;

77%	With chlorobis(ethylene)rhodium(I) dimer; (R)-[6,6'-bis(bis(4-(trifluoromethyl)phenyl)phosphino)-2,2',3,3'-tetrahydro-5,5'-bibenzo[b][1,4]dioxine]; potassium hydroxide In water; toluene at 20℃; for 18h; Inert atmosphere; optical yield given as %ee; enantioselective reaction;
76%	With heterogeneous Rh-Cl complex with chiral diene ligand with amide moiety immobilized on cross-linked polystyrene In water; toluene at 100℃; for 16h; enantioselective reaction;
39%	Stage #1: phenylboronic acid With chlorobis(ethylene)rhodium(I) dimer; (S)-2-diphenylphosphino-2'-phenylsulfinyl-1,1'-binaphthyl In cyclohexane at 40℃; for 0.333333h; Inert atmosphere; Stage #2: 2-buten-4-olide With potassium carbonate In cyclohexane; water for 3h; enantioselective reaction;	General Procedure for the 1,4-addition of α,β-unsaturated carbonyl compounds with arylboronic acid. General procedure: A flame-dried two-necked flask (10 mL) was charged with ligand(R,Ss)-sulfoxide-MOP L2 (4.2 mg, 7.5 μmol, 1.5 mol%), [Rh(C2H4)2Cl]2 (1.5 mg, 3.8 μmol, 1.5mol% Rh), arylboronic acid 2 (1.0 mmol, 2 equiv), capped with a rubber septum, evacuated andbackfilled with argon (3 cycles), and then added cyclohexane (1.0 mL). After stirring at 40 °C for 20min, α,β-unsaturated carbonyl compound 1 (0.5 mmol) and an degassed aqueous solution of K2CO3(0.1 mL, 2.5 M) was added to the mixture and stirred for the appropriate time (followed by TLCuntil completion). The reaction mixture was directly charged onto a column (silica gel) and flashchromatographed with a mixture of hexane/EtOAc or hexane/Et2O to afford the product 3.

Reference： [1]Luo, Yunfei; Cornell, Andrew J. [Angewandte Chemie - International Edition, 2010, vol. 49, # 15, p. 2750 - 2754]
[2]Yasukawa, Tomohiro; Suzuki, Aya; Miyamura, Hiroyuki; Nishino, Kohei; Kobayashi, Shu [Journal of the American Chemical Society, 2015, vol. 137, # 20, p. 6616 - 6623]
[3]Berhal, Farouk; Esseiva, Olivier; Martin, Charles-Henri; Tone, Hitoshi; Genet, Jean-Pierre; Ayad, Tahar; Ratovelomanana-Vidal, Virginie [Organic Letters, 2011, vol. 13, # 11, p. 2806 - 2809]
[4]Location in patent: scheme or table Berhal, Farouk; Wu, Zi; Genet, Jean-Pierre; Ayad, Tahar; Ratovelomanana-Vidal, Virginie [Journal of Organic Chemistry, 2011, vol. 76, # 15, p. 6320 - 6326]
[5]Kuremoto, Tatsuya; Yasukawa, Tomohiro; Kobayashi, Shū [Advanced Synthesis and Catalysis, 2019, vol. 361, # 16, p. 3698 - 3703]
[6]Hoshi, Takashi; Fujita, Masataka; Matsushima, Shouta; Hagiwara, Hisahiro; Suzuki, Toshio [Chemistry Letters, 2018, vol. 47, # 6, p. 800 - 802]

39
[ 943-88-4 ]
[ 497-23-4 ]
[ 1241389-02-5 ]
5-(1-(4-methoxyphenyl)-3-oxobutyl)furan-2(5H)-one [ No CAS ]
5-(1-(4-methoxyphenyl)-3-oxobutyl)furan-2(5H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
84%	With N-((1R,2R)-2-((S)-2-amino-3-methylbutylamino)-1,2-diphenylethyl)-4-methylbenzenesulfonamide; <i>N</i>-<i>tert</i>-butoxycarbonyl-<i>L</i>-phenylalanine In chloroform at 50℃; for 72h; optical yield given as %ee; enantioselective reaction;

Reference： [1]Huang, Huicai; Yu, Feng; Jin, Zhichao; Li, Wenjun; Wu, Wenbin; Liang, Xinmiao; Ye, Jinxing [Chemical Communications, 2010, vol. 46, # 32, p. 5957 - 5959]

40
[ 5447-02-9 ]
[ 497-23-4 ]
[ 1257063-78-7 ]
5-(3',4'-bis(benzyloxy)benzylidene)furan-2(5H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	Stage #1: 2-buten-4-olide With t-butyldimethylsiyl triflate In dichloromethane Stage #2: 3,4-dibenzyloxybenzaldehyde With N-ethyl-N,N-diisopropylamine In dichloromethane at 20℃; for 1h; Stage #3: With 1,8-diazabicyclo[5.4.0]undec-7-ene In dichloromethane at 20℃; for 1h; optical yield given as %de;
40 % de	Stage #1: 2-buten-4-olide With 1,8-diazabicyclo[5.4.0]undec-7-ene In tetrahydrofuran at 20℃; for 0.5h; Inert atmosphere; Stage #2: 3,4-dibenzyloxybenzaldehyde With t-butyldimethylsiyl triflate In tetrahydrofuran at -10 - 20℃; Inert atmosphere; Overall yield = 19 percent; Overall yield = 137 mg;	5-(38,48-Bis(benzyloxy)benzylidene)furan-2(5UH)n-doenre ni(-3). Nitrogen atmosphere, DBU (0.28 mL, 1.88 mmol) was added dropwise to asolution of 2 (158 mg, 1.88 mmol) in dry THF (16 mL). The mixture wasstirred for 30 min at room temperature. After cooled down to -10 °C tertbutyldimethylsilyltrifluoromethanesulfonate (0.48 mL, 2.07 mmol) and 1(600 mg, 1.88 mmol) were added dropwise and the mixture was stirred1 h at -10 °C, then DBU (0.56 mL, 3.76 mmol) was added dropwise. Thereaction mixture was stirred overnight at room temperature, then solventwas removed under vacuum. Ethyl acetate (20 mL), EtOH (5 mL) andsaturated solution offi sodium bisulffite (5 mL) were added to the cruderesidue and stirred overnight at 40 °C. The phases were separated and theorganic layer was diluted with ethyl acetate (15 mL), treated with 2.9 NHCl (3 × 20 mL), washed with brine (20 mL), dried and concentrated toafford a sticky black oil. The crude product was purified on silica gel(75:25 cyclohexane/ethyl acetate) to affiord the title compound as orange/brown oil (137 mg, 0.36 mmol, 19% yield).1H NMR (300 MHz, CDCl3) Z isomer: < = 7.53 (d, J = 7.0 Hz, 4H),7.49 - 7.24 (m, 9H), 6.92 (d, J = 8.4 Hz, 1H), 6.15 (d, J = 5.3 Hz, 1H),5.91 (s, 1H), 5.22 (s, 2H), 5.20 (s, 2H).1H NMR (300 MHz, CDCl3) E isomer: < = 7.53 (d, J = 7.0 Hz, 4H),7.49 - 7.24 (m, 9H), 6.92 (d, J = 8.4 Hz, 1H), 6.21 (d, J = 5.3 Hz, 1H),5.91 (s, 1H), 5.18 (s, 2H)), 5.14 (s, 2H).

Reference： [1]Location in patent: experimental part Chang, Xiaowei; Peng, Weimin; Yao, Yin-Fang; Koek, Jan [Synthetic Communications, 2010, vol. 40, # 22, p. 3346 - 3352]
[2]Baron, Giovanna; Altomare, Alessandra; Regazzoni, Luca; Fumagalli, Laura; Artasensi, Angelica; Borghi, Elisa; Ottaviano, Emerenziana; Del Bo, Cristian; Riso, Patrizia; Allegrini, Pietro; Petrangolini, Giovanna; Morazzoni, Paolo; Riva, Antonella; Arnoldi, Lolita; Carini, Marina; Aldini, Giancarlo [Biochemical Pharmacology, 2020, vol. 173]

41
[ 497-23-4 ]
[ 76311-89-2 ]

Yield	Reaction Conditions	Operation in experiment
89%	Stage #1: 2-buten-4-olide With bromine In tetrachloromethane for 4h; Inert atmosphere; Reflux; Stage #2: With triethylamine In tetrachloromethane at 0 - 20℃; for 1.16667h; Inert atmosphere;
85%	Stage #1: 2-buten-4-olide With bromine In diethyl ether Reflux; Inert atmosphere; Stage #2: With triethylamine In diethyl ether at 0 - 20℃; Inert atmosphere;
85%	Stage #1: 2-buten-4-olide With bromine In diethyl ether for 4h; Inert atmosphere; Reflux; Stage #2: With triethylamine In diethyl ether at 0℃; for 1h; Inert atmosphere;

82%	Stage #1: 2-buten-4-olide With bromine In benzene at 25℃; for 69h; Inert atmosphere; Stage #2: With pyridine In benzene at 0 - 25℃; for 4h; Inert atmosphere;
82%	Stage #1: 2-buten-4-olide With bromine In benzene at 20℃; for 24h; Inert atmosphere; Stage #2: With pyridine at 0 - 20℃; for 4h; Inert atmosphere;
47.6%	Stage #1: 2-buten-4-olide With bromine In diethyl ether for 4h; Darkness; Reflux; Stage #2: With triethylamine In diethyl ether at 0℃; for 1h;
47.6%	Stage #1: 2-buten-4-olide With bromine In diethyl ether at 0 - 35℃; for 4.41667h; Inert atmosphere; Stage #2: With triethylamine In diethyl ether at -5℃; for 1.5h; Inert atmosphere;	1 Example 1: 3-bromofuran-2[5H]-one (compound 2) synthesis Build experimental apparatus: 100mL three-neck flask, reflux condenser, constant pressure dropping funnel and a thermometer, nitrogenNext, added 3.13g (37.3mmol) -furanone, 40 mL of anhydrous ether, with an ice bath temperature of the system down to 0 ° C, then drops toFunnel was added 2.2mL (43.4mmol) bromine, 10 mL of anhydrous diethyl ether, the solution was slowly added dropwise to the reaction system, 25 minutes dropwisePlus completed. After the dropping reflux (35 ° C or so) reaction 4h. Then the system advocated nitrogen lh, to remove excess liquid bromine and bromideHydrogen, then ice bath temperature of the system drops _5 ° C, was slowly added dropwise 6.2mL (44.5mmol) of triethylamine, and mixtures 5mL etherCombined solution was stirred for 30 minutes. Filtered, the filter cake washed with ether, and the combined organic phase was washed with saturated sodium chloride solution and then evaporatedWashed with distilled water, the organic phase was dried over anhydrous sodium sulfate, and separated by column chromatography to give 2.88 g of a white solid, a yield of 47.6%.
46%	Stage #1: 2-buten-4-olide With bromine In diethyl ether for 4h; Darkness; Reflux; Stage #2: With triethylamine In diethyl ether at 0 - 18℃; for 1.16667h;

Reference： [1]De Oliveira, Marllon Nascimento; Fournier, Jeremy; Arseniyadis, Stellios; Cossy, Janine [Organic Letters, 2017, vol. 19, # 1, p. 14 - 17]
[2]Fournier, Jeremy; Arseniyadis, Stellios; Cossy, Janine [Angewandte Chemie - International Edition, 2012, vol. 51, # 30, p. 7562 - 7566]
[3]Fournier, Jeremy; Lozano, Oscar; Menozzi, Candice; Arseniyadis, Stellios; Cossy, Janine [Angewandte Chemie - International Edition, 2013, vol. 52, # 4, p. 1257 - 1261][Angew. Chem., 2013, vol. 125, # 4]
[4]Beaumier, Francis; Dupuis, Marianne; Spino, Claude; Legault, Claude Y. [Journal of the American Chemical Society, 2012, vol. 134, # 13, p. 5938 - 5953]
[5]Aubert, Sidonie; Katsina, Tania; Arseniyadis, Stellios [Organic Letters, 2019, vol. 21, # 7, p. 2231 - 2235]
[6]Cheng, Yun; Ding, Wen-Hui; Long, Qin; Zhao, Min; Yang, Jun; Li, Xiao-Qiang [Journal of labelled compounds and radiopharmaceuticals, 2015, vol. 58, # 9, p. 355 - 360]
[7]Current Patent Assignee: CHINESE ACADEMY OF SCIENCES - CN104557815, 2016, B Location in patent: Paragraph 0099; 0100; 0101
[8]Location in patent: experimental part Banwell, Martin G.; Jones, Matthew T.; Loong, David T.J.; Lupton, David W.; Pinkerton, David M.; Ray, Jayanta K.; Willis, Anthony C. [Tetrahedron, 2010, vol. 66, # 47, p. 9252 - 9262]

42
[ 93614-80-3 ]
[ 497-23-4 ]
C₁₄H₁₄O₃ [ No CAS ]
C₁₄H₁₄O₃ [ No CAS ]

Reference： [1]Chemistry Letters,2011,vol. 40,p. 518 - 520

43
[ 497-23-4 ]
[ 157430-05-2 ]
[ 158703-12-9 ]

Yield	Reaction Conditions	Operation in experiment
57%	Stage #1: benzo[1,3]dioxol-5-yl-(2-[1,3]dithian-2-yl-4,5-dimethoxyphenyl)methanone With n-butyllithium; diisopropylamine In tetrahydrofuran; hexane at -78℃; for 0.666667h; Inert atmosphere; Stage #2: 2-buten-4-olide In tetrahydrofuran; hexane at -78 - 20℃; for 1h;	[0067] Total Synthesis of Patentifiorin A (3) (Scheme 1 ) . To a solution of veratral (4a) (63.2 mmo.) in methanol (MeOH, 250 mL), a solution of bromine (Br2, 69.5 mmol) was added slowly. The reaction was allowed to stir at room temperature for 6 hr to afford 2- bromo-veratral (13.4 g, 86 %). 2-Bromo-veratra. (50.3 mmol) was then dissolved in 300 mL benzene, to which, 1 , 3-propanedifhiol (50.4 mmol) and p-toluenesulfonic acid (p- TsOH, 2.5 mmol) were added. The reaction mixture was allowed to be stirred at reflux for 10 hr then ambient temperature for 48 hr to yield 5 (15.6 g, 93 %). To a stirred solution of compound 5 (46.6 mmoi) in tetrahydrofuran (THF, 1 50 mL) at -78 °C was added n-butyllithium (n-BuLi) (1 .6 M solution in hexanes, 69.9 mmol) in 1 hr, followed by addition of a solution of piperonal (4b) (55.9 mmol) in THF (30 mL). The reaction was allowed for a further 2 hr and then 3 hr at room temperature to yield 6 (9.5 g, 50 %). Compound 6 (20.7 mmol) in CH2CI2 (200 mL) was added a suspension of activated manganese dioxide (MnO2, 345 mmol) at room temperature. The reaction was allowed for 16 hr, and was then filtered through a plug of celite to afford the oxidative product 7 (8.2 g, 98 %). n-Butyliithium (1 .6M solution in hexanes, 100 mmoi) was added dropwise over 5 min to a cooled (-78 °C) solution of diisopropylamine (100 mmoi) in THF (43 mL) under Argon to make fresh lithium diisopropylamide (LDA) solution. The solution was warmed to ambient temperature over 30 min and 25.7 mL added, dropwise via syringe over 3 min to a cooled (-78 °C) THF solution (80 mL) of the dithiane 7 (14.29 mmoi). After 40 min, 2,5-dihydrofuranone (17.1 mmol) as a solution in THF (10 mL) was added over 1 min. The reaction is warmed to ambient temperature for 1 hr to afford 8 (3.95 g, 57 %). A solution of compound 8 (0.85 mmol), mercury oxide (HgO, 0.71 mmoi) and mercury chloride (HgC , 1 .43 mmol) in 84 % acetonitriie (AcCN) aqueous (25 mL) was heated to reflux for 3 hr to afford 9 (134 mg, 52 %). The ketone 9 (0.34 mmol) and p~ TsOH (0.19 mmol) were heated to reflux in benzene (150 mL) for 18 hr to yield the desired compound diphyllin (10, 108 mg, 83 %). To the solution of D-quinovose (0.61 mmol) in pyridine (5 mL) was added 4-dimethylaminopyridine (DMAP, 0.06 mmol) and acetic anhydride (AC2O, 1 .5 mL) at room temperature, and the mixture was stirred overnight and quenched with MeOH (1 mL) to afford 1 ,2,3,4-tetraacetyl-D-quinovose. Without further separation, the tetraacetate was dissolved in glacial acetic acid (AcOH, 1 mL), and 1 .5 mL hydrobromic acid (HBr) (33% in AcOH) was added to the solution slowly at room temperature. The reaction was allowed for 15 min to afford 11 (215 mg, 97 %). To a solution of TBAB (tetrabutylammonium bromide, 0.95 mmoi) and diphyllin (10, 0.95 mmol) in 15 mL of dichloromethane (CH2C ) was added aqueous 0.1 M sodium hydroxide (NaOH, 20 mL). After stirring for 10 min at 40 °C, compound 11 (0.81 mmol) was then added, and the two-phase reaction was stirred for 6 hr at 40 °C to afford the solid 12. Without further separation, the solid 12 (538 mg) was dissolved in MeOH (10 mL), and potassium carbonate (K2CO3, 1 .0 mmol) was then added. The reaction was allowed for 1 hr to afford patentiflorin A (3) (122 mg).

Reference： [1]Current Patent Assignee: HONG KONG BAPTIST UNIVERSITY - WO2013/19662, 2013, A1 Location in patent: Paragraph 0067

44
[ 373-88-6 ]
[ 497-23-4 ]
[ 586-96-9 ]
2-phenyl-3-(trifluoromethyl)tetrahydrofuro[3,4-d]isoxazol-4(2H)-one [ No CAS ]

Reference： [1]Organic Letters,2013,vol. 15,p. 3166 - 3169

45
[ 497-23-4 ]
[ 491-30-5 ]
(6aR,6bR,9aR,9bS)-6,6a,6b,7-tetrahydrofuro[3',4':3,4]cyclobuta[1,2-c]isoquinoline-5,9(9aH,9bH)-dione [ No CAS ]

Reference： [1]Journal of the American Chemical Society,2013,vol. 135,p. 14948 - 14951
[2]Chemistry - A European Journal,2015,vol. 21,p. 6906 - 6912

46
[ 584-02-1 ]
[ 15667-21-7 ]
[ 497-23-4 ]

Reference： [1]Angewandte Chemie - International Edition,2013,vol. 52,p. 12905 - 12909
Angew. Chem.,2013,vol. 125,p. 13143 - 13147,5

47
[ 497-23-4 ]
[ 666707-72-8 ]
[ 1443036-01-8 ]

Yield	Reaction Conditions	Operation in experiment
53%	Stage #1: 2,6-bis(tert-butyldimethylsilyl)-4H-thiopyran With n-butyllithium In tetrahydrofuran; hexane at 0℃; for 0.5h; Stage #2: 2-buten-4-olide In tetrahydrofuran; hexane at 0 - 20℃; for 0.666667h; regioselective reaction;	4.5. Typical procedure for the reaction of lithium salt 1Li with electrophilic reagent General procedure: To a 0°C cooled solution of 4H-thiopyran 1 (102 mg, 0.31 mmol) in tetrahydrofuran (THF) (2 mL) was added n-BuLi (0.37 mmol), 1.2 equivalent of a 2.5M solution in hexane). The deeply red colored solution was stirred for 0.5 h at 0°C then a solution (53 mg, 0.37 mmol) of MeI in THF (1 mL) was added. The deep red color disappeared at the end of the addition, and the resulting yellow solution was stirred for 10 min. at 0°C and for 0.5 h at room temperature. Water (2 mL) was then added. The solution was extracted three times with diethyl ether (3 × 10 mL) and the organic layers were dried over MgSO4 and evaporated. The residue was purified by silica gel column chromatography or preparative TLC.

Reference： [1]Nocentini, Tiziano; Bouillon, Jean-Philippe; Capperucci, Antonella; Portella, Charles [Journal of Sulfur Chemistry, 2013, vol. 34, # 6, p. 692 - 704]

48
[ 98-01-1 ]
[ 110-15-6 ]
[ 497-23-4 ]
[ 110-16-7 ]

Yield	Reaction Conditions	Operation in experiment
1: 61.5% 2: 8.5% 3: 6.7%	With formic acid; dihydrogen peroxide; sodium sulfate In water; ethyl acetate at 59.84℃; for 3h;	2.2.1. Oxidation of furfural All the furfural oxidation reactions were carried out in a three-necked flask of 50 mL, equipped with a condenser to reduce volatilization loss of the solvent. An oil bath was used to control the reaction temperature. In a typical experiment, 10 mL of solvent, 1.5 mL of distilled water, 4.0 g of furfural, 4.0 g of sodium sulfate and an appropriate amount of acid catalyst were added to the flask and heated to the reaction temperature. When the reaction mixture reached the set temperature, 10 mL of hydrogen peroxide (30%) was added to the reactor dropwise during the first hour while stirring. The reaction mixture was sampled and analyzed by a gas chromatograph (GC) and a high performance liquid chromatograph (HPLC).
1: 41.2% 2: 24.2% 3: 10.4%	With potassium chloride; dihydrogen peroxide; potassium hydroxide In water at 100℃; for 3h;	2.2. Experimental procedure All catalytic oxidation reactions were conducted in a 15 ml thickwalledglass tube. Typically, 1 mmol furfural, 0.5 mmol KBr, 0.5mmol mg KOH, 2 ml distilled water (DIW), and 1 ml H2O2 were addedinto the glass tube. Then the tube was heated in a preheated oil bath withmagnetic stirring. After the specified reaction time elapsed, the tube wasput in flowing water to end the reaction. Finally, the resultant productswere stored in a 4 C refrigerator for further analysis.
1: 38.3% 2: 17.3% 3: 12.8%	With formic acid; dihydrogen peroxide; sodium sulfate In water at 59.84℃; for 3h;	2.2.1. Oxidation of furfural All the furfural oxidation reactions were carried out in a three-necked flask of 50 mL, equipped with a condenser to reduce volatilization loss of the solvent. An oil bath was used to control the reaction temperature. In a typical experiment, 10 mL of solvent, 1.5 mL of distilled water, 4.0 g of furfural, 4.0 g of sodium sulfate and an appropriate amount of acid catalyst were added to the flask and heated to the reaction temperature. When the reaction mixture reached the set temperature, 10 mL of hydrogen peroxide (30%) was added to the reactor dropwise during the first hour while stirring. The reaction mixture was sampled and analyzed by a gas chromatograph (GC) and a high performance liquid chromatograph (HPLC).

1: 37.1% 2: 23.34% 3: 20.59%	With dihydrogen peroxide; potassium hydroxide In water at 100℃; for 3h;	10-11 Embodiment 10 Maleic acid was prepared by catalytic oxidation of furfural with potassium hydroxide as a catalyst. The preparation method includes the following steps: 1 mmol of furfural, 50 mg of potassium hydroxide, 4 mL of deionized water were taken and placed in a thick-walled pressure-resistant tube, and 1 mL of a hydrogen peroxide solution was added. Subsequently, a magnetic stirrer was placed in the thick-walled pressure-resistant tube, and then the above solution was placed in an oil bath at a rotation speed of 500 rpm, and the temperature was raised to 100° C. and kept for 3 h. After the reaction is completed, the thick-wall pressure tube was immediately taken out and cooled to room temperature in the air. The reaction liquid was transferred from the thick-walled pressure tube, and the water was removed by rotary evaporation to obtain a solid matter. Then, acetone was used to extract the product, where the component insoluble in the acetone was potassium hydroxide. The potassium hydroxide can be reused after recovery. The acetone-extracted filtrate was further evaporated and crystallized to obtain a maleic acid product. The maleic acid product was then dissolved in deionized water for a component detection. Experimental Results: Components of the above filtrate and yields of the components were detected. The results showed that the main components of the filtrate were maleic acid, furanone and succinic acid, and the yields were 37.10%, 23.34% and 20.59%, respectively.
1: 12.19% 2: 25.23% 3: 27.67%	With dihydrogen peroxide; potassium nitrate In water at 100℃; for 3h;	9 Embodiment 9 Maleic acid was prepared by catalytic oxidation of furfural with potassium nitrate as a catalyst. The preparation method includes the following steps: 1 mmol of furfural, 25 mg of potassium nitrate, 4 mL of deionized water were taken and placed in a thick-walled pressure-resistant tube, and 1 mL of a hydrogen peroxide solution was added. Subsequently, a magnetic stirrer was placed in the thick-walled pressure-resistant tube, and then the above solution was placed in an oil bath at a rotation speed of 500 rpm, and the temperature was raised to 100° C. and kept for 3 h. After the reaction is completed, the thick-wall pressure tube was immediately taken out and cooled to room temperature in the air. The reaction liquid was transferred from the thick-walled pressure tube, and the water was removed by rotary evaporation to obtain a solid matter. Then, acetone was used to extract the product, where the component insoluble in the acetone was potassium nitrate. The potassium nitrate can be reused after recovery. The acetone-extracted filtrate was further evaporated and crystallized to obtain a maleic acid product. The maleic acid product was then dissolved in deionized water for a component detection. Experimental Results: Components of the above filtrate and yields of the components were detected. The results showed that the main components of the filtrate were maleic acid, furanone and succinic acid, and the yields were 12.19%, 25.23% and 27.67%, respectively.
1: 22.99% 2: 8.36% 3: 3.55%	With potassium chloride; dihydrogen peroxide In water at 100℃; for 3h;	8 Embodiment 8 Maleic acid was prepared by catalytic oxidation of furfural with potassium chloride as a catalyst. The preparation method includes the following steps: 1 mmol of furfural, 25 mg of potassium chloride, 4 mL of deionized water were taken and placed in a thick-walled pressure-resistant tube, and 1 mL of a hydrogen peroxide solution was added. Subsequently, a magnetic stirrer was placed in the thick-walled pressure-resistant tube, and then the above solution was placed in an oil bath at a rotation speed of 500 rpm, and the temperature was raised to 100° C. and kept for 3 h. After the reaction is completed, the thick-wall pressure tube was immediately taken out and cooled to room temperature in the air. The reaction liquid was transferred from the thick-walled pressure tube, and the water was removed by rotary evaporation to obtain a solid matter. Then, acetone was used to extract the product, where the component insoluble in the acetone was potassium chloride. The potassium chloride can be reused after recovery. The acetone-extracted filtrate was further evaporated and crystallized to obtain a maleic acid product. The maleic acid product was then dissolved in deionized water for a component detection. Experimental Results: Components of the above filtrate and yields of the components were detected. The results showed that the filtrate included a main component maleic acid, and some other components including furanone and succinic acid, and the yields were 22.99%, 3.55% and 8.36%, respectively.
	With water; dihydrogen peroxide at 60℃; for 4h;
1: 61.5 %Chromat. 2: 8.5 %Chromat. 3: 6.7 %Chromat.	With formic acid; dihydrogen peroxide; sodium sulfate In water; ethyl acetate at 60℃; for 3h; Overall yield = 76.7 %Chromat.;
1: 39.8 %Chromat. 2: 27.8 %Chromat. 3: 8.1 %Chromat.	With formic acid; dihydrogen peroxide; sodium sulfate In water at 60℃; for 3h; Inert atmosphere; Overall yield = 75.7 %Chromat.;
1: 60.3 %Chromat. 2: 12 %Chromat. 3: 6.3 %Chromat.	With formic acid; dihydrogen peroxide; sodium sulfate In water; 1,2-dichloro-ethane at 60℃; for 3h; Overall yield = 78.6 %Chromat.;

Reference： [1]Li, Xiaodan; Lan, Xiaocheng; Wang, Tiefeng [Catalysis Today, 2016, vol. 276, p. 97 - 104]
[2]Yang, Tao; Li, Wenzhi; Ogunbiyi, Ajibola T. [Molecular catalysis, 2021, vol. 504]
[3]Li, Xiaodan; Lan, Xiaocheng; Wang, Tiefeng [Catalysis Today, 2016, vol. 276, p. 97 - 104]
[4]Current Patent Assignee: HEFEI ENERGY RESEARCH INSTITUTE - US11235314, 2022, B2 Location in patent: Page/Page column 7-8
[5]Current Patent Assignee: HEFEI ENERGY RESEARCH INSTITUTE - US11235314, 2022, B2 Location in patent: Page/Page column 7
[6]Current Patent Assignee: HEFEI ENERGY RESEARCH INSTITUTE - US11235314, 2022, B2 Location in patent: Page/Page column 6-7
[7]Badovskaya; Poskonin; Ponomarenko [Russian Journal of General Chemistry, 2014, vol. 84, # 6, p. 1133 - 1140][Zh. Obshch. Khim., 2014, vol. 84, # 6, p. 952 - 959,8]
[8]Li, Xiaodan; Lan, Xiaocheng; Wang, Tiefeng [Green Chemistry, 2016, vol. 18, # 3, p. 638 - 642]
[9]Li, Xiaodan; Lan, Xiaocheng; Wang, Tiefeng [Green Chemistry, 2016, vol. 18, # 3, p. 638 - 642]
[10]Li, Xiaodan; Lan, Xiaocheng; Wang, Tiefeng [Green Chemistry, 2016, vol. 18, # 3, p. 638 - 642]

49
[ 497-23-4 ]
[ 124-63-0 ]
[ 113232-81-8 ]
[ 1621253-45-9 ]

Yield	Reaction Conditions	Operation in experiment
89%	Stage #1: 5,6-dimethoxy-3-oxo-1,3-dihydroisobenzofuran-1-carbonitrile With lithium hexamethyldisilazane In tetrahydrofuran at -78℃; for 0.5h; Stage #2: 2-buten-4-olide In tetrahydrofuran at -78 - -30℃; Stage #3: methanesulfonyl chloride In tetrahydrofuran for 2h; regioselective reaction;
69%	Stage #1: 5,6-dimethoxy-3-oxo-1,3-dihydroisobenzofuran-1-carbonitrile With lithium hexamethyldisilazane In tetrahydrofuran at -78℃; for 0.5h; Inert atmosphere; Stage #2: 2-buten-4-olide In tetrahydrofuran at -40℃; for 30h; Stage #3: methanesulfonyl chloride In tetrahydrofuran at 25℃; for 12h;	14-1 [Example 14-11 Synthesis of9-hydroxy-6,7-dimethoxy- 1 -oxo- 1 ,3-dihydronaphtho[2,3-cj furan-4-yl methanesulfonate [Scheme A + Scheme Gj 172 mg of the 5 ,6-dimethoxy-3-oxo- 1 ,3-dihydroisobenzofuran- 1 -carbonitrile prepared in Example 1-3 (0.79 mmol) was dissolved in 19.6 mL of tetrahydrofuran (0.04 M) under nitrogen atmosphere and 2.36 mL of 1.0 M lithium bis(trimethylsilyl)amide (2.36 mmol) was added at -78 °C. After carrying out reaction at -78 °C for 30 minutes, temperature was increased to -40 °C. After adding 132 mg2(5H)-furanone (1.57 mmol), reaction was carried out at the same temperature for 30 hours. After adding 62 mg of methanesulfonyl chloride (MsC1) (0.79 mmol), reaction was carried out at 25 °C for 12 hours. After terminating the reaction by adding 16 mL of ammonium chloride aqueous solution, followed by extracting with EtOAc (3 x 6 mL), the organic layer was washed with brine (2 x 4 mL), dried with anhydrous Na2SO4, filtered and then concentrated. The remainder was purified by silica gel column chromatography to obtain 191 mg of the target compound 9-hydroxy-6,7-dimethoxy- 1 -oxo- 1 ,3-dihydronaphtho[2,3-cj furan-4-yl methanesulfonate (0.54 mmol, 69%).1H NMR (400 MHz, CDC13) 7.97 (s, 1H), 6.79 (s, 1H), 5.41 (dd, 2H, J = 14.4, 40.8 Hz), 3.94 (s, 3H), 3.31 (s, 3H), 3.28 (s, 3H).

Reference： [1]Kim, Taejung; Jeong, Kyu Hyuk; Kang, Ki Sung; Nakata, Masaya; Ham, Jungyeob [European Journal of Organic Chemistry, 2017, vol. 2017, # 13, p. 1704 - 1712]
[2]Current Patent Assignee: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY - WO2014/119892, 2014, A1 Location in patent: Paragraph 25; 128; 384; 385; 386; 387; 388

50
[ 24424-99-5 ]
[ 497-23-4 ]
[ 113232-81-8 ]
[ 1621253-09-5 ]

Yield	Reaction Conditions	Operation in experiment
83%	Stage #1: 5,6-dimethoxy-3-oxo-1,3-dihydroisobenzofuran-1-carbonitrile With lithium hexamethyldisilazane In tetrahydrofuran at -78 - -30℃; for 0.166667h; Stage #2: 2-buten-4-olide In tetrahydrofuran at -78 - -30℃; Stage #3: di-<i>tert</i>-butyl dicarbonate In tetrahydrofuran for 2h;
72%	Stage #1: 5,6-dimethoxy-3-oxo-1,3-dihydroisobenzofuran-1-carbonitrile With lithium hexamethyldisilazane In tetrahydrofuran at -78℃; for 0.5h; Inert atmosphere; Stage #2: 2-buten-4-olide In tetrahydrofuran at -40℃; for 30h; Stage #3: di-<i>tert</i>-butyl dicarbonate In tetrahydrofuran at 25℃; for 12h;	1-4 [Example 1-41 Synthesis of t-butyl9-hydroxy-6,7-dimethoxy- 1 -oxo- 1 ,3-dihydronaphtho[2,3-cj furan-4-yl carbonate [Scheme A + Scheme Bj 860 mg of 5 ,6-dimethoxy-3-oxo- 1 ,3-dihydroisobenzofuran- 1 -carbonitrile (3.93 mmol) was dissolved in 98.2 mL of tetrahydrofuran (0.04 M) under nitrogen atmosphere and 11.8 mL of 1.0 M lithium bis(trimethylsilyl)amide (11.8 mmol) was added at -78 °C. After carrying out reaction at -78 °C for 30 minutes, followed by increasing temperature to -40 °C, 661 mg of 2(5H)-furanone (7.86 mmol) was addedreaction was carried out at the same temperature for 30 hours. After adding 858 mgt-butoxycarbonyl carbonate (Boc2O) (3.93 mmol), reaction was carried out at 25 °C12 hours. After terminating the reaction by adding 80 mL of ammonium chloride aqueous, followed by extracting with EtOAc (3 x 30 mL), the organic layer was washed with brine (2 x 20 mL), dried with anhydrous Na2504, filtered and then concentrated. The remainder was purified by silica gel column chromatography to obtain 1.06 g of the target compound t-butyl9-hydroxy-6,7-dimethoxy- 1 -oxo- 1 ,3-dihydronaphtho[2,3-cj furan-4-yl carbonate (2.83 mmol, 72%).1H NMR (400 MHz, CDC13) 8.39 (bs, 1H), 7.53 (s, 1H), 7.13 (s, 1H), 5.35 (s, 2H), 4.04 (s, 3H), 4.03 (s, 3H), 1.59 (s, 3H).

Reference： [1]Kim, Taejung; Jeong, Kyu Hyuk; Kang, Ki Sung; Nakata, Masaya; Ham, Jungyeob [European Journal of Organic Chemistry, 2017, vol. 2017, # 13, p. 1704 - 1712]
[2]Current Patent Assignee: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY - WO2014/119892, 2014, A1 Location in patent: Paragraph 25; 89; 172; 173; 174; 175

51
[ 24424-99-5 ]
[ 1621253-40-4 ]
[ 497-23-4 ]
[ 1621253-41-5 ]

Yield	Reaction Conditions	Operation in experiment
80%	Stage #1: 7-oxo-5,7-dihydro[1,3]dioxolo[4,5-f]isobenzofuran-5-carbonitrile With lithium hexamethyldisilazane In tetrahydrofuran at -78℃; for 0.5h; Stage #2: 2-buten-4-olide In tetrahydrofuran at -78 - -30℃; Stage #3: di-<i>tert</i>-butyl dicarbonate In tetrahydrofuran for 2h;
57%	Stage #1: 7-oxo-5,7-dihydro[1,3]dioxolo[4,5-f]isobenzofuran-5-carbonitrile With lithium hexamethyldisilazane In tetrahydrofuran at -78℃; for 0.5h; Inert atmosphere; Stage #2: 2-buten-4-olide In tetrahydrofuran at -40℃; for 30h; Stage #3: di-<i>tert</i>-butyl dicarbonate In tetrahydrofuran at 25℃; for 12h;	13-4 [Example 13-41 Synthesis of t-butyl9-hydroxy- 1 -oxo- 1 ,3-dthydronaphtho[2,3-dj -1 ,3-dioxol[2,3-cj furan-4-yl carbonate [Scheme A + Scheme Bj 84.6 mg of 7-oxo-5,7-dthydroisobenzofuro[5,6-dj [1 ,3jdioxol-5-carbonitrile (0.417 mmol) was dissolved in 10.4 mL of tetrahydrofuran (0.04 M) under nitrogen atmosphere and 1.25 mL of 1.0 M lithium bis(trimethylsilyl)amide (1.25 mmol) was added at -78 °C. After carrying out reaction at -78 °C for 30 minutes, temperature was increased to -40 °C. After adding 70.1 mg of 2(5H)-furanone (0.834 mmol), reaction was carried out at the same temperature for 30 hours. After adding 91.0 mg of tbutoxycarbonyl carbonate (Boc2O) (0.417 mmol), reaction was carried out at 25 °C for 12 hours. After terminating the reaction by adding 10 mL of ammonium chloride aqueous solution, followed by extracting with EtOAc (3 x 5 mL), the organic layer was washed with brine (2 x 3 mL), dried with anhydrous Na2SO4, filtered and then concentrated. The remainder was purified by silica gel column chromatography to obtain 85.6 mg of the target compound t-butyl9-hydroxy- 1 -oxo- 1 ,3-dthydronaphtho[2,3-dj -1 ,3-dioxol[2,3-cj furan-4-yl carbonate (0.238 mmol, 57%).1H NMR (400 MHz, CDC13) 8.37 (bs, 1H), 7.61 (s, 1H), 7.24 (s, 1H), 6.14 (s, 2H), 5.35 (s, 2H), 1.59 (s, 9H).

Reference： [1]Kim, Taejung; Jeong, Kyu Hyuk; Kang, Ki Sung; Nakata, Masaya; Ham, Jungyeob [European Journal of Organic Chemistry, 2017, vol. 2017, # 13, p. 1704 - 1712]
[2]Current Patent Assignee: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY - WO2014/119892, 2014, A1 Location in patent: Paragraph 25; 89; 362; 363; 364; 365

52
[ 17715-69-4 ]
[ 497-23-4 ]
3-(2,4-dimethoxyphenyl)-2H-furan-5-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
50%	With bis-triphenylphosphine-palladium(II) chloride; sodium carbonate; tri tert-butylphosphoniumtetrafluoroborate; XPhos In dimethyl sulfoxide at 100℃; for 2h; Inert atmosphere;	Representative procedure of the reaction General procedure: A solution of 4-methoxybromobenzene (2.67 mmol)and cyclopent-2-en-1-one (3.2 mmol) in DMSO was stirred at ambient temperaturefor 10 min under nitrogen, and treated with Na2CO3 (8.01mmol) and tri-tert-butylphosphonium tetrafluoroborate (0.53 mmol).The reaction mixture was degassed with nitrogen for 10 min and treated withPd(PPh3)2Cl2 (0.13 mmol) and X-Phos (0.26mol), and stirred at 100 0C for 12 h. The reaction mixture was cooledto ambient temperature, diluted with water, and extracted with AcOEt (3 x 50ml). The combined organic layers were washed with brine, dried over anhydrousNa2SO4, and evaporated. Flash chromatograph on silica gel(AcOEt:cyclohexane 1:3) provided the Heck coupling product as brown solid (340mg, 68%).

Reference： [1]Gowala, Tarak Nath; Pabba, Jagadish [Tetrahedron Letters, 2015, vol. 56, # 14, p. 1801 - 1804]

53
[ 50-00-0 ]
[ 39896-97-4 ]
[ 497-23-4 ]
benzyl benzyl[(5-oxotetrahydrofuran-3-yl)methyl]carbamate [ No CAS ]
[ 81616-15-1 ]

Yield	Reaction Conditions	Operation in experiment
1: 78% 2: 10%	Stage #1: formaldehyd; benzyl-carbamic acid benzyl ester With chloro-trimethyl-silane In dichloromethane at 20℃; for 2h; Inert atmosphere; Stage #2: 2-buten-4-olide With bis(cyclopentadienyl)titanium dichloride; samarium; triethylamine hydrochloride In tetrahydrofuran; dichloromethane at 20℃; for 6h; Inert atmosphere;

Reference： [1]Zheng, Xiao; He, Jiang; Li, Heng-Hui; Wang, Ao; Dai, Xi-Jie; Wang, Ai-E; Huang, Pei-Qiang [Angewandte Chemie - International Edition, 2015, vol. 54, # 46, p. 13739 - 13742]

54
[ 1314538-55-0 ]
[ 497-23-4 ]
4-((tert-butoxycarbonyl)aminomethyl)tetrahydrofuran-2(3H)-one [ No CAS ]

Reference： [1]Advanced Synthesis and Catalysis,2014,vol. 356,p. 2749 - 2755

55
[ 863377-22-4 ]
[ 497-23-4 ]
(R)-4-(3-morpholinophenyl)dihydrofuran-2(3H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
27%	With bis(norbornadiene)rhodium(l)tetrafluoroborate; potassium hydroxide; In 1,4-dioxane; at 100℃; for 1h;Microwave irradiation;	Synthesis of authentic (A)-4-(3-morpholinophenyl)dihydrofuran-2(3A/)-one (Compound XXIV) for comparison with compound (XXIII). A solution of bis(norbornadiene)rhodium (I) tetrafluoroborate (available from Aldrich) (18.70 mg, 0.05 mmol) and <strong>[863377-22-4](3-morpholinophenyl)boronic acid</strong> (1035 mg, 5.00 mmol) in 1,4-dioxane (10 mL) was treated with furan-2(5 /)-one (0.142 mL, 2.0 mmol) and KOH solution (3.8 M, 1.053 mL, 4.00 mmol). The resulting solution was heated to 100°C for 1 h in a microwave reactor. The reaction was allowed to cool and concentrated in vacuo to give a brown oil. The residue was purified by chromatography (50 g KPNH cartridge) eluting with a gradient of 0-50percent EtOAc in' cyclohexane over 45 min. The relevant fractions were concentrated in vacuo to give (R)-4-(3- morpholinophenyl)dihydrofuran-2(3 )-one (compound XXIV) (132 mg, 27percent) as a white solid: LCMS (System C) RT= 0.82 min, 100percent, ES+ve /77/z248 (M+H)+; [-]D22 = -28.3 (c = 1.70 in CHCI3); Chiral HPLC RT= 23.4min, 94percent, RT=25.4 min 6percent on a Chiralpak ID column (25 cm chi 4.6 mm) eluting with 20percent isopropanol-heptane, flow-rate 1 mL/min, detecting at 215 nm.

Reference： [1]Patent: WO2016/46226,2016,A1 .Location in patent: Page/Page column 51-52

56
[ 497-23-4 ]
nitrofuranone [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
60%	With manganese(IV) oxide; 2,2,6,6-Tetramethyl-1-piperidinyloxy free radical; sodium nitrite In tetrahydrofuran at 80℃;	3 Example 3 To the reaction flask was added 3,4-enebutyrolactone (1mmol), sodium nitrite (2mmol), manganese dioxide (5mmol), 2,2,6,6- tetramethyl piperidine N-oxide (0.1mmol) and tetrahydrofuran (3 ml), 80 deg. C reaction; TLC tracked reaction completion; after the reaction, the crude product obtained was purified by column chromatography (petroleum ether: ethyl acetate = 4: 1) to give the desired product (60% yield).

Reference： [1]Current Patent Assignee: ZHANGJIAGANG INSTITUTE OF INDUSTRIAL TECHNOLOGIES SOOCHOW UNIVERSITY - CN105669616, 2016, A Location in patent: Paragraph 0013

57
[ 531-88-4 ]
[ 497-23-4 ]
9-hydroxy-6,7-dimethoxynaphtho[2,3-c]furan-1(3H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
65%		.5,6-dimethoxy-benzofuran-isobutyl -1 (3H) - one 1.0 g (5.15 mmol) under a nitrogen condition tetrahydrofuran 128.8 mL (0.04 M) and then dissolved, at 78oC-lithium bis (trimethylsilyl) amide 1.0 It was added 15.5 mL M (15.5 mmol). After reacting for 30 minutes at -78oC, 2 (5H) - Pew ranon 866 mg (10.3 mmol) added after the reaction for 30 hours at the same temperature and was 5 hours at 25 C by adding. Again after a temperature of 0oC, camphorsulfonic acid and then added to 8.37 g (36.1 mmol), was 12 hours at 65oC. It was added to 100 mL aqueous sodium hydrogen carbonate solution to terminate the reaction and extracted with EtOAc (3 × 30 mL). Washing the organic layer with brine (brine, 10 mL × 2), dried over anhydrous Na2SO4, filtered and concentrated. To yield the title compound the residue was purified by silica gel column chromatography to give 9-hydroxy-6,7-dimethoxy-naphtho [2,3-c] furan -1 (3H) - one to give the 870 mg (3.35 mmol, 65%)

Reference： [1]Patent: KR101492960,2015,B1 .Location in patent: Paragraph 0138-0140

58
[ 497-23-4 ]
[ 139016-01-6 ]
6-(benzyloxy)-9-hydroxy-7-methoxynaphtho[2,3-c]furan-1(3H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
68%	Stage #1: 5-(Benzyloxy)-6-methoxyisobenzofuran-1(3H)-one With lithium hexamethyldisilazane In tetrahydrofuran at -78℃; for 0.5h; Inert atmosphere; Stage #2: 2-buten-4-olide In tetrahydrofuran at -78 - 25℃; for 35h; Inert atmosphere; Stage #3: With camphor-10-sulfonic acid In tetrahydrofuran at 0 - 65℃; for 12h; Inert atmosphere;	1.5 Synthesis of 6-(benzyloxy)-9-hydroxy-7-methoxynaphtho[2,3-c]furan-1(3H)-one 6- (benzyloxy) -5-methoxy-benzofuran-isobutyl -1 (3H) - one 42.9 mg (0.159 mmol) under a nitrogen condition tetrahydrofuran 4.0 mL (0.04 M) and then dissolved, at 78oC-lithium bis ( trimethylsilyl) amide was added 1.0 M 0.48 mL (0.477 mmol). After 30 min at -78oC, 2 (5H) - Pew ranon 26.7 mg (0.318 mmol) added after the reaction for 30 hours at the same temperature and was added to 5 hours at 25 ° C. Again after a temperature of 0oC, camphorsulfonic acid and then added to 259 mg (1.11 mmol), was 12 hours at 65oC. It was added 3 mL of aqueous sodium hydrogen carbonate solution to terminate the reaction and extracted with EtOAc (3 × 2 mL). Washing the organic layer with brine (brine, 2 × 2 mL), dried over anhydrous Na2SO4, filtered and concentrated. Silica gel column chromatography to give the title compound as a residue 6- (benzyloxy) -9-hydroxy-7-methoxy-naphtho [2,3-c] furan -1 (3H) - one 36.3 mg (0.108 mmol, 68%) was obtained.Select words

Reference： [1]Current Patent Assignee: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY - KR101492960, 2015, B1 Location in patent: Paragraph 0108-0110

59
[ 42417-39-0 ]
[ 36603-83-5 ]
[ 50768-69-9 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With oxygen; nitrogen(II) oxide; In water; at 25.0℃; under 760.051 Torr;	As shown in FIG. 3, a desamination reaction (second reaction) of homoserine lactone hydrochloride using water as a solvent was carried out.A portion of the upper layer recovered in the first reaction (80.2 mL)And 120 g of HSL · HCl were placed in a reactor and reacted while injecting NO / Air (O 2) gas at room temperature (25 C.) and atmospheric pressure (1 atm). GC analysis was performed to confirm the presence of unreacted HSL · HCl, and the product was placed in a separating funnel and allowed to stand until it was separated.64.04 g of the bottom layer was recovered from the layered solution and the recovered bottom layer was evaporated under reduced pressure (2-4 torr) to 50 & lt; 0 & gt; C to recover 58.28 g of product. As a result of analyzing the components of the product, Cl-GBL contained 91.34%, HO-GBL contained 5.04%, and furanone contained 2.62%.After separating the lower layer, the upper layer was 154.05 g, and 80 mL (94.25 g) was used as a solvent for the tertiary reaction. The residue (59.8 g) was extracted three times with chloroform (60 mL / 60 mL / 60 mL) and the combined extracts were evaporated under reduced pressure to recover 18.57 g of product. As a result of analyzing the components of the product, 87.36% of Cl-GBL, 4.11% of HO-GBL and 7.37% of furanone were contained.After the chloroform extraction, the solvent was evaporated under reduced pressure to recover 7.8 g of the product. As a result of analyzing the components of the product, Cl-GBL was contained in 2.28%, HO-GBL in 91.44%, and furanone in 0.92%.

Reference： [1]Patent: KR2015/118287,2015,A .Location in patent: Paragraph 0078-0083

60
[ 42417-39-0 ]
[ 36603-83-5 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With ferric nitrate; In water; at 25.0℃; under 760.051 Torr; for 2h;	The reactor was charged with 0.5 g of HSL.HCl and 6.5 g of water as a reactant. An Fe (NO3) 3 catalyst was added to the reactor in the ratio shown in Table 5 below to carry out the deamination reaction of HSL · HCl. The reaction conditions were 25 C and 1 atm. The product was partially recovered and the components were analyzed. The results are shown in Table 5 below.

Reference： [1]Patent: KR2015/118287,2015,A .Location in patent: Paragraph 0095; 0125-0127

61
[ 67-56-1 ]
[ 42417-39-0 ]
[ 96-48-0 ]
[ 36603-83-5 ]
[ 25600-25-3 ]
[ 4508-99-0 ]
4-hydroxy-2-methoxybutanoic acid [ No CAS ]
4-hydroxy-2-chlorobutanoic acid [ No CAS ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With 5 % platinum on carbon; nitrogen(II) oxide; at 80.0℃; under 11400.8 Torr; for 2h;Inert atmosphere;	The reactor was charged with 1 g of HSL · HCl, 40 g of methanol and 0.05 g of Pt (5) / Ac, followed by NO / N2 (15 atm, 1: 1 (v / v) As above, additional H2 (6.5 atm) was added and the desmethylation reaction of HSL.HCl was performed. The product was partially recovered and the components were analyzed. The results are shown in Table 8 below.

Reference： [1]Patent: KR2015/118287,2015,A .Location in patent: Paragraph 0138; 0139-0142

62
[ 67-56-1 ]
[ 42417-39-0 ]
[ 96-48-0 ]
[ 36603-83-5 ]
[ 25600-25-3 ]
[ 4508-99-0 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With 5 % platinum on carbon; nitrogen(II) oxide; at 100.0℃; under 11400.8 Torr; for 2h;Inert atmosphere;	The reactor was charged with 1 g of HSL · HCl, 40 g of methanol and 0.05 g of Pt (5) / Ac, followed by NO / N2 (15 atm, 1: 1 (v / v) As above, additional H2 (6.5 atm) was added and the desmethylation reaction of HSL.HCl was performed. The product was partially recovered and the components were analyzed. The results are shown in Table 8 below.

Reference： [1]Patent: KR2015/118287,2015,A .Location in patent: Paragraph 0138; 0139-0142

63
[ 67-56-1 ]
[ 42417-39-0 ]
[ 36603-83-5 ]
[ 25600-25-3 ]
[ 4508-99-0 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With 5 % platinum on carbon; nitrogen(II) oxide; at 100.0℃; under 11400.8 Torr; for 2h;Inert atmosphere;	The reactor was charged with HSL · HCl, methanol and / or water as described in Table 9 below. The reactor was charged with Pt (5) / Ac and NO / N2 (15 atm, 1: 1 (v / v)). The reaction was carried out at a reaction time and a reaction temperature as shown in Table 9 below. The product was partially recovered and the components were analyzed. The results are shown in Table 9 below.

Reference： [1]Patent: KR2015/118287,2015,A .Location in patent: Paragraph 0138; 0144-0147

64
[ 67-56-1 ]
[ 42417-39-0 ]
[ 36603-83-5 ]
[ 50768-69-9 ]
[ 25600-25-3 ]
4-hydroxy-2-methoxybutanoic acid [ No CAS ]
4-hydroxy-2-chlorobutanoic acid [ No CAS ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With 5 % platinum on carbon; nitrogen(II) oxide; In water; at 100.0℃; under 11400.8 Torr; for 2h;Inert atmosphere;	The reactor was charged with HSL · HCl, methanol and / or water as described in Table 9 below. The reactor was charged with Pt (5) / Ac and NO / N2 (15 atm, 1: 1 (v / v)). The reaction was carried out at a reaction time and a reaction temperature as shown in Table 9 below. The product was partially recovered and the components were analyzed. The results are shown in Table 9 below.

Reference： [1]Patent: KR2015/118287,2015,A .Location in patent: Paragraph 0144-0146

65
[ 67-56-1 ]
[ 42417-39-0 ]
[ 36603-83-5 ]
[ 25600-25-3 ]
4-hydroxy-2-methoxybutanoic acid [ No CAS ]
4-hydroxy-2-chlorobutanoic acid [ No CAS ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With 5 % platinum on carbon; nitrogen(II) oxide; In chloroform; at 100.0℃; under 11400.8 Torr; for 2h;Inert atmosphere;	1 g of HSL · HCl, 20 g of methanol, 20 g of chloroform and 0.1 g of Pt (5) / Ac were added to the reactor. The reaction was carried out in the presence of NO / N2 (15 atm, 1: 1 (v / v)) and the reaction was carried out at a reaction time and a reaction temperature as shown in Table 10. The product was partially recovered and the components were analyzed. The results are shown in Table 10 below.

Reference： [1]Patent: KR2015/118287,2015,A .Location in patent: Paragraph 0138; 0149-0152

66
[ 67-56-1 ]
[ 42417-39-0 ]
[ 36603-83-5 ]
[ 50768-69-9 ]
[ 25600-25-3 ]
4-hydroxy-2-chlorobutanoic acid [ No CAS ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With 5 % platinum on carbon; nitrogen(II) oxide; In water; at 100.0℃; under 11400.8 Torr; for 2h;Inert atmosphere;	The reactor was charged with HSL · HCl, methanol and / or water as described in Table 9 below. The reactor was charged with Pt (5) / Ac and NO / N2 (15 atm, 1: 1 (v / v)). The reaction was carried out at a reaction time and a reaction temperature as shown in Table 9 below. The product was partially recovered and the components were analyzed. The results are shown in Table 9 below.

Reference： [1]Patent: KR2015/118287,2015,A .Location in patent: Paragraph 0144-0146

67
[ 36603-83-5 ]
[ 96-48-0 ]
[ 627-00-9 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With palladium on activated carbon; at 130℃; under 760.051 Torr; for 4h;	3 g of Cl-GBL and the solvent of Table 11 (30 g) and the catalyst were charged into the reactor, respectively, and the reaction was allowed to proceed to evaluate the degree of dechlorination of Cl-GBL. The reaction was allowed to proceed at atmospheric pressure (1 atm), and the product was partially recovered to analyze the components. The results are shown in Table 11 below.

Reference： [1]Patent: KR2015/118287,2015,A .Location in patent: Paragraph 0154-0158

68
[ 36603-83-5 ]
[ 96-48-0 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
	With palladium on activated carbon In diethylene glycol dimethyl ether at 130℃; for 4h; Overall yield = 98.85 %;	6-1 Dechlorination of chloro-gamma butyrolactone 3 g of Cl-GBL and the solvent of Table 11 (30 g) and the catalyst were charged into the reactor, respectively, and the reaction was allowed to proceed to evaluate the degree of dechlorination of Cl-GBL. The reaction was allowed to proceed at atmospheric pressure (1 atm), and the product was partially recovered to analyze the components. The results are shown in Table 11 below.

Reference： [1]Current Patent Assignee: KOREA RESEARCH INSTITUTE OF CHEMICAL TECHNOLOGY; CJ CORPORATION - KR2015/118287, 2015, A Location in patent: Paragraph 0154-0158; 0188

69
[ 50768-69-9 ]
[ 497-23-4 ]
[ 107-02-8 ]

Yield	Reaction Conditions	Operation in experiment
51.4%	at 300℃; for 3h; Inert atmosphere;	9 Dehydration of hydroxy-gamma butyrolactone The hydrolytic dehydration reaction was carried out at the conversion of HO-GBL to GBL using the catalyst (amount of catalyst 2 g) and conditions (feed rate = 0.02 ml / min, reaction pressure = atmospheric pressure)

Reference： [1]Current Patent Assignee: KOREA RESEARCH INSTITUTE OF CHEMICAL TECHNOLOGY; CJ CORPORATION - KR2015/118287, 2015, A Location in patent: Paragraph 0258-0261

70
[ 872-85-5 ]
[ 497-23-4 ]
3,5,5-tris(hydroxy(pyridin-4-yl)methyl)furan-2(5H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
87%	With diethylamine In diethyl ether for 0.5h; Inert atmosphere; regioselective reaction;	4 General procedure: A solution (0.05mol-%) of the appropriate furan-2-one (1 eq.) in dry diethyl ether (DEE) was mixed with the N-heterocyclic carbaldehyde (1, 2 or 3 eq.) under a nitrogen atmosphere at 0°C. After stirring for 30min, excess dry diethylamine (4 eq.) was added dropwise. Stirring was continued for 30min. The solution was allowed to warm up over night and the product usually precipitated as fluffy powder. The precipitate was washed with cold DEE and dried in vacuo.

Reference： [1]Uhrner, Fabian; Lederle, Felix; Namyslo, Jan C.; Gjikaj, Mimoza; Schmidt, Andreas; Hübner, Eike G. [Tetrahedron, 2017, vol. 73, # 30, p. 4472 - 4480]

71
[ 39021-62-0 ]
[ 497-23-4 ]
5-(hydroxy(N-methylimidazol-5-yl)methyl)furan-2(5H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
49%	With diethylamine; In diethyl ether; for 0.5h;Inert atmosphere;	General procedure: A solution (0.05mol-%) of the appropriate furan-2-one (1 eq.) in dry diethyl ether (DEE) was mixed with the N-heterocyclic carbaldehyde (1, 2 or 3 eq.) under a nitrogen atmosphere at 0C. After stirring for 30min, excess dry diethylamine (4 eq.) was added dropwise. Stirring was continued for 30min. The solution was allowed to warm up over night and the product usually precipitated as fluffy powder. The precipitate was washed with cold DEE and dried in vacuo.

Reference： [1]Tetrahedron,2017,vol. 73,p. 4472 - 4480

72
[ 50-00-0 ]
[ 497-23-4 ]
[ 109765-92-6 ]

Yield	Reaction Conditions	Operation in experiment
36%	With 1,4-diaza-bicyclo[2.2.2]octane; tetrabutylammomium bromide In 1,4-dioxane; water at 20℃; for 72h;	13 At room temperature, the substrate crotonyl-γ- lactone 7 (8.4g, 0.1 mol) was added dioxane (250 mL) is formed in solution molar concentration 0.4 mol.L-1in the organic solution, was added water (250 mL ), were successively added 1,4-diazabicyclo [2.2.2]octane (1.12 g, 10 mmol), tetra-n-butylammonium bromide (3.22g, 10 mmol), aqueous formaldehyde (40%, 30 mL), brought to room temperature stirred for three days sealing, spin remove most of the organic solvent under reduced pressure, the aqueous layer was extracted with DCM and the combined extracts were dried over anhydrous MgSO4, filtered, concentrated and column chromatography (dichloromethane / methanol) to give α- hydroxymethyl -γ- crotonyl-lactone 8 (4.1g, 36%).

Reference： [1]Current Patent Assignee: CHONGQING NORMAL UNIVERSITY - CN104151274, 2017, B Location in patent: Paragraph 0099; 0100; 0101

73
[ 20295-21-0 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
82%	With sulfuric acid In water; acetone at 20℃; for 12h;	8 At room temperature, H2O (10 mL) was added 2 (31.6 g, 0.2 mol) in acetone (1000 mL) solution, with vigorous stirring was added dropwise sulfuric acid (1 mL), addition was completed, stirring was continued for 12 hours at room temperature, carefully added solid carbonate sodium hydrogen to neutral, filtered through celite, washed with dichloromethane and the combined filtrate was distilled to remove most of the organic solvent under reduced pressure, water was added, the aqueous layer was extracted with dichloromethane, the organic layers were combined, dried over anhydrous magnesium sulfate, filtered, filtrate solvent atmospheric distillation, the remaining liquid column chromatography (dichloromethane / methanol) to give crotonyl- γ- lactone 7 (14 g, 82%).

Reference： [1]Current Patent Assignee: CHONGQING NORMAL UNIVERSITY - CN104151274, 2017, B Location in patent: Paragraph 0079; 0080; 0081

74
[ 20295-23-2 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
79%	With phosphoric acid In water; acetone at 20℃; for 12h;	9 At room temperature, H2O (10 mL) was added to a solution of 3 (42.9 g, 0.2 mol) in acetone (1000 mL). Phosphoric acid (1 mL) was added dropwise with vigorous stirring. After stirring, the mixture was stirred at room temperature for 12 hours. Carefully add the solid sodium bicarbonate neutral and neutral, diatomaceous earth filter, dichloromethane washing, combined filtrate, vacuum distillation to remove most of the organic solvent, add water, water extraction with methylene chloride, combined organic layer, anhydrous Dried over magnesium sulfate, filtered, and the solvent was removed by distillation at atmospheric pressure. The remaining liquid column chromatography (dichloromethane / methanol) gave l-carnitolide 7 (13.3g, 79%).

Reference： [1]Current Patent Assignee: CHONGQING NORMAL UNIVERSITY - CN104151274, 2017, B Location in patent: Paragraph 0083; 0084; 0085

75
[ 20295-22-1 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
81%	With nitric acid In water; acetone at 20℃; for 12h;	10 At room temperature, H2O (10 mL) was added to a solution of 4 (37.3 g, 0.2 mol) in acetone (1000 mL) and nitric acid (1 mL) was added dropwise with vigorous stirring. After stirring, the mixture was stirred at room temperature for 12 hours. Carefully add solid sodium bicarbonate and neutral to earth, diatomite filter, dichloromethane washing, combined filtrate, vacuum distillation to remove most of the organic solvent, add water, water extraction with methylene chloride, combined organic layer, anhydrous Dried over magnesium sulfate, filtered, and the solvent was removed by distillation at atmospheric pressure. The remaining liquid column chromatography (dichloromethane / methanol) gave l-carnitolide 7 (13.6g, 81%).

Reference： [1]Current Patent Assignee: CHONGQING NORMAL UNIVERSITY - CN104151274, 2017, B Location in patent: Paragraph 0087; 0088; 0089

76
2,5-bis(2-hydroxyethoxy)-2,5-dihydrofuran [ No CAS ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
73%	With acetic acid In water; acetone at 20℃; for 12h;	11 At room temperature, H2O (10 mL) was added to a solution of 5 (38.1 g, 0.2 mol) in acetone (1000 mL) and acetic acid (1 mL) was added dropwise with vigorous stirring. After completion of the addition, stirring was continued at room temperature for 12 hours, Carefully add solid sodium bicarbonate and neutral to earth, diatomite filter, dichloromethane washing, combined filtrate, vacuum distillation to remove most of the organic solvent, add water, water extraction with methylene chloride, combined organic layer, anhydrous Dried over magnesium sulfate, filtered, and the solvent was removed by distillation at atmospheric pressure. The remaining liquid column chromatography (dichloromethane / methanol) gave l-carnitolide 7 (12.38, 73%).

Reference： [1]Current Patent Assignee: CHONGQING NORMAL UNIVERSITY - CN104151274, 2017, B Location in patent: Paragraph 0091; 0092; 0093

77
[ 7093-88-1 ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
86%	With hydrogenchloride In water; acetone at 20℃; for 12h;	12 At room temperature, H2O (10 mL) was added 6 (37.2 g, 0.2 mol) in acetone (1000 mL) solution was added dropwise with vigorous stirring acid (1 mL), addition was completed, stirring was continued for 12 hours at room temperature, carefully added solid sodium bicarbonate to neutral, filtered through celite, washed with dichloromethane and the combined filtrate was distilled to remove most of the organic solvent under reduced pressure, water was added, the aqueous layer was extracted with dichloromethane, the organic layers were combined, dried over anhydrous magnesium sulfate , filtered, and the filtrate solvent was distilled at atmospheric pressure, the remaining liquid column chromatography (dichloromethane / methanol) to give crotonyl-γ-lactone 7 (14.5 g, 86%) .

Reference： [1]Current Patent Assignee: CHONGQING NORMAL UNIVERSITY - CN104151274, 2017, B Location in patent: Paragraph 0095; 0096; 0097

78
[ 760-93-0 ]
(3S)-hydroxy-γ-butyrolactone [ No CAS ]
γ-butyrolactone-3-yl methacrylate [ No CAS ]
[ 497-23-4 ]

Yield	Reaction Conditions	Operation in experiment
1: 55% 2: 21%	With 2,6-di-tert-butyl-4-methyl-phenol; sodium carbonate In toluene at 50℃; for 4h;	1 Synthesis of γ-butyrolactone-3-yl methacrylate In a glass flask equipped with a stirrer, a thermometer and a Dimroth condenser,1.53 g (15 mmol) of (S) -3-hydroxy-γ-butyrolactone (manufactured by Tokyo Chemical Industry Co., Ltd.)2.77 g (18 mmol) of methacrylic acid anhydride (purified by Wako Pure Chemical Industries, Ltd., purified by distillation)10.40 g (12 ml) of toluene (manufactured by Wako Pure Chemical Industries, Ltd.)0.06 g (1.5 mmol) of magnesium oxide (manufactured by Wako Pure Chemical Industries, Ltd.) (electronegativity of magnesium ... 1.31)0.034 g of BHT (dibutylhydroxytoluene) (manufactured by Wako Pure Chemical Industries, Ltd.) was charged.Then, the mixture was heated and stirred at 50 ° C. for 4 hours to perform an esterification reaction.The content of γ-butyrolactone-3-yl methacrylate (target product) in the reaction solution after completion of heating was 1.27 g,The reaction yield was 50% (based on (S) -3-hydroxy-γ-butyrolactone).In addition, the content of crotonolactone which is a reaction by-product (β-elimination product of ester) was 0.09 g, and the reaction yield was 7%.

Reference： [1]Current Patent Assignee: Mitsubishi Chemical Corp (in: MCHC Group); MITSUBISHI CHEMICAL HOLDINGS CORPORATION - JP6103296, 2017, B2 Location in patent: Paragraph 0033

79
[ 227305-67-1 ]
[ 497-23-4 ]
4-(3-(2-methoxyethoxy)phenyl)dihydrofuran-2(3H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
99%	With chloro(1,5-cyclooctadiene)rhodium(I) dimer; (R)-2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl In 1,4-dioxane at 100℃; for 1h; Microwave irradiation;	Addition of 6a to 7 in the presence of [RhCl(cod)]2 and (R)-BINAP A solution of [RhCl(cod)]2 (49.3 mg, 0.100 mmol), (R)-BINAP(125 mg, 0.200 mmol) and 6a (980 mg, 5.00 mmol) in 1,4-dioxane(10 mL) was treated with 7 (0.142 mL, 2.0 mmol) and the mixture was heated to 100 C for 1 h in a microwave reactor. The reactionmixture was allowed to cool and partitioned between water(20 mL) and DCM (20 mL). The layers were separated and theorganic layer was passed through a hydrophobic frit and concentratedin vacuo. The residue was purified by chromatography ona KPNH (50 g) cartridge eluting with a gradient of 0-100% TBMEin cyclohexane over 45 min. The relevant fractions were concentratedin vacuo to give (±)-5a (467 mg, 99%) as a colourless oil:LCMS (System A) RT = 0.80 min, 98%, ES+ve m/z 237 (M+H)+, 254(M+NH4)+. Anal. Chiral HPLC RT = 9.70 min, 47.8% andRT = 11.94 min, 52.2% on a Chiralpak AD column(4.6 mm 250 mm), eluting with 40% EtOH-heptane, flow-rate1 mL/min, detecting at 215 nm.

Reference： [1]Procopiou, Panayiotis A.; Barrett, Tim N.; Copley, Royston C.B.; Tame, Christopher J. [Tetrahedron Asymmetry, 2017, vol. 28, # 10, p. 1384 - 1393]

80
[ 863377-22-4 ]
[ 497-23-4 ]
(S)-4-(3-morpholinophenyl)dihydrofuran-2(3H)-one [ No CAS ]
(R)-4-(3-morpholinophenyl)dihydrofuran-2(3H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	With bis(norbornadiene)rhodium(l)tetrafluoroborate; (R)-2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl; potassium hydroxide; In 1,4-dioxane; water; at 100℃; for 1h;Microwave irradiation;	A solution of [Rh(nbd)2]BF4 (18.70 mg, 0.05 mmol), (R)-BINAP(62.3 mg, 0.1 mmol) and <strong>[863377-22-4](3-morpholinophenyl)boronic acid</strong> 6b(1.035 g, 5.00 mmol) in 1,4-dioxane (10 mL) was treated with 7(0.142 mL, 2.0 mmol) and KOH solution (3.8 M, 1.053 mL,4.00 mmol). The resulting solution was heated to 100 C for 1 hin a microwave reactor, allowed to cool and concentrated in vacuo.The residue was purified by chromatography (50 g KPNH cartridge)eluting with a gradient of 0?50percent EtOAc in cyclohexane over45 min. The relevant fractions were concentrated in vacuo to give(R)-5b (132 mg, 27percent) as a white solid: LCMS (System B)RT = 0.82 min, 100percent, ES+ve m/z 248 (M+H)+; HRMS (ESI) calc?d for C14H18NO3 (M+H)+ 248.1281, found 248.1283. [a]D22 = 28 (c 1.70,CHCl3). Anal. Chiral HPLC RT = 23.4 min, 94percent, RT = 25.4 min 6percent ona Chiralpak ID column (250 mm 4.6 mm) eluting with 20percent isopropanol?heptane, flow-rate 1 mL/min, detecting at 215 nm

Reference： [1]Tetrahedron Asymmetry,2017,vol. 28,p. 1384 - 1393

81
[ 1049730-10-0 ]
[ 497-23-4 ]
4-(3-cyclopropylphenyl)dihydrofuran-2(3H)-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
57%	With chloro(1,5-cyclooctadiene)rhodium(I) dimer; potassium hydroxide In 1,4-dioxane; water at 20℃; for 0.166667h; Inert atmosphere;	1 (±)-4-(3-Cyclopropylphenyl)dihydrofuran-2(3H)-one(±)-5d A nitrogen-degassed mixture of 6d (100 mg, 0.62 mmol) and 7 (0.22 mL, 3.1 mmol) in 1,4-dioxane (2 mL) and water (0.2 mL) was treated with [RhCl(cod)]2 (30 mg, 60 μmol) and aqueous 3.8 M KOH solution (0.49 mL, 1.9 mmol) sequentially at room temperature and the reaction mixture was stirred at room temperature for 10 min. Water (10 mL) and EtOAc (10 mL) were added and the separated aqueous phase was extracted twice with EtOAc (2 * 10 mL). The combined organic phase was passed through a hydrophobic frit and the filtrate was concentrated under reduced pressure. The residue was purified by chromatography on a silica column (20 g) eluting with 0-50% EtOAc in cyclohexane over 40 min. The relevant fractions were combined and concentrated under reduced pressure to afford (+-)-5d (71 mg, 57%) as a clear oil: LCMS (System A) RT = 1.00 min, ES+ve m/z 203 (M+H)+; IR νmax (neat) 1771, 1164, 1015 cm-1; 1H NMR (CD3CN, 400 MHz) 7.14 (1H, t, J = 8 Hz), 7.06-6.99 (2H, m), 6.90 (1H, d, J = 8 Hz), 4.55 (1H, t, J = 8 Hz), 4.12 (1H, t, J = 8 Hz), 3.74 (1H, quin, J = 8.5 Hz), 2.77 (1H, dd, J = 17, 8.5 Hz), 2.62 (1H, dd, J = 17, 9.5 Hz), 1.86-1.78 (1H, m), 0.86 (2H, ddd, J = 8, 4.5, 2 Hz), 0.64-0.56 (2H, m); 13C NMR (DMSO-d6, 101 MHz) 177.1, 144.7, 140.2, 129.0, 124.8, 124.5, 124.4, 73.9, 41.0, 35.6, 15.5, 9.9. HRMS (ESI) calc'd for C13H15O2 (M+H)+ 203.1072, found 203.1065.

Reference： [1]Procopiou, Panayiotis A.; Barrett, Tim N.; Copley, Royston C.B.; Tame, Christopher J. [Tetrahedron Asymmetry, 2017, vol. 28, # 10, p. 1384 - 1393]

82
[ 497-23-4 ]
[ 99-94-5 ]
[ 16304-70-4 ]

Yield	Reaction Conditions	Operation in experiment
73%	With dipotassium hydrogenphosphate; [4,4′-bis(1,1-dimethylethyl)-2,2′-bipyridine-N1,N1′]bis{3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridinyl-κN]phenyl-κC}iridium(III) hexafluorophosphate; triphenylphosphine In dichloromethane; water at 20℃; Inert atmosphere; Irradiation;	71 Example 71 Firstly weighing (27.2 mg, 0.2 mmol),photocatalyst Ir[dF(CF3)ppy]2(dtbbpy)PF6(2.3 mg, 0.002 mmol), K2HPO4(7.0 mg, 0.04 mmol), and Ph3P (62.9 mg, 0.24 mmol) are added to a reaction tube, pumping air through the vacuum line three times, in the argon atmosphere, adding DCM/H2O (2.0 ml, 4:1 v/v), then carefully added (25.2 mg, 0.3 mmol),then put into 5W blue LEDs lamp irradiation, react at room temperature for 36 - 60 h. Add 20 ml water, and the DCM extraction (3x 10 ml) the aqueous phase, combined with the organic phase. The organic phase by absolute Na2SO4 after drying and steaming and to remove the solvent, dry sample, column chromatography (300 - 400 item of chromatographic analysis silica gel) (petroleum ether - ethyl acetate) to obtain the product 29.8 mg, Yield 73%.

Reference： [1]Current Patent Assignee: NANJING UNIVERSITY - CN108912042, 2018, A Location in patent: Paragraph 0158; 0159

83
[ 98-01-1 ]
[ 497-23-4 ]
[ 110-16-7 ]

Yield	Reaction Conditions	Operation in experiment
1: 71% 2: 11%	With dihydrogen peroxide; acetic acid In water at 60℃; for 24h; Green chemistry;
1: 51.9% 2: 7.1%	With dihydrogen peroxide; potassium bromide; potassium hydroxide In water at 100℃; for 3h;	2.2. Experimental procedure All catalytic oxidation reactions were conducted in a 15 ml thickwalledglass tube. Typically, 1 mmol furfural, 0.5 mmol KBr, 0.5mmol mg KOH, 2 ml distilled water (DIW), and 1 ml H2O2 were addedinto the glass tube. Then the tube was heated in a preheated oil bath withmagnetic stirring. After the specified reaction time elapsed, the tube wasput in flowing water to end the reaction. Finally, the resultant productswere stored in a 4 C refrigerator for further analysis.

Reference： [1]Zvarych, Viktor; Nakonechna, Anna; Marchenko, Mykhailo; Khudyi, Oleksii; Lubenets, Vira; Khuda, Lidiia; Kushniryk, Olga; Novikov, Volodymyr [Journal of Agricultural and Food Chemistry, 2019, vol. 67, # 11, p. 3114 - 3117]
[2]Yang, Tao; Li, Wenzhi; Ogunbiyi, Ajibola T. [Molecular catalysis, 2021, vol. 504]

84
[ 75233-61-3 ]
[ 497-23-4 ]
C₁₁H₁₅NO₅ [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
47%	With phenyl isocyanate; N-ethyl-N,N-diisopropylamine In toluene for 4h; Reflux;	1.1 Step 1: Synthesis of Compound 1’-2 To a solution of gamma-Crotonolactone 1’-1 (4.80 g, 57.1 mmol) and phenyl isocyanate (12.4 ml, 114 mmol) in toluene (72 ml) were added 2-(2-nitroethoxy)tetrahydro-2H-pyran (15.0 g, 86.0 mmol) and DIPEA (0.499 ml, 2.85 mmol) in toluene (24 ml) at 110 °C. After stirring for 3 hours at reflux temperature, the reaction mixture was added to DIPEA (0.499 ml, 2.85 mmol). After stirring for 1 h at reflux temperature, the reaction mixture was cooled to room temperature. The mixture was filtered through Celite (Registered trademark) pad and the filtrate was concentrated in vacuo. The crude product was added to a silica gel column and eluted with hexane/EtOAc 20% to 50%. Collected fractions were evaporated to afford Compound 1-2 (6.50 g, 26.9 mmol, 47 %) as a brown oil. 1H NMR (CDCl 3) δ: 1.57-1.90 (6H, m), 3.51-3.62 (1H, m), 3.90 (1H, dt, J = 38.1, 9.9 Hz), 4.33-4.48 (2H, m), 4.54-4.79 (4H, m), 5.56-5.49 (1H, m).
47%	With phenyl isocyanate; N-ethyl-N,N-diisopropylamine In toluene at 110℃; for 4h;	1.1 Step 1: Synthesis of Compound 1-2 To a solution of gamma-Crotonolactone 1-1 (4.80 g, 57.1 mmol) and phenyl isocyanate (12.4 ml, 114 mmol) in toluene (72 ml) were added 2-(2-nitroethoxy)tetrahydro-2H-pyran (15.0 g, 86.0 mmol) and DIPEA (0.499 ml, 2.85 mmol) in toluene (24 ml) at 110 °C. After stirring for 3 hours at reflux temperature, the reaction mixture was added to DIPEA (0.499 ml, 2.85 mmol). After stirring for 1 h at reflux temperature, the reaction mixture was cooled to room temperature. The mixture was filtered through Celite (Registered trademark) pad and the filtrate was concentrated in vacuo. The crude product was added to a silica gel column and eluted with hexane/EtOAc 20% to 50%. Collected fractions were evaporated to afford Compound 1-2 (6.50 g, 26.9 mmol, 47 %) as a brown oil. H NMR (CDCl ) δ: 1.57-1.90 (6H, m), 3.51-3.62 (1H, m), 3.90 (1H, dt, J = 38.1, 9.9 Hz), 4.33-4.48 (2H, m), 4.54-4.79 (4H, m), 5.56-5.49 (1H, m).

Reference： [1]Current Patent Assignee: SHIONOGI & CO., LTD. - WO2019/208509, 2019, A1 Location in patent: Paragraph 0097
[2]Current Patent Assignee: SHIONOGI & CO., LTD. - WO2020/9179, 2020, A1 Location in patent: Paragraph 0056-0057

85
[ 17877-17-7 ]
[ 591-50-4 ]
[ 497-23-4 ]
C₁₆H₂₁NO₂ [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
62%	With (1,2-dimethoxyethane)dichloronickel(II); bis(2-phenylpyridinato)(2,2'-bipyridine)iridium(III) hexafluorophosphate; 4,4'-Dimethoxy-2,2'-bipyridin In N,N-dimethyl-formamide at 20℃; for 15h; Sealed tube; Inert atmosphere; Irradiation;	14 Example 14 Add a magnetic stir bar, photocatalyst Ir(ppy)2(bpy)PF6 (2.4mg, 3.0μmol, 0.010 equivalent), metal catalyst NiCl2·glyme (6.6mg, 30μmol, 0.10 equivalent) into a 10mL transparent glass reaction tube,Ligand di(OMe)bpy (6.1mg, 30μmol, 0.10 equivalent), seal the mouth of the tube with a rubber stopper, protect the reaction system with nitrogen (pump and vent three times), inject the solvent anhydrous DMF (3.0mL) into the syringe, and then use a small amount Add α-aminomethyl silicon 1a (0.12mL, 0.10g, 0.60mmol, 2.0 equivalent), furan-2(5H)-one 2f (50mg, 0.60mmol, 2.0 equivalent), iodobenzene 3a (33μL, 61mg, 0.30mmol, 1.0 equivalent), placed under blue light irradiation at room temperature for 15 hours, then quenched with water, extracted with ethyl acetate (20mL x 3 times), combined the organic phases, dried over anhydrous sodium sulfate, filtered, spin-dried, column The product 17 was obtained by chromatography (16 mg, yield 20%).

Reference： [1]Current Patent Assignee: HUAZHONG UNIVERSITY OF SCIENCE & TECHNOLOGY - CN111559992, 2020, A Location in patent: Paragraph 0085-0086

86
[ 22383-85-3 ]
[ 497-23-4 ]
C₁₅H₁₈O₆ [ No CAS ]
C₁₅H₁₈O₆ [ No CAS ]

Reference： [1]Angewandte Chemie - International Edition,2021,vol. 60,p. 16655 - 16660
Angew. Chem.,2021,vol. 133,p. 16791 - 16796

87
[ 497-23-4 ]
2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decane [ No CAS ]
4-{2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decan-9-yl}oxolan-2-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
72%		3 Step 3: Step 3: Synthesis of 4-{2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decan-9-yl}oxolan-2-one A mixture of 2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decane (999.91 mg, 3.31 mmol) and 2,5-dihydrofuran-2-one (556.19 mg, 6.62 mmol) in MeOH (2.0 ml) was stirred at room temperature overnight. The mixture was evaporated in vacuo, the residue was dissolved in MTBE (50 mL), washed with water (2 * 50 mL), brine (30 mL) and evaporated to afford 4-2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decan-9-yloxolan-2-one (920.0 mg, 2.38 mmol, 72% yield) as a brown oil.
72%		3 Step 3: Step 3: Synthesis of 4-{2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decan-9-yl}oxolan-2-one A mixture of 2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decane (999.91 mg, 3.31 mmol) and 2,5-dihydrofuran-2-one (556.19 mg, 6.62 mmol) in MeOH (2.0 ml) was stirred at room temperature overnight. The mixture was evaporated in vacuo, the residue was dissolved in MTBE (50 mL), washed with water (2 * 50 mL), brine (30 mL) and evaporated to afford 4-2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decan-9-yloxolan-2-one (920.0 mg, 2.38 mmol, 72% yield) as a brown oil.
72%	With methanol at 20℃;	5.3 Step 3: Synthesis of 4-{2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decan-9-yl}oxolan-2-one A mixture of 2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decane (999.91 mg, 3.31 mmol) and 2,5-dihydrofuran-2-one (556.19 mg, 6.62 mmol) in MeOH (2.0 ml) was stirred at room temperature overnight. The mixturewas evaporated in vacuo, the residue was dissolved in MTBE (50 mL), washed with water (2 3 50 mL), brine (30 mL) and evaporated to afford 4-2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decan-9-yloxolan-2-one (920.0 mg,2.38 mmol, 72% yield) as a brown oil.

72%

With methanol at 20℃;

5.3 Step 3: Synthesis of 4-{2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decan-9-yl}oxolan-2-one A mixture of 2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decane (999.91 mg, 3.31 mmol) and 2,5-dihydrofuran-2-one (556.19 mg, 6.62 mmol) in MeOH (2.0 ml) was stirred at room temperature overnight. The mixturewas evaporated in vacuo, the residue was dissolved in MTBE (50 mL), washed with water (2 3 50 mL), brine (30 mL) and evaporated to afford 4-2-[4-(trifluoromethoxy)phenyl]-6-oxa-2,9-diazaspiro[4.5]decan-9-yloxolan-2-one (920.0 mg,2.38 mmol, 72% yield) as a brown oil.

Reference： [1]Current Patent Assignee: ABARCEO - EP3945091, 2022, A1
[2]Current Patent Assignee: ABARCEO - EP3945091, 2022, A1
[3]Current Patent Assignee: ABARCEO - EP3945091, 2022, A1 Location in patent: Paragraph 0147-0148
[4]Current Patent Assignee: ABARCEO - EP3945091, 2022, A1 Location in patent: Paragraph 0147-0148

88
[ 497-23-4 ]
2-[4-(trifluoromethoxy)phenyl]-1H,2H,3H,4H,5H,6H-pyrrolo[3, 4-c]pyrrole [ No CAS ]
4-{5-[4-(trifluoromethoxy)phenyl]-1H,2H,3H,4H,5H,6H-pyrrolo[3,4-c]pyrrol-2-yl}oxolan-2-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
87.1%	In methanol at 20℃;	4.3 Step 3: Synthesis of 4-{5-[4-(trifluoromethoxy)phenyl]-1H,2H,3H,4H,5H,6H-pyrrolo[3,4-c]pyrrol-2-yl}oxolan-2-one A mixture of 2-[4-(trifluoromethoxy)phenyl]-1H,2H,3H,4H,5H,6H-pyrrolo[3,4-c]pyrrole (1.4 g, 5.18 mmol) and 2,5-dihydrofuran-2-one (871.29 mg, 10.36 mmol) in MeOH (3.1 mL) was stirred at room temperature overnight. The mixture was evaporated in vacuo, residue treated with water (20 mL), filtered, washed with water (2 3 20 mL), hexane(30 mL) and dried to afford 4-{5-[4-(trifluoromethoxy)phenyl]-1H,2H,3H,4H,5H,6H-pyrrolo[3,4-c]pyrrol-2-yl}oxolan-2-one(1.6 g, 4.52 mmol, 87.1% yield) as a yellow solid .
87.1%	In methanol at 20℃;	4.3 Step 3: Synthesis of 4-{5-[4-(trifluoromethoxy)phenyl]-1H,2H,3H,4H,5H,6H-pyrrolo[3,4-c]pyrrol-2-yl}oxolan-2-one A mixture of 2-[4-(trifluoromethoxy)phenyl]-1H,2H,3H,4H,5H,6H-pyrrolo[3,4-c]pyrrole (1.4 g, 5.18 mmol) and 2,5-dihydrofuran-2-one (871.29 mg, 10.36 mmol) in MeOH (3.1 mL) was stirred at room temperature overnight. The mixture was evaporated in vacuo, residue treated with water (20 mL), filtered, washed with water (2 3 20 mL), hexane(30 mL) and dried to afford 4-{5-[4-(trifluoromethoxy)phenyl]-1H,2H,3H,4H,5H,6H-pyrrolo[3,4-c]pyrrol-2-yl}oxolan-2-one(1.6 g, 4.52 mmol, 87.1% yield) as a yellow solid .

Reference： [1]Current Patent Assignee: ABARCEO - EP3945091, 2022, A1 Location in patent: Paragraph 0137-0138
[2]Current Patent Assignee: ABARCEO - EP3945091, 2022, A1 Location in patent: Paragraph 0137-0138

Purity	Size	Price	VIP Price	USA Stock *0-1 Day	Global Stock *5-7 Days	Quantity
{[ item.p_purity ]}	{[ item.pr_size ]}	{[ getRatePrice(item.pr_usd, 1,1) ]} {[ getRatePrice(item.pr_usd,item.pr_rate,item.mem_rate) ]}	{[ getRatePrice(item.pr_usd, 1,1) ]}	Inquiry {[ getRatePrice(item.pr_usd,item.pr_rate,item.mem_rate) ]} {[ getRatePrice(item.pr_usd,1,item.mem_rate) ]}	{[ item.pr_usastock ]}	Inquiry -	{[ item.pr_chinastock ]}	Inquiry -

CAS No. :	497-23-4	MDL No. :	MFCD00005376
Formula :	C₄H₄O₂	Boiling Point :	-
Linear Structure Formula :	-	InChI Key :	VIHAEDVKXSOUAT-UHFFFAOYSA-N
M.W :	84.07	Pubchem ID :	10341
Synonyms :	γ-Crotonolactone	Chemical Name :	Furan-2(5H)-one

Num. heavy atoms :	6
Num. arom. heavy atoms :	0
Fraction Csp3 :	0.25
Num. rotatable bonds :	0
Num. H-bond acceptors :	2.0
Num. H-bond donors :	0.0
Molar Refractivity :	20.04
TPSA :	26.3 Å²

GI absorption :	High
BBB permeant :	No
P-gp substrate :	No
CYP1A2 inhibitor :	No
CYP2C19 inhibitor :	No
CYP2C9 inhibitor :	No
CYP2D6 inhibitor :	No
CYP3A4 inhibitor :	No
Log Kp (skin permeation) :	-7.24 cm/s

Log Po/w (iLOGP) :	1.1
Log Po/w (XLOGP3) :	-0.6
Log Po/w (WLOGP) :	0.1
Log Po/w (MLOGP) :	-0.01
Log Po/w (SILICOS-IT) :	1.02
Consensus Log Po/w :	0.32

[ CAS No. 497-23-4 ] {[proInfo.proName]}

Quality Control of [ 497-23-4 ]

Related Doc. of [ 497-23-4 ]

Product Details of [ 497-23-4 ]

Calculated chemistry of [ 497-23-4 ]

Physicochemical Properties

Pharmacokinetics

Lipophilicity

Druglikeness

Water Solubility

Medicinal Chemistry

Safety of [ 497-23-4 ]

Application In Synthesis of [ 497-23-4 ]

[ 497-23-4 ] Synthesis Path-Upstream 1~3

[ 497-23-4 ] Synthesis Path-Downstream 1~88

Related Functional Groups of
[ 497-23-4 ]

Esters

Related Parent Nucleus of
[ 497-23-4 ]

Furans

Precautionary Statements-General

Prevention

Response

Storage

Disposal

Physical hazards

Health hazards

Environmental hazards

Inquiry

Lipinski :	0.0
Ghose :	None
Veber :	0.0
Egan :	0.0
Muegge :	2.0
Bioavailability Score :	0.55

Log S (ESOL) :	0.02
Solubility :	87.4 mg/ml ; 1.04 mol/l
Class :	Highly soluble
Log S (Ali) :	0.52
Solubility :	278.0 mg/ml ; 3.3 mol/l
Class :	Highly soluble
Log S (SILICOS-IT) :	-0.04
Solubility :	76.7 mg/ml ; 0.912 mol/l
Class :	Soluble

PAINS :	0.0 alert
Brenk :	0.0 alert
Leadlikeness :	1.0
Synthetic accessibility :	1.9

Signal Word:	Warning	Class:	N/A
Precautionary Statements:	P261-P305+P351+P338	UN#:	N/A
Hazard Statements:	H315-H319-H335	Packing Group:	N/A
GHS Pictogram:

Precautionary Statements-General
Code	Phrase
P101	If medical advice is needed,have product container or label at hand.
P102	Keep out of reach of children.
P103	Read label before use
Prevention
Code	Phrase
P201	Obtain special instructions before use.
P202	Do not handle until all safety precautions have been read and understood.
P210	Keep away from heat/sparks/open flames/hot surfaces. - No smoking.
P211	Do not spray on an open flame or other ignition source.
P220	Keep/Store away from clothing/combustible materials.
P221	Take any precaution to avoid mixing with combustibles
P222	Do not allow contact with air.
P223	Keep away from any possible contact with water, because of violent reaction and possible flash fire.
P230	Keep wetted
P231	Handle under inert gas.
P232	Protect from moisture.
P233	Keep container tightly closed.
P234	Keep only in original container.
P235	Keep cool
P240	Ground/bond container and receiving equipment.
P241	Use explosion-proof electrical/ventilating/lighting/equipment.
P242	Use only non-sparking tools.
P243	Take precautionary measures against static discharge.
P244	Keep reduction valves free from grease and oil.
P250	Do not subject to grinding/shock/friction.
P251	Pressurized container: Do not pierce or burn, even after use.
P260	Do not breathe dust/fume/gas/mist/vapours/spray.
P261	Avoid breathing dust/fume/gas/mist/vapours/spray.
P262	Do not get in eyes, on skin, or on clothing.
P263	Avoid contact during pregnancy/while nursing.
P264	Wash hands thoroughly after handling.
P265	Wash skin thouroughly after handling.
P270	Do not eat, drink or smoke when using this product.
P271	Use only outdoors or in a well-ventilated area.
P272	Contaminated work clothing should not be allowed out of the workplace.
P273	Avoid release to the environment.
P280	Wear protective gloves/protective clothing/eye protection/face protection.
P281	Use personal protective equipment as required.
P282	Wear cold insulating gloves/face shield/eye protection.
P283	Wear fire/flame resistant/retardant clothing.
P284	Wear respiratory protection.
P285	In case of inadequate ventilation wear respiratory protection.
P231 + P232	Handle under inert gas. Protect from moisture.
P235 + P410	Keep cool. Protect from sunlight.
Response
Code	Phrase
P301	IF SWALLOWED:
P304	IF INHALED:
P305	IF IN EYES:
P306	IF ON CLOTHING:
P307	IF exposed:
P308	IF exposed or concerned:
P309	IF exposed or if you feel unwell:
P310	Immediately call a POISON CENTER or doctor/physician.
P311	Call a POISON CENTER or doctor/physician.
P312	Call a POISON CENTER or doctor/physician if you feel unwell.
P313	Get medical advice/attention.
P314	Get medical advice/attention if you feel unwell.
P315	Get immediate medical advice/attention.
P320
P302 + P352	IF ON SKIN: wash with plenty of soap and water.
P321
P322
P330	Rinse mouth.
P331	Do NOT induce vomiting.
P332	IF SKIN irritation occurs:
P333	If skin irritation or rash occurs:
P334	Immerse in cool water/wrap n wet bandages.
P335	Brush off loose particles from skin.
P336	Thaw frosted parts with lukewarm water. Do not rub affected area.
P337	If eye irritation persists:
P338	Remove contact lenses, if present and easy to do. Continue rinsing.
P340	Remove victim to fresh air and keep at rest in a position comfortable for breathing.
P341	If breathing is difficult, remove victim to fresh air and keep at rest in a position comfortable for breathing.
P342	If experiencing respiratory symptoms:
P350	Gently wash with plenty of soap and water.
P351	Rinse cautiously with water for several minutes.
P352	Wash with plenty of soap and water.
P353	Rinse skin with water/shower.
P360	Rinse immediately contaminated clothing and skin with plenty of water before removing clothes.
P361	Remove/Take off immediately all contaminated clothing.
P362	Take off contaminated clothing and wash before reuse.
P363	Wash contaminated clothing before reuse.
P370	In case of fire:
P371	In case of major fire and large quantities:
P372	Explosion risk in case of fire.
P373	DO NOT fight fire when fire reaches explosives.
P374	Fight fire with normal precautions from a reasonable distance.
P376	Stop leak if safe to do so. Oxidising gases (section 2.4) 1
P377	Leaking gas fire: Do not extinguish, unless leak can be stopped safely.
P378
P380	Evacuate area.
P381	Eliminate all ignition sources if safe to do so.
P390	Absorb spillage to prevent material damage.
P391	Collect spillage. Hazardous to the aquatic environment
P301 + P310	IF SWALLOWED: Immediately call a POISON CENTER or doctor/physician.
P301 + P312	IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.
P301 + P330 + P331	IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.
P302 + P334	IF ON SKIN: Immerse in cool water/wrap in wet bandages.
P302 + P350	IF ON SKIN: Gently wash with plenty of soap and water.
P303 + P361 + P353	IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.
P304 + P312	IF INHALED: Call a POISON CENTER or doctor/physician if you feel unwell.
P304 + P340	IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.
P304 + P341	IF INHALED: If breathing is difficult, remove victim to fresh air and keep at rest in a position comfortable for breathing.
P305 + P351 + P338	IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P306 + P360	IF ON CLOTHING: Rinse Immediately contaminated CLOTHING and SKIN with plenty of water before removing clothes.
P307 + P311	IF exposed: call a POISON CENTER or doctor/physician.
P308 + P313	IF exposed or concerned: Get medical advice/attention.
P309 + P311	IF exposed or if you feel unwell: call a POISON CENTER or doctor/physician.
P332 + P313	IF SKIN irritation occurs: Get medical advice/attention.
P333 + P313	IF SKIN irritation or rash occurs: Get medical advice/attention.
P335 + P334	Brush off loose particles from skin. Immerse in cool water/wrap in wet bandages.
P337 + P313	IF eye irritation persists: Get medical advice/attention.
P342 + P311	IF experiencing respiratory symptoms: call a POISON CENTER or doctor/physician.
P370 + P376	In case of fire: Stop leak if safe to Do so.
P370 + P378	In case of fire:
P370 + P380	In case of fire: Evacuate area.
P370 + P380 + P375	In case of fire: Evacuate area. Fight fire remotely due to the risk of explosion.
P371 + P380 + P375	In case of major fire and large quantities: Evacuate area. Fight fire remotely due to the risk of explosion.
Storage
Code	Phrase
P401
P402	Store in a dry place.
P403	Store in a well-ventilated place.
P404	Store in a closed container.
P405	Store locked up.
P406	Store in corrosive resistant/ container with a resistant inner liner.
P407	Maintain air gap between stacks/pallets.
P410	Protect from sunlight.
P411
P412	Do not expose to temperatures exceeding 50 oC/ 122 oF.
P413
P420	Store away from other materials.
P422
P402 + P404	Store in a dry place. Store in a closed container.
P403 + P233	Store in a well-ventilated place. Keep container tightly closed.
P403 + P235	Store in a well-ventilated place. Keep cool.
P410 + P403	Protect from sunlight. Store in a well-ventilated place.
P410 + P412	Protect from sunlight. Do not expose to temperatures exceeding 50 oC/122oF.
P411 + P235	Keep cool.
Disposal
Code	Phrase
P501	Dispose of contents/container to ...
P502	Refer to manufacturer/supplier for information on recovery/recycling

[ CAS No. 497-23-4 ] {[proInfo.proName]}

Quality Control of [ 497-23-4 ]

Related Doc. of [ 497-23-4 ]

Product Details of [ 497-23-4 ]

Calculated chemistry of [ 497-23-4 ]

Physicochemical Properties

Pharmacokinetics

Lipophilicity

Druglikeness

Water Solubility

Medicinal Chemistry

Safety of [ 497-23-4 ]

Application In Synthesis of [ 497-23-4 ]

[ 497-23-4 ] Synthesis Path-Upstream 1~3

[ 497-23-4 ] Synthesis Path-Downstream 1~88

Related Functional Groups of [ 497-23-4 ]

Esters

Related Parent Nucleus of [ 497-23-4 ]

Furans

Precautionary Statements-General

Prevention

Response

Storage

Disposal

Physical hazards

Health hazards

Environmental hazards

Inquiry

Related Functional Groups of
[ 497-23-4 ]

Related Parent Nucleus of
[ 497-23-4 ]