* All experimental methods are cited from the reference, please refer to the original source for details. We do not guarantee the accuracy of the content in the reference.
General procedure: A mixture of isatins (1, 1.0 mmol), indolin-2-ones (2, 1.0 mmol) and ZrCl4 (23 mg, 0.1 mmol) was heated in anhydrous ethanol (5 mL) under reflux. After the disappearance of the reactants (8–12 h, monitored by TLC), the mixture was slowly cooled to room temperature. The red solids precipitated and were collected by filtration, then washed by a small amount of anhydrous ethanol to deliver pure compounds 3.
Reference:
[1] Tetrahedron Letters, 2016, vol. 57, # 52, p. 5856 - 5858
[2] Bulletin de la Societe Chimique de France, 1914, vol. <4> 15, p. 335[3] Comptes Rendus Hebdomadaires des Seances de l'Academie des Sciences, 1913, vol. 156, p. 1385
2
[ 59-48-3 ]
[ 61-70-1 ]
[ 97207-47-1 ]
Reference:
[1] Chemical Communications, 2018, vol. 54, # 59, p. 8265 - 8268
3
[ 100-61-8 ]
[ 97207-47-1 ]
Reference:
[1] Advanced Synthesis and Catalysis, 2016, vol. 358, # 22, p. 3534 - 3540
4
[ 3526-43-0 ]
[ 97207-47-1 ]
Reference:
[1] Advanced Synthesis and Catalysis, 2016, vol. 358, # 22, p. 3534 - 3540