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General procedure: The quaternary salt (1.0 equiv.) was dissolved in distilled water to which LiNTf2 (1.1 equiv.) in minimal distilled water was added. The resulting solution was stirred at room temperature for 30 min. CH2Cl2 was added and the separated aqueous layer washed twice more with CH2Cl2. The combined organic layers were washed with cold distilled water until negative to a AgNO3 precipitate test, dried (Na2SO4), filtered, and concentrated under vacuum before drying overnight under high vacuum (0.1 mmHg at 60 C).