Diisopropylamine → Lithium diisopropylamide

Participants

Reaction Conditions

Reaction Steps

Lithium di-isopropylamide was prepared by dissolving di-isopropylamine (11 ml) in tetrahydrofuran (150 ml) followed by the addition of n-butyl lithium (50 ml of 1.7 molar). After 10 minutes stirring, the straw colored liquid was cooled to -78° C. and a solution of 2-(4-chlorophenoxy)-N,N-dimethyl acetamide (16 g, 0.074 mole) in tetrahydrofuran (25 ml) was slowly added. The mixture was stirred for 20 minutes at -78° C. and cyclohexanone (7 ml) added. After 45 minutes at -78° C., the reaction mixture was poured into saturated ammonium chloride solution and a red color ensued. The phases were separated and the organic layer washed with brine, dried over anhydrous potassium carbonate and evaporated giving 1-[(4-chlorophenoxy)((dimethylamino)carbonyl)methyl]cyclohexanol as a red solid. Repeated washing with a cold hexane-isopropanol mixture yielded 2.7 g of a white crystalline solid. Yield: 2.7 g, m.p. 109°-111° C.

Provenance & Evidence