Acetic Acid → 1-Cyclohexyl-4-methyl-pyrrolidin-2-one

Participants

Reaction Conditions

Reaction Steps

Place 1-cyclohexyl-4-hydroxymethyl-pyrrolidin-2-one (Preparation 2) (2.5 g, 12.7 mmol) and triphenylphosphene (3.7 g, 13.9 mmol) in a flask and add dry N,N-dimethyl-acetamide (20 mL). Add a solution of iodine (3.2 g, 12.7 mol) in N,N-dimethyl-acetamide (3 mL). Stir reaction for 24 hours. Quench the reaction with saturated sodium bisulfite (20 mL) and extract with methylene chloride. Dry over sodium sulfate, filter, and concentrate. Dissolve crude material in acetonitrile (100 mL) and add glacial acetic acid (15 mL) and zinc (12.4 g, 190.1 mmol), then heat to 75° C. and stir for 6 hours. Cool to room temperature, filter, and partition between water and methylene chloride. Separate layers and wash methylene chloride with saturated sodium bicarbonate. Dry over sodium sulfate, filter, and concentrate. Purify by silica gel (30-40% ethyl acetate in hexane) to yield 1.0 g (45%) of the title compound. NMR (CDCl3) δ 3.94 (m, 1H), 3.45 (m, 1H), 2.88 (dd, 1H), 2.55 (dd, 1H), 2.38 (m, 1H), 2.02 (dd, 1H), 1.78 (m, 2H), 1.68 (m, 3H), 1.35 (m, 4H), 1.09 (m, 4H).

Provenance & Evidence