Dimethyl Sulfoxide → Methyl 4-(piperidin-2-yl)butanoate hydrochloride

Participants

Reaction Conditions

Reaction Steps

A solution of DMSO (21.24 ml, 299 mmol) in CH2Cl2 (600 ml) was dropwise added to a solution of oxalyl chloride (15.0 ml, 171 mmol) in CH2Cl2 (300 ml) in 30 min while maintaining the internal temperature below −65° C. A solution of 3 (46.7 g, 142 mmol) in CH2Cl2 (300 ml) was added dropwise in 15 min. while maintaining the temperature below −65° C. The reaction mixture was stirred an additional 45 minutes at −78° C., after which Et3N (99.0 ml, 712 mmol) was added. After the reaction mixture was stirred at −78° C. for 45 min, the reaction mixture was allowed to warm to room temperature and stirring was continued for an additional hour. The reaction mixture was washed with H2O and brine, dried (Na2SO4) and concentrated. The residue was dissolved in Et2O, filtered and the filtrate was concentrated and crystallized (Et2O/heptane) to result in 4 (30.9 g, 67%). The mother liquor was concentrated and crystallized (Et2O/heptane) and gave extra 4 (2.27 g, 5%).

Provenance & Evidence