Dimethyl Sulfoxide → 3-Oxo-azetidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

To a −78° C. solution of 2M oxalyl chloride (31.8 mL, 63.5 mmol) in 200 mL DCM was added DMSO (9.01 mL, 127 mmol), followed by the slow addition by addition funnel of a solution of tert-butyl 3-hydroxyazetidine-1-carboxylate (10.0 g, 57.7 mmol) in 200 mL DCM. The cloudy reaction mixture was stirred at −78° C. for 15 minutes, then a solution triethylamine (32.2 mL, 231 mmol) in 40 mL DCM was added slowly by addition funnel. The reaction mixture was stirred another 15 minutes, the bath was removed, and the reaction was allowed to warm to ambient temperature and stirred for 15 hours. Water and brine were added, and the mixture was extracted with DCM. The combined extracts were dried (Na2SO4), filtered and concentrated. The crude was purified on silica gel (3-20% ethyl acetate in hexanes gradient) to give the desired product (9.0 g, 91.1% yield) as a white solid.

Provenance & Evidence