Benzyl chloroformate → 1-Benzyl-3-(1-benzyloxycarbonyloxyethyl)-4-ethynyl-2-azetidinone

Participants

Reaction Steps

To a solution of 36 mg (0.16 mmol) of 1-benzyl-4-ethynyl-3-(1-hydroxyethyl)-2-azetidinone in 2 ml of methylene chloride, 30 mg (0.25 mmol) of 4,4-dimethylaminopyridine and 0.04 ml (0.25 mmol) of benzyloxycarbonyl chloride were added at -10° C. and the mixture was stirred for a night. Ice water was added to the reaction solution and the resultant was extracted three times with methylene chloride. The extract was washed with a saturated solution of NaCl, dried with anhydrous magnesium sulfate, concentrated and purified with 5 g of silica-gel column (hexane:ether 2:3) to give 40 mg of 1-benzyl-3-(1-benzyloxycarbonyloxyethyl)-4-ethynyl-2-azetidinone (yield: 69%).

Provenance & Evidence