Hexamethylphosphoramide → (3S,4R)-3-{N-(3-phenylpropionoyl)-L-phenylalanyl}amino-4-(2-bromo-1-phenylethoxy)-azetidin-2-one

Participants

Reaction Conditions

Reaction Steps

A mixture of (3S,4R)-3-{N-(3-phenylpropionoyl)-L-phenylalanyl}amino-4-{2-(p-toluenesulfonyl)oxy-1 -phenylethoxy}azetidin-2-one (160 mg, 0.244 mmol), lithium bromide (133 mg, 1.525 mmol) and HMPA (4 ml) was stirred at 60° C. for 1.5 hrs. The resulting mixture was diluted with ethyl acetate, washed with water, brine, and dried over sodium sulfate. After removal of solvent, the residue was purified by silica gel column chromatography using hexane-ethyl acetate (1:2) as eluent and 100 mg (3S,4R)-3-{N-(3-phenylpropionoyl)-L-phenylalanyl}amino-4-(2-bromo-1-phenylethoxy)-azetidin-2-one as white foam was obtained in 72% yield.

Provenance & Evidence