Dichloromethane → (3S,4S)-1-(allyloxyoxalyl)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[(1R)-1-{(methylthio)thiocarbonyl}ethyl]-2-oxoazetidine

Participants

Reaction Steps

To a mixture of dichloromethane (32.6 mg) and a mixture (33.1 mg) of (3S,4S)-3-[(1R)-1-(tertbutyldimethylsilyloxy)ethyl]-4-[(1R)-1-{(methylthio)thiocarbonyl}ethyl]-2-oxoazetidine and (3S,4S)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[(1S)-1-{(methylthio)thiocarbonyl}ethyl]-2-oxoazetidine were added triethylamine (30.4 mg) and allyl chloroglyoxylate (32.6 mg) successively at 0° C. After stirring for 10 minutes at the same temperature, the solution was washed with water, 1N hydrochloric acid, brine, and dried. The solvent was removed under reduced pressure and the residue was purified by flash chromatography (5% diethyl ether-hexane) to afford a mixture (23 mg) of (3S,4S)-1-(allyloxyoxalyl)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[(1R)-1-{(methylthio)thiocarbonyl}ethyl]-2-oxoazetidine and (3S,4S)-1-(allyloxyoxalyl)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[1S)-1-{(methylthio)thiocarbonyl}ethyl]-2-oxoazetidine.

Provenance & Evidence