Imidazole → Cis-3-[(R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-trimethylsilylethynyl-2-azetidinone

Participants

Reaction Steps

Imidazole (0.2 g) and tert-butyldimethylsilyl chloride (0.3 g) are added to a solution of cis-3-[(R)-1-hydroxyethyl]-4-trimethylsilylethynyl-2-azetidinone (0.2 g) in N,N-dimethylformamide (7 ml), and the mixture is stirred at 60° C.-65° C. for 1.5 hours and then poured into a mixture of ethyl acetate (50 ml) and water (50 ml). The organic layer is separated, washed with aqueous sodium chloride, dried over magnesium sulfate and concentrated under reduced pressure, and the residue is subjected to silica gel column chromatography to give cis i.e. (3R,4S)-3-[(R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-trimethylsilylethynyl-2-azetidinone as crystals. (0.24 g).

Provenance & Evidence