反应详情

A cooled (-78°) solution of t-butyl (6R,7R)-3-acetoxymethyl-7-phenylacetamidoceph-3em-4-carboxylate (1.5 g.) in dry tetrahydrofuran (10 ml) was added over 3 minutes to a stirred and cooled (-78°) solution of lithium methoxide (358 mg) in dry methanol (8.8 ml) and tetrahydrofuran (50 ml) under nitrogen. t-Butyl hypochlorite (0.69 ml) was added after 3 minutes, and sitrring was continued for a further 5 minutes when the yellow solution was poured into a stirred mixture of ethyl acetate (150 ml) and water (150 ml) containing ammonium chloride (1 g) and sodium metabisulphite (1 g.). The aqueous phase was separated and extracted with ethyl acetate (50 ml) and the organic phases were combined and washed with brine (50 ml) and dried and evaporated to dryness in vacuo to give t-butyl (6R,7S)-3-acetoxymethyl-7-methoxy-7-phenylacetamidoceph-3-em-4-carboxylate (1.6 g).

1. additionwas added over 3 minutes to
2. customThe aqueous phase was separated
3. extractionextracted with ethyl acetate (50 ml)
4. washwashed with brine (50 ml)
5. customdried
6. customevaporated to dryness in vacuo