反应详情

To an ice-cooled solution of t-butyl 7α-amino-3-acetoxymethyl-3-cephem-4-carboxylate (4.0 g, 0.0122 mol) in 75 ml of ethanol, 16.7 ml of water and 16.7 ml of concentrated hydrochloric acid was added portionwise over 15-20 minutes sodium nitrite (1.18 g, 0.017 mol). The reaction mixture was stirred at 0°-5° C. for 2.5 hours, saturated with sodium chloride, extracted with methylene chloride, washed with water, brine, dried Na2SO4 and concentrated to give 3.1 g (73%) of t-butyl 7α-chloro-3-acetoxymethyl-3-cephem-4carboxylate.

1. extractionextracted with methylene chloride
2. washwashed with water, brine, dried Na2SO4
3. concentrationconcentrated