反应详情

Zinc powder (40 g) was added to a solution of 7-aminocephalosporanic acid (27.3 g) and conc. hydrochloric acid (70 ml.) in water (200 ml.) for 5° C. and stirred for an hour. The resultant solution was adjusted to pH 4.0 with 4 N sodium hydroxide and concentrated to 100 ml. of the volume. After adjusting the solution to pH 4.0, the solution was allowed to stand under cooling overnight. The precipitates were collected by filtration to give 7-amino-3-methylenecepham-4-carboxylic acid (11.96 g.).

1. concentrationconcentrated to 100 ml
2. temperatureunder cooling overnight
3. filtrationThe precipitates were collected by filtration