反应详情

Finally, DE-A-No. 3,602,377 discloses a process for preparing caprolactam wherein the 5-formylvaleric ester is initially hydrolyzed with water in the presence of a catalyst from 30° to 200° C. to 5-formylvaleric acid which is reacted with ammonia and hydrogen in the presence of a solvent and hydrogenation catalyst under a superatmospheric pressure at from 50° to 150° C. to give 6-aminocaproic acid, the ammonia and the catalyst are separated off, and the resulting solution of 6-aminocaproic acid is heated to 150°-370° C. to form caprolactam. For this process to be practised in industry, the yields must be improved. Moreover, this process requires an additional hydrolysis stage.