反应详情

The present invention is related to a process for the preparation of [1,4′]bipiperidinyl-1′-carbonyl chloride or its hydrochloride, which is a useful intermediate e.g. in the preparation of irinotecan. The use of methylene chloride as a solvent in the reaction of 4-piperidinopiperidine with phosgene and the removal of the reaction solvent by using an additional distillation solvent to raise the distillation temperature gives [1,4′]bipiperidinyl-1′-carbonyl chloride hydrochloride in high yield and purity. The amount of dimer impurity will be less than 5%, even less than 1%.

1. customthe removal of the reaction solvent
2. temperatureto raise the distillation temperature