A PROCESS FOR PREPARING 3-BETA-AMINO-4-BETA-SUBSTITUTED 2-AZETIDINONES AND 3-(2,2-DIHALOGENOVINYL)-IMINO-4-BETA-SUBSTITUTED 2-AZETIDINONE AND 3-BETA-(2,2-DIHALOGENOVINYL)-AMINO-4-BETA-SUBSTITUTED 2-AZETIDINONE INTERMEDIATES

摘要

A process for preparing 3 beta -amino-4 beta -substituted-2-azetidinones, which comprises condensing a 3 alpha -amino-4 beta -substituted-2-azetidinone with a trihalogenoacetaldehyde or the reactive derivative thereof to give a 3 alpha -(2,2,2-trihalogenoethylidene)amino-4 beta -substituted-2-azetidinones, treating the latter with a base to give a 3-(2,2-dihalogenovinyl)imino-4 beta -substituted-2-azetidinone, reducing the latter with a metal hydride to give a 3 beta -(2-halogenovinyl)amino-4 beta -substituted-2-azetidinone, and hydrolyzing the latter to give the objective compound.