Method for the preparation of hexahydroazepinones and hexahydroazepinoles

摘要

This disclosure describes two technical procedures for the high-yield synthesis of heterocyclic seven-membered ring-systems by Dieckmann-condensation avoiding usual dilution techniques and long reaction times. Thus, it significantly increases the overall yields of the pharmaceutically active ingredients azelastine and flezelastine, whose synthesis, starting from these seven-membered heterocyclic rings, is reported elsewhere. Yields range from 80-89%, avoiding waste and increasing economics of the synthesis.