Cu(Ⅰ)-Catalyzed Three-Component Coupling of Trifluoromethyl Ketone N-Tosylhydrazones, Alkynes and Azides: Synthesis of Difluoromethylene Substituted 1,2,3-Triazoles

摘要

A CuⅠ-catalyzed three-component coupling of trifluoromethyl ketone N-tosylhydrazones,alkynes and azides has been developed.The reaction represents a straightforward method to access difluoromethylene substituted 1,2,3-triazoles.Mechanistically,it has been proposed that the reaction follows a pathway involving the formation of Cu(Ⅰ) triazolide intermediate,Cu(Ⅰ) carbene formation,migratory insertion,and β-fluoride elimination.The transformation is featured by mild conditions,wide substrate scope and high efficiency.