Synthesis of Aminocarbonyl N-Acylhydrazones by a Three-Component Reaction of Isocyanides, Hydrazonoyl Chlorides, and Carboxylic Acids.

A novel one-pot multicomponent synthesis of α-aminocarbonyl N-acylhydrazones starting from readily available hydrazonoyl chlorides, isocyanides, and carboxylic acids is reported. The strategy exploits the ability of the carboxylic acid as a third component to suppress all competing reactions between nitrile imines and isocyanides, channeling the course of the reaction toward the formation of this novel class of compounds.