Contributions to the Chemistry of Enaminoketones, XV: The Three-Component Synthesis of Hydrazinomethylene-chromandiones and a reductive N-N Bond Cleavage of Phenylhydrazine

Article abstract of DOI:10.1007/BF00807432

The three-component reaction of 4-hydroxycoumarin, ethylorthoformiate, and different substituted hydrazines is described. p-Nitrophenylhydrazine, hydrazides and phenylsemicarbazide lead to the expected hydrazinomethylene-chromandiones 2a-f.Reaction of 4-hydroxycoumarin, ethylorthoformiate, and phenylhydrazine or p-tolyl-hydrazine does not yield 2, but the anilino-methylene-chromandiones 6a-b.This indicates a reductive N-N bond cleavage to aniline and ammonia under mild conditions. - Keywords: Hydrazinomethylene-chromandiones; Reductive N-N bond cleavage; Anilinomethylenechromandiones