Heavy-Metal-Free Reduction Methodology for Large-Scale Synthesis Applicable to Heterocyclic and Arylhydrazines

Abstract

A green chemistry methodology that uses a heavy-metal-free reduction in aqueous medium is described to produce 5-hydrazinoquinoline [1-(quinolin-5-yl)hydrazine] ( 6a ) as the anhydrous dihydrochloride salt at large scale. The process is entirely aqueous and utilizes l -ascorbic acid to reduce the diazonium salt ( 2a ) derived from 5-aminoquinoline [quinolin-5-amine] ( 1a ).