Electrosynthesis of Oxazol-2(3H)-Ones and Diaroylhydrazines from 1,2-Dicarbonyl Compounds and Arenediazonium Salts

Abstract:

New five-membered oxazol-2(3H)-one heterocycles and 1,2-diaroylhydrazines are obtained in good yield when 1,2-dicarbonyl substrates are reduced at the cathode in N-methyl formamide/LiClO4 as solvent-supporting-electrolyte system, and in the presence of arenediazonium salts. Electrochemical pathways are presented to involve a) cascade reactions: hydrogen atom abstraction from a solvent molecule, radical coupling reaction with substrate intermediate, and intramolecular migration of a methylamino group, to provide oxazolones or b) surprising C−C bond cleavage in the substrate radical anion, assisted by a diazonium salt, that evolves to disubstituted arylhydrazides.

Año de publicación:

2019

Keywords:

• 3-methyl-oxazol-2(3H)-ones
• 1,2-diaroylhydrazines
• electrochemical reduction
• N-methylformamide
• radical coupling

Fuente:

scopus