A Facile Synthesis of gem-Difluorinated Heterocyclic Compounds Using Anodic­ Fluorination of 2-Cyano-1-methylpyrrole as a Key Step

Abstract

Anodic fluorination of 2-cyano-1-methylpyrrole 1 using Et₃N·5HF in an undivided cell provided 5,5-difluoro-1-methyl-3-pyrrolin-2-one (5a). The Diels-Alder reaction of 5a with various dienes was successfully carried out to provide gem-difluorinated heterocyclic compounds in excellent yields.

Key words

anodic fluorination - 5,5-difluoro-1-methyl-3-pyr­roline-2-one - gem-difluoromethylenes - Diels-Alder reaction - dienes

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