Reaction of difluorocarbene with anions from amides and oximes: Synthesis of N-difluoromethyl substituted amides, O-difluoromethylimidates or O-difluoromethyl substituted oximes under phase-transfer catalysis conditions

N-Aryl substituted amides react with chlorodifluoromethane in the presence of concentrated aqueous sodium hydroxide and benzyltriethylammonium chloride (TEBAC) as a catalyst in benzene (phase-transfer catalysis, PTC), affording mixtures of N- and O-difluoromethyl substituted derivatives. Amide anions are involved in this process. The reaction carried out with oximes gives O-difluoromethyl oxime ethers.

Graphical abstractN-Aryl amides react with chlorodifluoromethane under PTC conditions affording N- and O-difluoromethyl substituted products. PTC reation of oximes with thus haloform gives only O-difluoromethyl derivatives. Figure optionsDownload full-size imageDownload as PowerPoint slide