Difluoromethylated Difunctionalization of Alkenes under Visible Light.

Difluoromethylated compounds usually act as bioisosteres for alcohol functional groups and show unique physicochemical and biological properties. The cyano-difluoromethylation of alkenes using 5-((difluoromethyl)sulfonyl)-1-phenyl-1-tetrazole as a CFH radical difluoromethyl precursor was developed to afford nitriles including a CFH group. A low-cost, stable, easily handled 5-((difluoromethyl)sulfonyl)-1-methyl--tetrazole (DFSMT) was synthesized and applied as the radical CFH reagent. Using DFSMT as the radical CFH precursor, the oxyl-difluoromethylation of alkenes was developed to obtain difluoromethylated ether products. All of the reactions showed good functional group tolerability. Initial mechanistic experiments indicated that the CFH radical was involved as the key active intermediate.