2-PySO₂CF₂H : Bench-stable Difluoromethylating Agent for Catalytic Difluoromethylation

Difluoromethyl 2-pyridyl sulfone (1), which is composed of pyridyl and difluoromethylsulfonyl groups, performs as a difluoromethylating reagent when used with metal catalysts. For example, Hu et al. have reported that 1 reacts with aryl zinc reagents(2) in the presence of tris(2,4-pentanedionato)iron(III) and tetramethylenediamine(TMEDA) giving the corresponding difluoromethylated aryl products in good yields. This reaction can be applied to various aryl group substituted zinc compounds such as a phenyl group and others like methoxy-, trifluoromethyl-, or heteroaryl-substituted aryl groups. In this way, 1 is expected to be used directly as a difluoromethylating reagent introducing a difluoromethyl group into aryl groups.