N,N'-Difluoro-2,2'-bipyridinium Bis(tetrafluoroborate): a New Terminal Oxidant for Iodoarene-catalyzed Fluorination Reactions

A new N-F reagent, N,N'-difluoro-2,2';-bipyridinium bis(tetrafluoroborate), for iodoarene-catalyzed fluorination reactions as a terminal oxidant is reported. This reaction is effective for the fluorination of simple alkenes, aromatic alkenes and 1,3-dicarbonyl compounds, giving 1,2-difluorinated alkanes, geminal difluorinated compounds, 2-fluorinated-1,3-dicarbonyl compounds in good to high yields, respectively. This is a useful fluorination reaction that not only improves the issues of the fluorination reaction using conventional mCPBA as a terminal oxidant but also constructs a simpler catalytic cycle. The present N-F reagent can be recovered as 2,2'-bipyridine.