Cobalt‐catalyzed Selective CF Bond Activation and Alkylation of Polyfluoroaryl Imines

Abstract

AbstractIn this paper the CF bond activation of polyfluoroaryl imines is explored at cobalt(0) center with an imine‐N atom as an anchoring group. The reaction of F5C6‐CHN‐(2′‐ClC6H4) (2) and F5C6‐CHN‐C6H5 (3) with Co(PMe3)4 afforded the CF bond activation products (ortho‐F4C6‐CHN‐(2′‐ClC6H4))Co(I)(PMe3)3 (5) and (ortho‐F4C6‐CHN‐C6H5)Co(II)(F)(PMe3)2 (6), while only π‐(CN) coordinated cobalt(0) complex (2,4,5‐F3C6H2‐CHN‐(4′‐ClC6H4))Co(0)(PMe3)3 (4) was obtained from 2,4,5‐F3C6H2‐CHN‐(4′‐ClC6H4) (1) without CF bond activation. Complexes 4–6 were characterized through X‐ray single crystal diffraction. It was also found that dialkylation of N‐(perfluorobenzylidene)benzenamine with organozinc reagents could be catalyzed by Co(PMe3)4 via C,C‐coupling reaction under mild conditions.