Oxidatively Induced Aryl–CF3 Coupling at Diphosphine Nickel Complexes

This communication describes the synthesis of a series of diphosphine NiII(Ph)(CF3) complexes and studies of their reactivity toward oxidatively induced Ph–CF3 bond-forming reductive elimination. Treatment of these complexes with the one-electron outer-sphere oxidant ferrocenium hexafluorophosphate (FcPF6) affords benzotrifluoride, but the yield varies dramatically as a function of diphosphine ligand. Diphosphines with bite angles of less than 92° afforded <10% yield of PhCF3. In contrast, those with bite angles between 95 and 102° formed PhCF3 in yields ranging from 62 to 77%.