σ-Noninnocence: Masked Phenyl-Cation Transfer at Formal Ni^IV.

ABSTRACT: Reductive elimination is an elementary organometallic reaction step involving a formal oxidation state change of -2 at a transition-metal center. For a series of formal high-valent Ni^IV complexes, aryl-CF₃ bond-forming reductive elimination was reported to occur readily (Bour et al. J. Am. Chem. Soc. 2015, 137, 8034-8037). We report a computational analysis of this reaction and find that, unexpectedly, the formal Ni^IV centers are better described as approaching a +II oxidation state, originating from highly covalent metal-ligand bonds, a phenomenon attributable to σ-noninnocence. A direct consequence is that the elimination of aryl-CF₃ products occurs in an essentially redox-neutral fashion, as opposed to a reductive elimination. This is supporte

SUBMITTER: Steen JS 

PROVIDER: S-EPMC6771483 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature