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A Borane Lewis Acid in the Secondary Coordination Sphere of a Ni(II) Imido Imparts Distinct C-H Activation Selectivity.

ABSTRACT: Two borane-functionalized bidentate phosphine ligands that vary in tether length have been prepared to examine cooperative metal-substrate interactions. Ni(0) complexes react with aryl azides at low temperatures to form structurally unusual κ²-(N,N)-N₃Ar adducts. Warming these adducts affords products of N₂ extrusion and in one case, a Ni-imido compound that is capped by the appended borane. Reactions with 1-azidoadamantane (AdN₃) provide a distinct outcome, where a proposed nickel imido intermediate activates the sp² C-H bonds of arenes, even in the presence of benzylic C-H sites. Combined experimental and computational mechanistic studies demonstrate that the unique reactivity is a consequence of Lewis-acid-induced polarization of the Ni-NR bond, potentially providing a synthetic strategy for chemoselective reaction engineering.

SUBMITTER: Wang B

PROVIDER: S-EPMC10276360 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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A Borane Lewis Acid in the Secondary Coordination Sphere of a Ni(II) Imido Imparts Distinct C-H Activation Selectivity.

Wang Baolu B Seo Chris S G CSG Zhang Cuijuan C Chu Jiaxiang J Szymczak Nathaniel K NK

Journal of the American Chemical Society 20220816 34

Two borane-functionalized bidentate phosphine ligands that vary in tether length have been prepared to examine cooperative metal-substrate interactions. Ni(0) complexes react with aryl azides at low temperatures to form structurally unusual κ2-(N,N)-N3Ar adducts. Warming these adducts affords products of N2 extrusion and in one case, a Ni-imido compound that is capped by the appended borane. Reactions with 1-azidoadamantane (AdN3) provide a dist ...[more]

PMID: 35973127

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