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C-H Bond Activation by an Imido Cobalt(III) and the Resulting Amido Cobalt(II) Complex.

ABSTRACT: The 3d-metal mediated nitrene transfer is under intense scrutiny due to its potential as an atom economic and ecologically benign way for the directed amination of (un)functionalised C-H bonds. Here we present the isolation and characterisation of a rare, trigonal imido cobalt(III) complex, which bears a rather long cobalt-imido bond. It can cleanly cleave strong C-H bonds with a bond dissociation energy of up to 92?kcal?mol-1 in an intermolecular fashion, unprecedented for imido cobalt complexes. This resulted in the amido cobalt(II) complex [Co(hmds)2 (NHt Bu)]- . Kinetic studies on this reaction revealed an H atom transfer mechanism. Remarkably, the cobalt(II) amide itself is capable of mediating H atom abstraction or stepwise proton/electron transfer depending on the substrate. A cobalt-mediated catalytic application for substrate dehydrogenation using an organo azide is presented.

SUBMITTER: Reckziegel A

PROVIDER: S-EPMC7318117 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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C-H Bond Activation by an Imido Cobalt(III) and the Resulting Amido Cobalt(II) Complex.

Reckziegel Alexander A Pietzonka Clemens C Kraus Florian F Werncke C Gunnar CG

Angewandte Chemie (International ed. in English) 20200327 22

The 3d-metal mediated nitrene transfer is under intense scrutiny due to its potential as an atom economic and ecologically benign way for the directed amination of (un)functionalised C-H bonds. Here we present the isolation and characterisation of a rare, trigonal imido cobalt(III) complex, which bears a rather long cobalt-imido bond. It can cleanly cleave strong C-H bonds with a bond dissociation energy of up to 92 kcal mol<sup>-1</sup> in an intermolecular fashion, unprecedented for imido coba ...[more]

PMID: 32119164

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