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Trialkylborane-Assisted CO(2) Reduction by Late Transition Metal Hydrides.

ABSTRACT: Trialkylborane additives promote reduction of CO(2) to formate by bis(diphosphine) Ni(II) and Rh(III) hydride complexes. The late transition metal hydrides, which can be formed from dihydrogen, transfer hydride to CO(2) to give a formate-borane adduct. The borane must be of appropriate Lewis acidity: weaker acids do not show significant hydride transfer enhancement, while stronger acids abstract hydride without CO(2) reduction. The mechanism likely involves a pre-equilibrium hydride transfer followed by formation of a stabilizing formate-borane adduct.

SUBMITTER: Miller AJ

PROVIDER: S-EPMC3167168 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Trialkylborane-Assisted CO(2) Reduction by Late Transition Metal Hydrides.

Miller Alexander J M AJ Labinger Jay A JA Bercaw John E JE

Organometallics 20110101 16

Trialkylborane additives promote reduction of CO(2) to formate by bis(diphosphine) Ni(II) and Rh(III) hydride complexes. The late transition metal hydrides, which can be formed from dihydrogen, transfer hydride to CO(2) to give a formate-borane adduct. The borane must be of appropriate Lewis acidity: weaker acids do not show significant hydride transfer enhancement, while stronger acids abstract hydride without CO(2) reduction. The mechanism likely involves a pre-equilibrium hydride transfer fol ...[more]

PMID: 21909178

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