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Transition-Metal-Free Cleavage of CO.

ABSTRACT: Tertiary silane 1^H , 2-[(diphenylsilyl)methyl]-6-methylpyridine, reacts with tris(pentafluorophenyl)borane (BCF) to form the intramolecular pyridine-stabilized silylium 1⁺ -HBCF. The corresponding 2-[(diphenylsilyl)methyl]pyridine, lacking the methyl-group on the pyridine ring, forms classic N(py)→B adduct 2^H -BCF featuring an intact silane Si-H fragment. Complex 1⁺ -HBCF promotes cleavage of the C≡O triple bond in carbon monoxide with double C-C_sp2 bond formation, leading to complex 3 featuring a B-(diarylmethyl)-B-aryl-boryloxysilane fragment. Reaction with pinacol generates bis(pentafluorophenyl)methane 4 as isolable product, proving the transition-metal-free deoxygenation of carbon monoxide by this main-group system. Experimental data and DFT calculations support the existence of an equilibrium between the silylium-hydroborate ion pair and the silane-borane mixture that is responsible for the observed reactivity.

SUBMITTER: Devillard M

PROVIDER: S-EPMC5656908 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Transition-Metal-Free Cleavage of CO.

Devillard Marc M de Bruin Bas B Siegler Maxime A MA van der Vlugt J I JI

Chemistry (Weinheim an der Bergstrasse, Germany) 20170907 55

Tertiary silane 1H , 2-[(diphenylsilyl)methyl]-6-methylpyridine, reacts with tris(pentafluorophenyl)borane (BCF) to form the intramolecular pyridine-stabilized silylium 1+ -HBCF. The corresponding 2-[(diphenylsilyl)methyl]pyridine, lacking the methyl-group on the pyridine ring, forms classic N(py)→B adduct 2H -BCF featuring an intact silane Si-H fragment. Complex 1+ -HBCF promotes cleavage of the C≡O triple bond in carbon monoxide with double C-Cs ...[more]

PMID: 28816371

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