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Abiotic reduction of ketones with silanes catalysed by carbonic anhydrase through an enzymatic zinc hydride.

ABSTRACT: Enzymatic reactions through mononuclear metal hydrides are unknown in nature, despite the prevalence of such intermediates in the reactions of synthetic transition-metal catalysts. If metalloenzymes could react through abiotic intermediates like these, then the scope of enzyme-catalysed reactions would expand. Here we show that zinc-containing carbonic anhydrase enzymes catalyse hydride transfers from silanes to ketones with high enantioselectivity. We report mechanistic data providing strong evidence that the process involves a mononuclear zinc hydride. This work shows that abiotic silanes can act as reducing equivalents in an enzyme-catalysed process and that monomeric hydrides of electropositive metals, which are typically unstable in protic environments, can be catalytic intermediates in enzymatic processes. Overall, this work bridges a gap between the types of transformation in molecular catalysis and biocatalysis.

SUBMITTER: Ji P

PROVIDER: S-EPMC8675236 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Abiotic reduction of ketones with silanes catalysed by carbonic anhydrase through an enzymatic zinc hydride.

Ji Pengfei P Park Jeeyoung J Gu Yang Y Clark Douglas S DS Hartwig John F JF

Nature chemistry 20210218 4

Enzymatic reactions through mononuclear metal hydrides are unknown in nature, despite the prevalence of such intermediates in the reactions of synthetic transition-metal catalysts. If metalloenzymes could react through abiotic intermediates like these, then the scope of enzyme-catalysed reactions would expand. Here we show that zinc-containing carbonic anhydrase enzymes catalyse hydride transfers from silanes to ketones with high enantioselectivity. We report mechanistic data providing strong ev ...[more]

PMID: 33603222

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