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Silyl Anion Initiated Hydroboration of Aldehydes and Ketones.

ABSTRACT: Hydroboration is an emerging method for mild and selective reduction of carbonyl compounds. Typically, transition-metal or reactive main-group hydride catalysts are used in conjunction with a mild reductant such as pinacolborane. The reactivity of the main-group catalysts is a consequence of the nucleophilicity of their hydride ligands. Silicon hydrides are significantly less reactive and are therefore not efficient hydroboration catalysts. Here, a readily prepared silyl anion is reported to be an effective initiator for the reduction of aldehydes and ketones requiring mild conditions, low catalyst loadings and with a good substrate scope. The silyl anion it is shown to activate HBpin to generate a reactive borohydride in situ which reacts with aldehydes and ketones to afford the hydroboration product.

SUBMITTER: Stanford MW

PROVIDER: S-EPMC7496802 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Silyl Anion Initiated Hydroboration of Aldehydes and Ketones.

Stanford Martin W MW Bismuto Alessandro A Cowley Michael J MJ

Chemistry (Weinheim an der Bergstrasse, Germany) 20200702 44

Hydroboration is an emerging method for mild and selective reduction of carbonyl compounds. Typically, transition-metal or reactive main-group hydride catalysts are used in conjunction with a mild reductant such as pinacolborane. The reactivity of the main-group catalysts is a consequence of the nucleophilicity of their hydride ligands. Silicon hydrides are significantly less reactive and are therefore not efficient hydroboration catalysts. Here, a readily prepared silyl anion is reported to be ...[more]

PMID: 32304609

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