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Enantioselective, organocatalytic reduction of ketones using bifunctional thiourea-amine catalysts.

ABSTRACT: Prochiral ketones are reduced to enantioenriched, secondary alcohols using catecholborane and a family of air-stable, bifunctional thiourea-amine organocatalysts. Asymmetric induction is proposed to arise from the in situ complexation between the borane and chiral thiourea-amine organocatalyst resulting in a stereochemically biased boronate-amine complex. The hydride in the complex is endowed with enhanced nucleophilicity while the thiourea concomitantly embraces and activates the carbonyl.

SUBMITTER: Li de R

PROVIDER: S-EPMC2860298 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Enantioselective, organocatalytic reduction of ketones using bifunctional thiourea-amine catalysts.

Li De Run de R He Anyu A Falck J R JR

Organic letters 20100401 8

Prochiral ketones are reduced to enantioenriched, secondary alcohols using catecholborane and a family of air-stable, bifunctional thiourea-amine organocatalysts. Asymmetric induction is proposed to arise from the in situ complexation between the borane and chiral thiourea-amine organocatalyst resulting in a stereochemically biased boronate-amine complex. The hydride in the complex is endowed with enhanced nucleophilicity while the thiourea concomitantly embraces and activates the carbonyl. ...[more]

PMID: 20334398

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