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Selective synthesis of functionalized, tertiary silanes by diastereoselective rearrangement-addition.

ABSTRACT: [reaction: see text] Treatment of hydroxy-substituted silyl epoxides with Grignard reagents induces a 1,2-carbon shift to reveal alpha-silyl aldehydes, which are trapped by highly diastereoselective addition reactions of the Grignard reagent. The starting epoxides are readily accessible from propargylic alcohols by regio- and diastereoselective hydrosilylation and epoxidation reactions. In addition to providing functionalized tertiary silane products, the method is shown to offer a tertiary olefin synthesis through chemo- and diastereoselective Peterson elimination of the product tertiary silane diols.

SUBMITTER: Trost BM

PROVIDER: S-EPMC2509579 | biostudies-literature | 2005 Oct

REPOSITORIES: biostudies-literature

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Selective synthesis of functionalized, tertiary silanes by diastereoselective rearrangement-addition.

Trost Barry M BM Ball Zachary T ZT Kang Eun-Joo EJ

Organic letters 20051001 22

[reaction: see text] Treatment of hydroxy-substituted silyl epoxides with Grignard reagents induces a 1,2-carbon shift to reveal alpha-silyl aldehydes, which are trapped by highly diastereoselective addition reactions of the Grignard reagent. The starting epoxides are readily accessible from propargylic alcohols by regio- and diastereoselective hydrosilylation and epoxidation reactions. In addition to providing functionalized tertiary silane products, the method is shown to offer a tertiary olef ...[more]

PMID: 16235920

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