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α-Silicon effect assisted Curtin-Hammett allylation using allylcopper reagents derived from 1,3-dienylsilanes.

ABSTRACT: Cu-catalyzed stereoselective synthesis of (E)-δ-silyl-anti-homoallylic alcohols from 1,3-dienylsilane was developed. Mechanistic studies revealed that the borocupration of dienylsilane proceeded through a 1,2-addition pathway to give an allylcopper intermediate with Cu distal to the silyl group. However, the subsequent aldehyde allylation proceeded via Curtin-Hammett control to give (E)-δ-silyl-anti-homoallylic alcohols with high diastereoselectivities. This method was applied to the synthesis of the C1-9 fragment of a polyketide natural product, mycinolide IV.

SUBMITTER: Gao S

PROVIDER: S-EPMC6713862 | biostudies-other | 2019 Aug

REPOSITORIES: biostudies-other

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α-Silicon effect assisted Curtin-Hammett allylation using allylcopper reagents derived from 1,3-dienylsilanes.

Gao Shang S Chen Ming M

Chemical science 20190628 32

Cu-catalyzed stereoselective synthesis of (E)-δ-silyl-anti-homoallylic alcohols from 1,3-dienylsilane was developed. Mechanistic studies revealed that the borocupration of dienylsilane proceeded through a 1,2-addition pathway to give an allylcopper intermediate with Cu distal to the silyl group. However, the subsequent aldehyde allylation proceeded via Curtin-Hammett control to give (E)-δ-silyl-anti-homoallylic alcohols with high diastereoselectivities. This me ...[more]

PMID: 31489170

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