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Stereoselective synthesis of gamma-substituted (Z)-allylic boranes via kinetically controlled hydroboration of allenes with 10-TMS-9-borabicyclo[3.3.2]decane.

ABSTRACT: Kinetically controlled hydroboration of allenes 8 and 14a-d with the readily accessible Soderquist borane 7, which is generated in situ from borohydride 6, constitutes a convenient and preparatively useful method for synthesis of (Z)-gamma-(substituted)allylboranes 9 and 15a-d. These allylboranes undergo highly diastereo- (> or = 90: 10) and enantioselective (typically 89-96% e.e.) allylboration reactions with representative aldehydes to give syn-beta-functionalized homoallylic alcohols.

SUBMITTER: Kister J

PROVIDER: S-EPMC2767336 | biostudies-other | 2009 Oct

REPOSITORIES: biostudies-other

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Stereoselective synthesis of gamma-substituted (Z)-allylic boranes via kinetically controlled hydroboration of allenes with 10-TMS-9-borabicyclo[3.3.2]decane.

Kister Jeremy J DeBaillie Amy C AC Lira Ricardo R Roush William R WR

Journal of the American Chemical Society 20091001 40

Kinetically controlled hydroboration of allenes 8 and 14a-d with the readily accessible Soderquist borane 7, which is generated in situ from borohydride 6, constitutes a convenient and preparatively useful method for synthesis of (Z)-gamma-(substituted)allylboranes 9 and 15a-d. These allylboranes undergo highly diastereo- (> or = 90: 10) and enantioselective (typically 89-96% e.e.) allylboration reactions with representative aldehydes to give syn-beta-functionalized homoallylic alcohols. ...[more]

PMID: 19775159

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