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Traceless Silylation of ?-C(sp3)-H Bonds of Alcohols via Perfluorinated Acetals.

ABSTRACT: We report the silylation of primary C-H bonds located ? to secondary and tertiary alcohols by exploiting perfluorinated esters as traceless directing groups. The conversion of a secondary or tertiary alcohol to a perfluoroalkyl ester and conversion of the ester to the corresponding silyl acetals by hydrosilylation allows for selective ?-C(sp3)-H silylation catalyzed by the combination of [Ir(cod)OMe]2 and Me4Phen (3,4,7,8-tetramethyl-1,10-phenanthroline) to form 6-membered dioxasilinane. Tamao-Fleming oxidation of these dioxasilinane leads to 1,2 diols. The developed sequence was applied to a series of natural products containing hydroxyl groups.

SUBMITTER: Bunescu A

PROVIDER: S-EPMC5809123 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Traceless Silylation of β-C(sp3)-H Bonds of Alcohols via Perfluorinated Acetals.

Bunescu Ala A Butcher Trevor W TW Hartwig John F JF

Journal of the American Chemical Society 20180119 4

We report the silylation of primary C-H bonds located β to secondary and tertiary alcohols by exploiting perfluorinated esters as traceless directing groups. The conversion of a secondary or tertiary alcohol to a perfluoroalkyl ester and conversion of the ester to the corresponding silyl acetals by hydrosilylation allows for selective β-C(sp3)-H silylation catalyzed by the combination of [Ir(cod)OMe]2 and Me4Phen (3,4,7,8-tetramethyl-1,10-phenanthroline) to form ...[more]

PMID: 29283571

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