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Rhodium-catalyzed enantioselective silylation of arene C-H bonds: desymmetrization of diarylmethanols.

ABSTRACT: We report a Rh-catalyzed, enantioselective silylation of arene C-H bonds directed by a (hydrido)silyl group. (Hydrido)silyl ethers that are formed in situ by hydrosilylation of benzophenone or its derivatives undergo asymmetric C-H silylation in high yield with excellent enantioselectivity in the presence of [Rh(cod)Cl]2 and a chiral bisphosphine ligand. The stereoselectivity of this process also allows enantioenriched diarylmethanols to react with site selectivity at one aryl group over the other. Enantioenriched benzoxasiloles from the silylation process undergo a range of transformations to form C-C, C-O, C-I, or C-Br bonds.

SUBMITTER: Lee T

PROVIDER: S-EPMC4699421 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Rhodium-catalyzed enantioselective silylation of arene C-H bonds: desymmetrization of diarylmethanols.

Lee Taegyo T Wilson Tyler W TW Berg Robert R Ryberg Per P Hartwig John F JF

Journal of the American Chemical Society 20150520 21

We report a Rh-catalyzed, enantioselective silylation of arene C-H bonds directed by a (hydrido)silyl group. (Hydrido)silyl ethers that are formed in situ by hydrosilylation of benzophenone or its derivatives undergo asymmetric C-H silylation in high yield with excellent enantioselectivity in the presence of [Rh(cod)Cl]2 and a chiral bisphosphine ligand. The stereoselectivity of this process also allows enantioenriched diarylmethanols to react with site selectivity at one aryl group over the oth ...[more]

PMID: 25948056

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