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A Chiral Nitrogen Ligand for Enantioselective, Iridium-Catalyzed Silylation of Aromatic C-H Bonds.

ABSTRACT: Iridium catalysts containing dative nitrogen ligands are highly active for the borylation and silylation of C-H bonds, but chiral analogs of these catalysts for enantioselective silylation reactions have not been developed. We report a new chiral pyridinyloxazoline ligand for enantioselective, intramolecular silylation of symmetrical diarylmethoxy diethylsilanes. Regioselective and enantioselective silylation of unsymmetrical substrates was also achieved in the presence of this newly developed system. Preliminary mechanistic studies imply that C-H bond cleavage is irreversible, but not the rate-determining step.

SUBMITTER: Su B

PROVIDER: S-EPMC5293510 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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A Chiral Nitrogen Ligand for Enantioselective, Iridium-Catalyzed Silylation of Aromatic C-H Bonds.

Su Bo B Zhou Tai-Gang TG Li Xian-Wei XW Shao Xiao-Ru XR Xu Pei-Lin PL Wu Wen-Lian WL Hartwig John F JF Shi Zhang-Jie ZJ

Angewandte Chemie (International ed. in English) 20161215 4

Iridium catalysts containing dative nitrogen ligands are highly active for the borylation and silylation of C-H bonds, but chiral analogs of these catalysts for enantioselective silylation reactions have not been developed. We report a new chiral pyridinyloxazoline ligand for enantioselective, intramolecular silylation of symmetrical diarylmethoxy diethylsilanes. Regioselective and enantioselective silylation of unsymmetrical substrates was also achieved in the presence of this newly developed s ...[more]

PMID: 27976482

Similar Datasets

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