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Catalytic Asymmetric C-H Arylation of (?6-Arene)Chromium Complexes: Facile Access to Planar-Chiral Phosphines.

ABSTRACT: A catalytic asymmetric direct C-H arylation of (?6-arene)chromium complexes to obtain planar-chiral compounds is reported. The use of the hemilabile ligand H8-BINAP(O) is key to providing high enantioselectivity in this transformation. We show that this methodology opens the door to the synthesis of a variety of planar-chiral chromium derivatives which can be easily transformed into planar chiral mono- or diphosphines. Mechanistic studies, including synthesis and characterization of Pd and Ag complexes and their detection in the reaction mixture, suggest a Pd-catalyzed/Ag-promoted catalytic system where Ag carries out the C-H activation step.

SUBMITTER: Batuecas M

PROVIDER: S-EPMC7011738 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Catalytic Asymmetric C-H Arylation of (η6-Arene)Chromium Complexes: Facile Access to Planar-Chiral Phosphines.

Batuecas María M Luo Junfei J Gergelitsová Ivana I Krämer Katrina K Whitaker Daniel D Vitorica-Yrezabal Iñigo J IJ Larrosa Igor I

ACS catalysis 20190425 6

A catalytic asymmetric direct C-H arylation of (η6-arene)chromium complexes to obtain planar-chiral compounds is reported. The use of the hemilabile ligand H8-BINAP(O) is key to providing high enantioselectivity in this transformation. We show that this methodology opens the door to the synthesis of a variety of planar-chiral chromium derivatives which can be easily transformed into planar chiral mono- or diphosphines. Mechanistic studies, including synthesis and characteri ...[more]

PMID: 32064145

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