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Synthesis of Chiral Bifunctional NHC Ligands and Survey of Their Utilities in Asymmetric Gold Catalysis.

ABSTRACT: The synthesis and characterization of the chiral bifunctional NHC ligands based on the imidazo[1,5-a]pyridine (ImPy) scaffold are described. These ligands possess a fluxional biaryl axis and a chiral center. The configurational stability of the biaryl axis in their gold(I) complexes is investigated. The application of these axially chiral ImPy-based AuCl complexes in a series of gold catalysis is explored, and varying degrees of asymmetric induction are observed. In most cases, the ligand (aS,R)-L8-H with its cyclohexyl group pointing to the reaction site and hence exerting asymmetric steric influence is more effective in asymmetric induction.

SUBMITTER: Zhang JQ

PROVIDER: S-EPMC8290929 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Synthesis of Chiral Bifunctional NHC Ligands and Survey of Their Utilities in Asymmetric Gold Catalysis.

Zhang Jun-Qi JQ Liu Yunkui Y Wang Xing-Wang XW Zhang Liming L

Organometallics 20190801 20

The synthesis and characterization of the chiral bifunctional NHC ligands based on the imidazo[1,5-<i>a</i>]pyridine (ImPy) scaffold are described. These ligands possess a fluxional biaryl axis and a chiral center. The configurational stability of the biaryl axis in their gold(I) complexes is investigated. The application of these axially chiral ImPy-based AuCl complexes in a series of gold catalysis is explored, and varying degrees of asymmetric induction are observed. In most cases, the ligand ...[more]

PMID: 34290468

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