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Dual Nickel- and Photoredox-Catalyzed Enantioselective Desymmetrization of Cyclic meso-Anhydrides.

ABSTRACT: The enantioselective desymmetrization of cyclic meso-anhydrides with benzyl trifluoroborates under nickel-photoredox catalysis is described. The reaction tolerates a variety of sterically and electronically different trifluoroborates, as well as structurally unique cyclic anhydrides. The trans isomer of the keto-acid products is also observed at varying levels dependent on the trifluoroborate identity and relative catalyst loading. A mechanism involving decarbonylation and Ni-C bond homolysis of a NiII adduct is proposed. This feature allows access to a trans keto-acid as the major product in high enantioselectivity from a cis meso anhydride.

SUBMITTER: Stache EE

PROVIDER: S-EPMC5510164 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Dual Nickel- and Photoredox-Catalyzed Enantioselective Desymmetrization of Cyclic meso-Anhydrides.

Stache Erin E EE Rovis Tomislav T Doyle Abigail G AG

Angewandte Chemie (International ed. in English) 20170223 13

The enantioselective desymmetrization of cyclic meso-anhydrides with benzyl trifluoroborates under nickel-photoredox catalysis is described. The reaction tolerates a variety of sterically and electronically different trifluoroborates, as well as structurally unique cyclic anhydrides. The trans isomer of the keto-acid products is also observed at varying levels dependent on the trifluoroborate identity and relative catalyst loading. A mechanism involving decarbonylation and Ni-C bond homolysis of ...[more]

PMID: 28230304

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