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Enantioselective photoredox dehalogenative protonation.

ABSTRACT: We report an enantioselective photoredox dehalogenative protonation as a new type of asymmetric protonation. As a paradigm, with a cooperative catalytic system consisting of a chiral H-bonding catalyst and a dicyanopyrazine-derived chromophore (DPZ) photosensitizer that is irradiated with visible light, a range of cyclic and acyclic ketones with labile chiral secondary C-F, C-Cl and C-Br bonds at the ?-position were obtained in high yields with good to excellent enantioselectivities (up to >99% ee) by using a secondary amine as the terminal reductant. Given the ready accessibility of halides, the success of this work should provide inspiration for constructing diverse chiral ?-tertiary carbonyls and their variants.

SUBMITTER: Hou M

PROVIDER: S-EPMC6625487 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Enantioselective photoredox dehalogenative protonation.

Hou Meimei M Lin Lu L Chai Xiangpei X Zhao Xiaowei X Qiao Baokun B Jiang Zhiyong Z

Chemical science 20190607 27

We report an enantioselective photoredox dehalogenative protonation as a new type of asymmetric protonation. As a paradigm, with a cooperative catalytic system consisting of a chiral H-bonding catalyst and a dicyanopyrazine-derived chromophore (DPZ) photosensitizer that is irradiated with visible light, a range of cyclic and acyclic ketones with labile chiral secondary C-F, C-Cl and C-Br bonds at the α-position were obtained in high yields with good to excellent enantioselectivities (up to >99% ...[more]

PMID: 31367315

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