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Enantioselective, Lewis Base-Catalyzed Carbosulfenylation of Alkenylboronates by 1,2-Boronate Migration.

ABSTRACT: A catalytic, enantioselective method for the preparation of chiral, non-racemic, alkylboronic esters bearing two vicinal stereogenic centers is described. The reaction proceeds via a 1,2-migration of a zwitterionic thiiranium-boronate complex to give exclusively anti carbosulfenylation products. A broad scope of aryl groups migrate with good yield and excellent enantioselectivity (up to 99:1 e.r.). Similarly, a range of di- and trisubstituted alkenylboronic esters are competent reaction partners. This method provides access to both secondary and tertiary chiral alkylboronic esters.

SUBMITTER: Tao Z

PROVIDER: S-EPMC6345169 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Enantioselective, Lewis Base-Catalyzed Carbosulfenylation of Alkenylboronates by 1,2-Boronate Migration.

Tao Zhonglin Z Robb Kevin A KA Panger Jesse L JL Denmark Scott E SE

Journal of the American Chemical Society 20181109 46

A catalytic, enantioselective method for the preparation of chiral, non-racemic, alkylboronic esters bearing two vicinal stereogenic centers is described. The reaction proceeds via a 1,2-migration of a zwitterionic thiiranium-boronate complex to give exclusively anti carbosulfenylation products. A broad scope of aryl groups migrate with good yield and excellent enantioselectivity (up to 99:1 e.r.). Similarly, a range of di- and trisubstituted alkenylboronic esters are competent reaction partners ...[more]

PMID: 30411878

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