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Catalytic asymmetric allylation of aldehydes with alkenes through allylic C(sp³)-H functionalization mediated by organophotoredox and chiral chromium hybrid catalysis.

ABSTRACT: We describe a hybrid system that realizes cooperativity between an organophotoredox acridinium catalyst and a chiral chromium complex catalyst, thereby enabling unprecedented exploitation of unactivated hydrocarbon alkenes as precursors to chiral allylchromium nucleophiles for asymmetric allylation of aldehydes. The reaction proceeds under visible light irradiation at room temperature, affording the corresponding homoallylic alcohols with a diastereomeric ratio >20/1 and up to 99% ee. The addition of Mg(ClO₄)₂ markedly enhanced both the reactivity and enantioselectivity.

SUBMITTER: Mitsunuma H

PROVIDER: S-EPMC6430092 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Catalytic asymmetric allylation of aldehydes with alkenes through allylic C(sp3)-H functionalization mediated by organophotoredox and chiral chromium hybrid catalysis.

Mitsunuma Harunobu H Tanabe Shun S Fuse Hiromu H Ohkubo Kei K Kanai Motomu M

Chemical science 20190117 12

We describe a hybrid system that realizes cooperativity between an organophotoredox acridinium catalyst and a chiral chromium complex catalyst, thereby enabling unprecedented exploitation of unactivated hydrocarbon alkenes as precursors to chiral allylchromium nucleophiles for asymmetric allylation of aldehydes. The reaction proceeds under visible light irradiation at room temperature, affording the corresponding homoallylic alcohols with a diastereomeric ratio >20/1 and up to 99% ee. The additi ...[more]

PMID: 30996935

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