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Hydroxy-directed iridium-catalyzed enantioselective formal β-C(sp2)–H allylic alkylation of α,β-unsaturated carbonyls† † Electronic supplementary information (ESI) available: Experimental details, characterization and analytical data. See DOI: https://doi.org/10.1039/d2sc03966d

ABSTRACT: Hydroxy-directed iridium-catalyzed enantioselective formal β-C(sp2)–H allylic alkylation of kojic acid and structurally related α,β-unsaturated carbonyl compounds is developed. This reaction, catalyzed by an Ir(i)/(P,olefin) complex, utilizes the nucleophilic character of α-hydroxy α,β-unsaturated carbonyls, to introduce an allyl group at its β-position in a branched-selective manner in good to excellent yield with uniformly high enantioselectivity (up to >99.9 : 0.1 er). To the best of our knowledge, this report represents the first example of the use of kojic acid in a transition metal catalyzed highly enantioselective transformation. The first formal enantioselective β-C(sp2)–H allylic alkylation of α,β-unsaturated carbonyls is developed through hydroxy-directed reaction of α-hydroxy enones with racemic branched allylic alcohols under cooperative Ir(i) and Lewis acid catalysis.

SUBMITTER: Mitra S

PROVIDER: S-EPMC9629034 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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