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Catalytic photochemical enantioselective α-alkylation with pyridinium salts.

ABSTRACT: We have developed a chiral amine catalyzed enantioselective α-alkylation of aldehydes with amino acid derived pyridinium salts as alkylating reagents. The reaction proceeds in the presence of visible light and in the absence of a photocatalyst via a light activated charge-transfer complex. We apply this photochemical stereoconvergent process to the total synthesis of the lignan natural products (-)-enterolactone and (-)-enterodiol. Mechanistic studies support the ground-state complexation of the reactive components followed by divergent charge-transfer processes involving catalyst-controlled radical chain and in-cage radical combination steps.

SUBMITTER: Yetra SR

PROVIDER: S-EPMC9847668 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Catalytic photochemical enantioselective α-alkylation with pyridinium salts.

Yetra Santhivardhana Reddy SR Schmitt Nathan N Tambar Uttam K UK

Chemical science 20221208 3

We have developed a chiral amine catalyzed enantioselective α-alkylation of aldehydes with amino acid derived pyridinium salts as alkylating reagents. The reaction proceeds in the presence of visible light and in the absence of a photocatalyst via a light activated charge-transfer complex. We apply this photochemical stereoconvergent process to the total synthesis of the lignan natural products (-)-enterolactone and (-)-enterodiol. Mechanistic studies support the ground-state complexation ...[more]

PMID: 36741522

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