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Enantioconvergent iso-Pictet-Spengler Reactions: Organocatalytic Synthesis of Chiral Tetrahydro-γ-carbolines.

ABSTRACT: Enantioconvergent iso-Pictet-Spengler reactions of chiral racemic ß-formyl esters and a ß-keto ester are reported, providing complex tetrahydro-γ-carbolines containing two contiguous stereocenters. The reactions are catalyzed by a chiral thiourea and benzoic acid cocatalytic system and constitute rare cases of nonhydrogenative stereoconvergent additions to racemic α-stereogenic-ß-dicarbonyls. Elaboration of the products to chiral aminoalcohols and carbamates is demonstrated.

SUBMITTER: Cassels WR

PROVIDER: S-EPMC10529283 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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Enantioconvergent iso-Pictet-Spengler Reactions: Organocatalytic Synthesis of Chiral Tetrahydro-γ-carbolines.

Cassels William R WR Fulton Jennifer L JL Johnson Jeffrey S JS

Organic letters 20230706 28

Enantioconvergent iso-Pictet-Spengler reactions of chiral racemic ß-formyl esters and a ß-keto ester are reported, providing complex tetrahydro-γ-carbolines containing two contiguous stereocenters. The reactions are catalyzed by a chiral thiourea and benzoic acid cocatalytic system and constitute rare cases of nonhydrogenative stereoconvergent additions to racemic α-stereogenic-ß-dicarbonyls. Elaboration of the products to chiral aminoalcohols and carbamates is demonstrated. ...[more]

PMID: 37410881

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