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Chiral Lewis Base-Catalysed Asymmetric Syntheses of Benzo-fused ϵ-Lactones.

ABSTRACT: We herein report a two-step protocol for the asymmetric synthesis of novel chiral benzofused ϵ-lactones starting from O-protected hydroxymethyl-para-quinone methides and activated aryl esters. By using chiral isothiourea Lewis base catalysts a broad variety of differently substituted products could be obtained in yields of around 50 % over both steps with high levels of enantioselectivities, albeit low diastereoselectivities only.

SUBMITTER: Stockhammer L

PROVIDER: S-EPMC11005097 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Chiral Lewis Base-Catalysed Asymmetric Syntheses of Benzo-fused ϵ-Lactones.

Stockhammer Lotte L Radetzky Maximilian M Khatoon Syeda Sadia SS Bechmann Matthias M Waser Mario M

European journal of organic chemistry 20230918 39

We herein report a two-step protocol for the asymmetric synthesis of novel chiral benzofused ϵ-lactones starting from O-protected hydroxymethyl-para-quinone methides and activated aryl esters. By using chiral isothiourea Lewis base catalysts a broad variety of differently substituted products could be obtained in yields of around 50 % over both steps with high levels of enantioselectivities, albeit low diastereoselectivities only. ...[more]

PMID: 38601860

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