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Enantioselective Synthesis of ?-Lactams by Lewis Base Catalyzed Sulfenoamidation of Alkenes.

ABSTRACT: A method for the catalytic, enantioselective, intramolecular 1,2-sulfenoamidation of alkenes is described. Lewis base activation of a suitable sulfur electrophile generates an enantioenriched, thiiranium ion intermediate from a ?,?-unsaturated sulfonyl carboxamide. This intermediate is subsequently intercepted by the sulfonamide nitrogen resulting in cyclization to form ?-lactams. Electron-poor alkenes required the use of a new selenophosphoramidate Lewis base catalyst. Subsequent manipulations of the products harness the latent reactivity of both the amide and thioether functionality.

SUBMITTER: Panger JL

PROVIDER: S-EPMC7127933 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Enantioselective Synthesis of γ-Lactams by Lewis Base Catalyzed Sulfenoamidation of Alkenes.

Panger Jesse L JL Denmark Scott E SE

Organic letters 20191220 7

A method for the catalytic, enantioselective, intramolecular 1,2-sulfenoamidation of alkenes is described. Lewis base activation of a suitable sulfur electrophile generates an enantioenriched, thiiranium ion intermediate from a β,γ-unsaturated sulfonyl carboxamide. This intermediate is subsequently intercepted by the sulfonamide nitrogen resulting in cyclization to form γ-lactams. Electron-poor alkenes required the use of a new selenophosphoramidate Lewis base catalyst. Subsequent manipulations ...[more]

PMID: 31858805

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