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Intramolecular photochemical [2 + 1]-cycloadditions of nucleophilic siloxy carbenes.

ABSTRACT: Visible light induced singlet nucleophilic carbenes undergo rapid [2 + 1]-cycloaddition with tethered olefins to afford unique bicyclo[3.1.0]hexane and bicyclo[4.1.0]heptane scaffolds. This cyclopropanation process requires only visible light irradiation to proceed, circumventing the use of exogenous (photo)catalysts, sensitisers or additives and showcases a vastly underexplored mode of reactivity for nucleophilic carbenes in chemical synthesis. The discovery of additional transformations including a cyclopropanation/retro-Michael/Michael cascade process to afford chromanones and a photochemical C-H insertion reaction are also described.

SUBMITTER: Bunyamin A

PROVIDER: S-EPMC8926286 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Intramolecular photochemical [2 + 1]-cycloadditions of nucleophilic siloxy carbenes.

Bunyamin Amanda A Hua Carol C Polyzos Anastasios A Priebbenow Daniel L DL

Chemical science 20220225 11

Visible light induced singlet nucleophilic carbenes undergo rapid [2 + 1]-cycloaddition with tethered olefins to afford unique bicyclo[3.1.0]hexane and bicyclo[4.1.0]heptane scaffolds. This cyclopropanation process requires only visible light irradiation to proceed, circumventing the use of exogenous (photo)catalysts, sensitisers or additives and showcases a vastly underexplored mode of reactivity for nucleophilic carbenes in chemical synthesis. The discovery of additional transformations includ ...[more]

PMID: 35414869

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