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A Lewis Base Catalysis Approach for the Photoredox Activation of Boronic Acids and Esters.

ABSTRACT: We report herein the use of a dual catalytic system comprising a Lewis base catalyst such as quinuclidin-3-ol or 4-dimethylaminopyridine and a photoredox catalyst to generate carbon radicals from either boronic acids or esters. This system enabled a wide range of alkyl boronic esters and aryl or alkyl boronic acids to react with electron-deficient olefins via radical addition to efficiently form C-C coupled products in a redox-neutral fashion. The Lewis base catalyst was shown to form a redox-active complex with either the boronic esters or the trimeric form of the boronic acids (boroxines) in solution.

SUBMITTER: Lima F

PROVIDER: S-EPMC5708277 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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A Lewis Base Catalysis Approach for the Photoredox Activation of Boronic Acids and Esters.

Lima Fabio F Sharma Upendra K UK Grunenberg Lars L Saha Debasmita D Johannsen Sandra S Sedelmeier Joerg J Van der Eycken Erik V EV Ley Steven V SV

Angewandte Chemie (International ed. in English) 20171024 47

We report herein the use of a dual catalytic system comprising a Lewis base catalyst such as quinuclidin-3-ol or 4-dimethylaminopyridine and a photoredox catalyst to generate carbon radicals from either boronic acids or esters. This system enabled a wide range of alkyl boronic esters and aryl or alkyl boronic acids to react with electron-deficient olefins via radical addition to efficiently form C-C coupled products in a redox-neutral fashion. The Lewis base catalyst was shown to form a redox-ac ...[more]

PMID: 29024307

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