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A Redox-Active Nickel Complex that Acts as an Electron Mediator in Photochemical Giese Reactions.

ABSTRACT: We report a simple protocol for the photochemical Giese addition of C(sp³ )-centered radicals to a variety of electron-poor olefins. The chemistry does not require external photoredox catalysts. Instead, it harnesses the excited-state reactivity of 4-alkyl-1,4-dihydropyridines (4-alkyl-DHPs) to generate alkyl radicals. Crucial for reactivity is the use of a catalytic amount of Ni(bpy)₃ ²⁺ (bpy=2,2'-bipyridyl), which acts as an electron mediator to facilitate the redox processes involving fleeting and highly reactive intermediates.

SUBMITTER: van Leeuwen T

PROVIDER: S-EPMC6519288 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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A Redox-Active Nickel Complex that Acts as an Electron Mediator in Photochemical Giese Reactions.

van Leeuwen Thomas T Buzzetti Luca L Perego Luca Alessandro LA Melchiorre Paolo P

Angewandte Chemie (International ed. in English) 20190306 15

We report a simple protocol for the photochemical Giese addition of C(sp3 )-centered radicals to a variety of electron-poor olefins. The chemistry does not require external photoredox catalysts. Instead, it harnesses the excited-state reactivity of 4-alkyl-1,4-dihydropyridines (4-alkyl-DHPs) to generate alkyl radicals. Crucial for reactivity is the use of a catalytic amount of Ni(bpy)3 2+ (bpy=2,2'-bipyridyl), which acts as an electron mediator to facilitate the ...[more]

PMID: 30747467

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