We report a simple protocol for the photochemical Giese addition of C(sp )-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) (bpy=2,2'-bipyridyl), which acts as an electron mediator to facilitate the redox processes involving fleeting and highly reactive intermediates.
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| http://dx.doi.org/10.1002/anie.201814497 | DOI Listing |
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