一种在光化学吉泽反应中充当电子媒介体的氧化还原活性镍配合物。

van Leeuwen Thomas, Buzzetti Luca, Perego Luca Alessandro, Melchiorre Paolo

ICIQ-Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology, Avenida Països Catalans 16, 43007, Tarragona, Spain.

IIT-Istituto Italiano di Tecnologia, Laboratory of Asymmetric Catalysis and Photochemistry, via Morego 30, 16163, Genoa, Italy.

Angew Chem Int Ed Engl. 2019 Apr 1;58(15):4953-4957. doi: 10.1002/anie.201814497. Epub 2019 Mar 6.

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.

我们报道了一种将以C(sp³)为中心的自由基光化学加成到各种缺电子烯烃上的简单方法。该反应不需要外部光氧化还原催化剂。相反，它利用4-烷基-1,4-二氢吡啶（4-烷基-DHPs）的激发态反应性来生成烷基自由基。反应活性的关键在于使用催化量的Ni(bpy)₃（bpy = 2,2'-联吡啶），它作为电子介质促进涉及瞬态且高反应性中间体的氧化还原过程。