Silicates as Latent Alkyl Radical Precursors: Visible-Light Photocatalytic Oxidation of Hypervalent Bis-Catecholato Silicon Compounds
Silicates as Latent Alkyl Radical Precursors: Visible-Light Photocatalytic Oxidation of Hypervalent Bis-Catecholato Silicon Compounds
复制标题
DOI：
10.1002/anie.201504963
复制
发表时间：
2015-09-21
影响因子：
16.6
通讯作者：
Fensterbank, Louis
中科院分区：
文献类型：
--
作者：
Corce, Vincent;Chamoreau, Lise-Marie;Fensterbank, Louis
本文介绍了超价双邻苯二酚硅化合物作为可见光照射下烷基自由基的多功能来源。以Ir[（dF（CF_3）ppy）（2）（bpy）]-（PF_6）（dF（CF_3）ppy = 2-（2，4-二氟苯基）-5-三氟甲基吡啶，bpy =联吡啶）为光催化氧化剂，可以生成一系列烷基自由基，包括高活性的伯烷基自由基，并参与各种分子间均裂反应。基于循环伏安法，Stern-Volmer的研究，并支持计算，涉及从硅酸盐的光活化铱络合物的单电子转移的机制已被提出。该氧化光催化过程可以有效地与镍催化的C-sp2-C-sp3交叉偶联反应合并。
This works introduces hypervalent bis-catecholato silicon compounds as versatile sources of alkyl radicals upon visible-light photocatalysis. Using Ir[(dF(CF3)ppy)(2)(bpy)]-(PF6) (dF(CF3)ppy = 2-(2,4-difluorophenyl)-5-trifluoromethylpyridine, bpy = bipyridine) as catalytic photooxidant, a series of alkyl radicals, including highly reactive primary ones can be generated and engaged in various intermolecular homolytic reactions. Based on cyclic voltammetry, Stern-Volmer studies, and supported by calculations, a mechanism involving a single-electron transfer from the silicate to the photoactivated iridium complex has been proposed. This oxidative photocatalyzed process can be efficiently merged with nickel-catalyzed C-sp2-C-sp3 cross-coupling reactions.