Photochemical generation of radicals is a powerful way to construct various molecules. But most of these methods rely on initiators or the redox properties of radical precursors. Herein, we report a photochemical organic catalyst that reacts with benzyl halide to generate carbon radical via an SN2 pathway. This nucleophilic catalyst can be easily prepared and is bench-stable. The SN2 process does not
光化学产生自由基是构建各种分子的有效方法。但这些方法大多数依赖于引发剂或自由基前体的氧化还原特性。在此,我们报道了一种光化学有机催化剂,它与卤化苄反应,通过 S N 2 途径产生碳自由基。这种亲核催化剂易于制备并且工作台稳定。 S N 2 工艺不依赖于卤化物的氧化还原特性,显示出潜在的合成效用。对照实验和紫外可见光谱分析表明S N 2 取代加合物是关键中间体。
Benzyl radical addition reaction through the homolytic cleavage of a benzylic C–H bond
Direct generation of a benzyl radical by C–H bond activation of toluenes and the addition reaction of the resulting radical to an electron deficient olefin were developed. The reaction of dimethyl fumarate with toluene in the presence of Et3B as a radical initiator at reflux afforded 2-benzylsuccinic acid dimethyl ester in good yield.