The oxidative coupling of sp3 hybridized carbon atoms by photocatalysis is a valuable synthetic method as stoichiometric oxidation reagents can be avoided and dihydrogen is the only byproduct of the reaction. Cadmium sulfide, a readily available semiconductor, was used as a visible light heterogeneous photocatalyst for the oxidative coupling of benzyl alcohols and benzyl amines by irradiation with blue light. Depending on the structure of the starting material, good to excellent yields of homocoupling products were obtained as mixtures of diastereomers. Cross-coupling between benzyl alcohols and benzyl amines gave product mixtures, but was selective for the coupling of tetrahydroisoquinolines to nitromethane. The results demonstrate that CdS is a suitable visible light photocatalyst for oxidative bond formation under anaerobic conditions.
通过光催化对sp3杂化碳原子的氧化耦合是一种有价值的合成方法,因为可以避免使用
化学计量的氧化试剂,并且反应中唯一的副产物是
氢气。使用易得的半导体
硫化
镉作为可见光异相光催化剂,通过蓝光照射对
苄醇和
苄胺进行氧化耦合。根据起始材料的结构,获得了良好至优异的同耦合产物产率,并且这些产物是消旋异构体的混合物。
苄醇和
苄胺之间的交叉耦合产生了产物混合物,但对
四氢异喹啉与亚
硝基甲烷的耦合具有选择性。结果表明,
硫化
镉是适合在厌氧条件下进行氧化键形成的可见光光催化剂。