efficient, regioselectivechlorination of coumarins using Earth-abundant and cost-effective CuCl2 under visible light irradiation is reported. A key feature of this protocol is the photocatalytic dissociation of the copper(II) complex in acetonitrile through ligand-to-metal charge transfer (LMCT) to give the chlorine atom which then selectively chlorinates the coumarin. This method can chlorinate a broad
报道了在可见光照射下使用地球丰富且具有成本效益的 CuCl 2对香豆素进行有效的区域选择性氯化。该协议的一个关键特征是通过配体到金属电荷转移 (LMCT) 将乙腈中的铜 ( II ) 配合物光催化解离,从而产生氯原子,然后选择性地氯化香豆素。该方法可以用吸电子或给电子取代基对范围广泛的香豆素进行氯化,以区域选择性地提供 3-氯香豆素,并以良好至优异的产率进一步扩展到其他缺电子杂环和烯烃,例如黄酮、8-甲氧基补骨脂素和萘醌。