据报道,一种易于获得的有机-无机杂化催化剂用于α-卤代羰基化合物的还原断裂。稳健的杂化催化剂是 ZnCl 2 Lewis 酸和吖啶橙作为光活性有机染料的自稳定组合。已经使用光物理和电化学实验详细研究了这种混合催化剂的机械特性。一项系统的研究使我们能够发现合适的路易斯酸以有效地稳定α-卤代羰基化合物,从而降低标准有机染料范围内的还原电位。该策略通过引导光氧化还原循环通过氧化猝灭途径解决了脱卤氢化或烷基自由基同源偶联等问题。光活性有机染料和路易斯酸对应物之间的协同作用通过有效和受控地生成烷基自由基,使功能化与广泛的偶联伙伴成为可能,并作为昂贵的后过渡金属基光催化剂的合适替代品。为了证明这种协同催化体系的应用潜力,研究了四种不同的α-羰基溴的合成转化,具有广泛的底物范围。
A visible-light-induced oxidativecoupling of diselenides with readily available vinylarenes is demonstrated. This benign protocol allows one to access a wide range of α-aryl and α-alkyl selenomethyl ketones in good yields with excellent functional group compatibility. The distinct advantages of this protocol over all previous methods include the use of a green solvent and air as an oxidant and the
Preparation of α-Arylseleno-substituted Zinc and Copper Organometallics and their Application in the Synthesis of α-Arylselenomethyl Ketones
作者:Xian Huang、De-Hui Duan
DOI:10.1039/a708947c
日期:——
α-Arylseleno-substituted zinc and copper organometallics, prepared by zinc insertion into the carbon–chlorinebond of α-chloromethyl aryl selenides and with CuCN–2LiCl transmetallation to the corresponding copper reagents, react with acyl chlorides to give α-arylselenomethyl ketones based on the formation of a new carbon–carbon bond.