CuMgAl hydrotalcite as an efficient bifunctional catalyst for the cross-dehydrogenative C–C coupling reactions under mild conditions
作者:Weiyou Zhou、Wangmingzhu Lu、Hui Wang、Zhenzhen Xia、Shaoyan Zhai、Zhong Zhang、Yuanjun Ma、Mingyang He、Qun Chen
DOI:10.1016/j.apcata.2020.117771
日期:2020.8
the aerobic CDC reactions. The results indicated that NH3·H2O coprecipitated CuMgAl LDH (N-CuMgAl-LDH) was able to efficiently accelerate the CDC reactions between the α-Csp3–H of N-aryltetrahydroisoquinolines and nucleophiles. A wide scope of N-aryltetrahydroisoquinoline analogues and nucleophiles with different CH bonds (Csp3–H, Csp2–H and Csp–H) could be tolerated by the N-CuMgAl-LDH system. Compared
合成了CuMgAl层状双氢氧化物(CuMgAl-LDHs),并在好氧CDC反应中进行了表征和研究。结果表明,NH 3 ·H 2 O共沉淀的CuMgAl LDH(N-CuMgAl-LDH)能够有效地促进N-芳基四氢异喹啉的α- C sp3- H与亲核试剂之间的CDC反应。N-CuMgAl-LDH系统可以耐受具有不同C H键(C sp3- H,C sp2- H和C sp -H)的N-芳基四氢异喹啉类似物和亲核试剂。与使用Na 2 CO 3的样品相比作为沉淀剂(C-CuMgAl-LDH),N-CuMgAl-LDH显示出较高的催化活性,这可能是由于其较高的表面酸性。在CDC反应中已观察到N-CuMgAl-LDH催化剂具有氧化还原和酸度双重功能。根据获得的催化结果,动力学同位素效应实验和XPS分析,提出了亚胺离子作为关键中间体,这是由于好氧条件下Cu 2+和Cu +的循环所致。