Divergent synthesis of flavones and aurones via base-controlled regioselective palladium catalyzed carbonylative cyclization
作者:Shan Xu、Huaming Sun、Mengyuan Zhuang、Shaohua Zheng、Yajun Jian、Weiqiang Zhang、Ziwei Gao
DOI:10.1016/j.mcat.2018.03.021
日期:2018.6
A regioselective approach for construction of 5-membered and 6-membered flavonoid is established by Pd catalyzed carbonylative cyclization of 2-iodophenol with terminal alkynes using different amine bases under mild reaction condition. The catalytic experiments found that piperazine preferentially accelerate 6-endo cyclization, and triethylamine mediated Pd catalyzed 5-exo cyclization. Under optimized
在温和的反应条件下,使用不同的胺碱,通过钯催化的2-碘苯酚与末端炔烃的羰基化环化反应,建立了一种构建5元和6元类黄酮的区域选择性方法。催化实验发现,哌嗪优先促进6-内环化,三乙胺介导的Pd催化5-外环化。在优化的反应条件下,Pd催化的羰基化方案成功地以优异的收率和区域选择性应用于39个实例的各种结构。