Pd-catalyzed aerobic oxidative coupling of vinylboronic acids and electronically unbiased alkyl olefins provides regioselective access to 1,3-disubstituted conjugated dienes. Catalyst-controlled regioselectivity is achieved by using 2,9-dimethylphenanthroline as a ligand. The observed regioselectivity is opposite to that observed from a traditional (nonoxidative) Heck reaction between a vinyl bromide
Pd 催化的
乙烯基硼酸和电子无偏烷基烯烃的有氧氧化偶联提供了对 1,3-二取代共轭二烯的区域选择性访问。催化剂控制的区域选择性是通过使用 2,9-二甲基
菲咯啉作为
配体来实现的。观察到的区域选择性与从
溴乙烯和烯烃之间的传统(非氧化)Heck 反应观察到的相反。DFT 计算研究表明,2,9-二甲基
菲咯啉
配体的空间效应促进了烯烃内部位置的 CC 键形成。