Sequential Transformation of Terminal Alkynes to 1,3-Dienes by a Cooperative Cobalt Pyridonate Catalyst
作者:Xuewen Zhuang、Jia-Yi Chen、Zhuoyi Yang、Mengjing Jia、Chengjuan Wu、Rong-Zhen Liao、Chen-Ho Tung、Wenguang Wang
DOI:10.1021/acs.organomet.9b00486
日期:2019.10.14
1 bearing a phosphinopyridonate ligand for sequential transformation of aryl terminal alkynes to (E,Z)-1,3-dienes with excellent stereoselectivity. By cooperative metal–ligand reactivity, 1 reacts readily with the terminal alkynes to afford the alkynyl cobalt intermediate for dimerization, producing (E)-1,3-enynes, and then to smoothly catalyze reduction of the acetylene unit to the olefin by H3N·BH3
我们描述了带有膦基吡啶酮配体的钴(II)催化剂1,用于将芳基末端炔烃连续转化为具有出色的立体选择性的(E,Z)-1,3-二烯。通过金属-配体的协同反应,1容易与末端炔烃反应以提供炔基钴中间体进行二聚,生成(E)-1,3-炔烃,然后平稳地催化乙炔单元被H 3还原为烯烃N·BH 3。在化学计量反应和DFT计算的基础上,提出了一个可行的二聚和转移加氢催化循环,表明钴催化剂具有通过吡啶鎓钴的合作活化胺-硼烷以及末端炔烃的能力。