Controllable Isomerization of Alkenes by Dual Visible-Light-Cobalt Catalysis
Controllable Isomerization of Alkenes by Dual Visible-Light-Cobalt Catalysis
复制标题
DOI：
10.1002/anie.201900849
复制
发表时间：
2019-04-16
影响因子：
16.6
通讯作者：
Koenig, Burkhard
中科院分区：
文献类型：
--
作者：
Meng, Qing-Yuan;Schirmer, Tobias E.;Koenig, Burkhard
我们在此报道了烯烃的热力学和动力学异构化可以通过可见光与Co催化的结合来完成。使用Xantphos作为配体，可以获得最稳定的异构体，而使用DPEphos作为配体可以选择性地控制末端烯烃在一个位置上的异构化。供体-受体染料 4CzIPN 的存在进一步加速了反应。在没有任何额外配体的情况下，使用 4CzIPN 和 Co(acac)(2) 可以有效地实现环外烯烃向相应环内产物的转化。光谱和光谱电化学研究表明 CoI 参与 Co 氢化物的生成，随后添加到烯烃中引发异构化。
We report herein that thermodynamic and kinetic isomerization of alkenes can be accomplished by the combination of visible light with Co catalysis. Utilizing Xantphos as the ligand, the most stable isomers are obtained, while isomerizing terminal alkenes over one position can be selectively controlled by using DPEphos as the ligand. The presence of the donor-acceptor dye 4CzIPN accelerates the reaction further. Transformation of exocyclic alkenes into the corresponding endocyclic products could be efficiently realized by using 4CzIPN and Co(acac)(2) in the absence of any additional ligands. Spectroscopic and spectroelectrochemical investigations indicate CoI being involved in the generation of a Co hydride, which subsequently adds to alkenes initiating the isomerization.