Searching for highly active cobalt catalysts bearing Schiff base ligands for Markovnikov-selective hydrosilylation of alkynes with tertiary silanes
作者:Maciej Skrodzki、Victor Ortega Garrido、Aurelio G. Csáky、Piotr Pawluć
DOI:10.1016/j.jcat.2022.05.002
日期:2022.7
high activity and selectivity in alkyne hydrosilylation reactions is an interesting current challenge. Herein, we report that a cobalt(II) complex bearing pyrimidine-imine-2H-imidazole ligand activated by LiHBEt3 exhibits not only high catalytic activity, but also unprecedented tolerance towards tertiary silanes in highly regioselective Markovnikov hydrosilylation of aliphatic and aromatic terminal alkynes
为稳定的钴(预)催化剂寻找简单且易于合成的配体,以确保炔烃氢化硅烷化反应中的高活性和选择性,是当前一个有趣的挑战。在此,我们报告了由 LiHBEt 3活化的带有嘧啶-亚胺-2 H-咪唑配体的钴 (II) 配合物在脂肪族和芳香族末端炔烃的高区域选择性马尔科夫尼科夫氢化硅烷化中不仅表现出高催化活性,而且对叔硅烷具有前所未有的耐受性得到α-乙烯基硅烷。此外,在[Co(L)Cl 2 ]/LiHBEt 3存在下,二苯基硅烷可以有效地氢化各种1-芳基-2-(三甲基甲硅烷基)乙炔。催化系统以高选择性产生 ( E )-1-aryl-1,2-bis(silyl)乙烯。对于钴催化的甲硅烷基乙炔的氢化硅烷化,很少观察到这种选择性。