Wang Zi-Lu, Li Qi, Yang Meng-Wei, Song Zhao-Xin, Xiao Zhen-Yu, Ma Wei-Wei, Zhao Jin-Bo, Xu Yun-He
Department of Chemistry, University of Science and Technology of China, 230026, Hefei, P. R. China.
Faculty of Chemistry and Life Science, Changchun University of Technology, 130012, Changchun, P.R. China.
Nat Commun. 2023 Aug 19;14(1):5048. doi: 10.1038/s41467-023-40703-1.
We report a copper-catalyzed ligand-controlled selective 1,2- and 1,4-hydrosilylation of 1,3-enynes, which furnishes enantiomerically enriched propargyl- and 1,2-allenylsilane products in high yields with excellent enantioselectivities (up to 99% ee). This reaction proceeds under mild conditions, shows broad substrate scope for both 1,3-enynes and trihydrosilanes, and displays excellent regioselectivities. Mechanistic studies based on deuterium-labeling reactions and density functional theory (DFT) calculations suggest that allenylcopper is the dominant reactive intermediate under both 1,2- and 1,4-hydrosilylation conditions, and it undergoes metathesis with silanes via selective four-membered or six-membered transition state, depending on the nature of the ligand. The weak interactions between the ligands and the reacting partners are found to be the key controlling factor for the observed regioselectivity switch. The origin of high enantiocontrol in the 1,4-hydrosilylation is also revealed by high level DLPNO-CCSD(T) calculations.
我们报道了一种铜催化的1,3-烯炔的配体控制选择性1,2-和1,4-硅氢化反应，该反应能以高收率和优异的对映选择性（高达99% ee）提供对映体富集的炔丙基硅烷和1,2-烯丙基硅烷产物。该反应在温和条件下进行，对1,3-烯炔和三氢硅烷均显示出广泛的底物范围，并具有优异的区域选择性。基于氘标记反应和密度泛函理论（DFT）计算的机理研究表明，在1,2-和1,4-硅氢化反应条件下，烯丙基铜都是主要的反应中间体，它通过选择性的四元或六元过渡态与硅烷发生复分解反应，这取决于配体的性质。发现配体与反应底物之间的弱相互作用是观察到的区域选择性转变的关键控制因素。高水平的DLPNO-CCSD(T)计算也揭示了1,4-硅氢化反应中高对映选择性的起源。
