Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
University of Perugia, Department of Chemistry, Biology and Biotechnology, 06122 Perugia, Italy.
J Am Chem Soc. 2023 Mar 8;145(9):4994-5000. doi: 10.1021/jacs.3c00858. Epub 2023 Feb 24.
Chiral organosilanes do not exist in nature and are therefore absent from the "chiral pool". As a consequence, synthetic approaches toward enantiopure silanes, stereogenic at silicon, are rather limited. While catalytic asymmetric desymmetrization reactions of symmetric organosilicon compounds have been developed, the utilization of silanes in a dynamic kinetic asymmetric transformation (DYKAT) or dynamic kinetic resolution (DKR) would significantly expand the breadth of accessible -stereogenic compounds. We now report a DYKAT of racemic allyl silanes enabled by strong and confined imidodiphosphorimidate (IDPi) catalysts, providing access to -stereogenic silyl ethers. The products of this reaction are easily converted into useful enantiopure monohydrosilanes. We propose a spectroscopically and experimentally supported mechanism involving the epimerization of a catalyst-bound intermediate.
手性有机硅烷在自然界中并不存在,因此不存在于“手性库”中。因此,合成手性硅烷的方法相当有限,硅原子具有立体中心。虽然已经开发出对称有机硅化合物的催化不对称去对称化反应,但在动态动力学不对称转化(DYKAT)或动态动力学拆分(DKR)中使用硅烷将显著扩大可获得的 -立体化合物的范围。我们现在报告了通过强而受限的亚氨基二膦酰亚胺(IDPi)催化剂实现的外消旋烯丙基硅烷的 DYKAT,从而获得了 -立体硅基醚。该反应的产物很容易转化为有用的对映纯单氢硅烷。我们提出了一个光谱和实验支持的机制,涉及催化剂结合中间体的差向异构化。