Enantioselective Hydrosilylation of Ketones Catalyzed by a Readily Accessible N-Heterocyclic Carbene-Ir Complex at Room Temperature
作者:Kanako Shinohara、Shun Kawabata、Hanako Nakamura、Yoshiki Manabe、Satoshi Sakaguchi
DOI:10.1002/ejoc.201402279
日期:2014.9
complexes. Subsequent treatment of the resulting silver compound with [IrCl(cod)]2 yielded monodentate IrCl(cod)(NHC), which was stable in air. The NHC–Ir complex facilitated efficient asymmetric hydrosilylation of ketones using (EtO)2MeSiH under ambient conditions. A chiral ligand containing an isobutyl stereodirecting group was found to be the best ligand for the functionalized NHC–Ir complexes that were
从手性α-氨基酸衍生物如β-氨基醇合成了一系列功能化的唑鎓化合物。由此获得的羟基-酰胺官能化的唑盐与 Ag2O 反应得到 N-杂环卡宾-Ag (NHC-Ag) 配合物。随后用[IrCl(cod)] 2 处理所得的银化合物产生单齿IrCl(cod)(NHC),其在空气中稳定。NHC-Ir 复合物在环境条件下使用 (EtO)2MeSiH 促进了酮的有效不对称氢化硅烷化。发现含有异丁基立体定向基团的手性配体是所检查的功能化 NHC-Ir 配合物的最佳配体。发现催化剂ee和产物ee之间存在线性关系。