Enantiopure Narrow Bite-Angle POP Ligands: Synthesis and Catalytic Performance in Asymmetric Hydroformylations and Hydrogenations
作者:Héctor Fernández-Pérez、Jordi Benet-Buchholz、Anton Vidal-Ferran
DOI:10.1002/chem.201404731
日期:2014.11.17
center, as evidenced by X‐ray crystallography. These new ligands enabled very good catalytic properties in the Rh‐mediated enantioselective hydrogenation and hydroformylation of challenging and model substrates (up to 99 % ee). Whereas for asymmetric hydrogenation the optimal P–OP ligand depended on the substrate, for hydroformylation, a single ligand was the highest‐performing one for almost all studied
本文报道了一组窄咬角P-OP配体的制备,其配体的骨架包含立体碳原子。合成是基于Corey-Bakshi-Shibata(CBS)催化的磷酰胺的不对称还原。通过适当组合立体生成碳原子,其取代基和亚磷酸酯片段的构型,选择性地调节了所得的1,1-P-OP配体的结构,这对于在金属中心周围提供刚性环境至关重要, X射线晶体学证明。这些新的配体在具有挑战性和模型底物的Rh介导的对映选择性加氢和加氢甲酰化反应中具有非常好的催化性能(ee高达99% ee))。对于不对称氢化,最佳的P–OP配体取决于底物,对于加氢甲酰化而言,对于几乎所有研究的底物,单个配体的性能最高:它在两个磷连接基团之间包含一个R构型的立体碳原子,并且一个S构型的3,3'-二苯基取代的联芳基单元。