Enantiopure bisphosphine ligands with appended crown ether groups as regulation sites for Rh-mediated hydrogenations
作者:Héctor Fernández-Pérez、Ignasi Mon、Antonio Frontera、Anton Vidal-Ferran
DOI:10.1016/j.tet.2015.02.073
日期:2015.7
efficient preparation of a set of enantiopure bisphosphine ligands, whose backbone incorporates an array of diverse crown ethers as distal regulation sites via well-defined supramolecular interactions to tune the catalytic properties of the bisphosphine groups. These new ligands enabled very good catalytic activity in rhodium-mediated asymmetric hydrogenations at low catalyst loadings, while the enantioselectivity
本文报道了对映体纯双膦配体的有效制备,其骨架通过明确定义的超分子相互作用掺入了一系列不同的冠醚作为远端调节位点,以调节双膦基的催化性能。这些新的配体在低催化剂负载下,在铑介导的不对称氢化中具有非常好的催化活性,而对映选择性仍保持中等水平。通过适当的双膦配体和不同的调节剂的组合,获得了对氢化反应的对映选择性略有正调节作用。