Hu Aiguo, Yee Gordon T, Lin Wenbin
Department of Chemistry, CB #3290, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
J Am Chem Soc. 2005 Sep 14;127(36):12486-7. doi: 10.1021/ja053881o.
Novel heterogenized asymmetric catalysts were synthesized by immobilizing preformed Ru catalysts on magnetite nanoparticles via the phosphonate functionality and were characterized by a variety of techniques, including TEM, magnetization, and XRD. These nanoparticle-supported chiral catalysts were used for enantioselective heterogeneous asymmetric hydrogenation of aromatic ketones with very high enantiomeric excess values of up to 98.0%. The immobilized catalysts were easily recycled by magnetic decantation and reused for up to 14 times without loss of activity and enantioselectivity. Orthogonal nature of the present catalyst immobilization approach should allow the design of other superparamagnetic nanoparticle-supported asymmetric catalysts for a wide range of organic transformations.
通过膦酸酯官能团将预制的钌催化剂固定在磁铁矿纳米颗粒上，合成了新型非均相不对称催化剂，并通过包括透射电子显微镜（TEM）、磁化和X射线衍射（XRD）在内的多种技术对其进行了表征。这些纳米颗粒负载的手性催化剂用于芳香酮的对映选择性非均相不对称氢化反应，对映体过量值高达98.0%。固定化催化剂通过磁倾析法易于回收，并可重复使用多达14次，而不会损失活性和对映选择性。本催化剂固定化方法的正交性应允许设计用于广泛有机转化的其他超顺磁性纳米颗粒负载的不对称催化剂。
