Chiral NHC‐Complexes with Dioxolane Backbone Heterogenized on MCM‐41. Catalytic Activity

• DOI: 10.1002/cctc.201100119
• Publication Date: 2011-06-20T13:13:30Z
• Authors: Gonzalo Villaverde; Avelino Corma; Marta Iglesias; Félix Sánchez
• Keywords: Benzonitrile; Dioxolane; Asymmetric hydrogenation

Abstract Rhodium, palladium, and gold complexes of chiral (NHC)–dioxolane–amino ligands were prepared. Herein, new methods for the heterogenization NHC‐chiral on porous silica supports are demonstrated facile recovery recycling these expensive catalysts. Activity, selectivity, recyclability investigated compared to that analogous homogeneous catalysts asymmetric hydrogenation reactions. The compounds characterized by using a variety methods, including solid state cross‐polarization magic‐angle spinning (CP MAS) 13 C NMR, FT‐IR spectroscopy, elemental analysis. Heterogenized rhodium(I) palladium(II) could be used at least four times without loss activity or enantioselectivity. (NHC)–gold(I) easily immobilized recycled treatment with benzonitrile during washing steps between cycles. This maintained