Hydrosilylation of alkenes catalysed by rhodium complexes immobilized on silica via a pyridine group

Abstract

2-(2-Trimethoxysilylethyl)pyridine, together with 3-methacryloxy)propyltrimethoxysilane, was used to prepare a series of rhodium carbonyl complexes bound to silica via a pyridine group. The rhodium complex Rh,(CO),CI, (Rh,) was used as the starting compound, and the immobilized complexes were prepared by four different routes which yielded both surface-bonded complexes and complexes bonded within the silicate matrix. These complexes were efficient catalysts of hydrosilylation of octene by triethoxysilane. All the immobilized complexes were more than their homogeneous analogues and some could be re-used.

Preparation and use of hybrid organic–inorganic catalysts

“…Capka et al prepared various silica-supported Rh pyridine complexes, either by grafting of 2-(2-trimethoxysilylethyl)pyridine or by co-condensation of the same compound with TEOS (139). Tetracarbonyl(m,m 0 -dichloro)dirhodium(I) was added during different stages of the preparation.…”

Pt(0)-Based Catalyst Supported on Silica Containing Di(ethylene oxide) Units for Hydrosilylation of Unsaturated Carbon−Carbon Bonds

“…While immobilization of soluble transition-metal complexes on solid supports has given rise to much attention, 5,6 only few cases dealing with supported Pt catalyst for hydrosilylation have been reported. [7][8][9][10][11] Hybrid organic-inorganic materials prepared from molecular precursors containing at least two hydrolyzable Si(OR) 3 groups constitutes an expanding class of materials due to their potential applications in catalysis, adsorption, and separation, for example. 12 In the course of our investigations in this field, we found an original and efficient route to an immobilized platinum catalyst for hydrosilylation of unsaturated carbon-carbon bonds.…”

“…While immobilization of soluble transition-metal complexes on solid supports has given rise to much attention, , only few cases dealing with supported Pt catalyst for hydrosilylation have been reported. – …”