Heterogenised Rh(I), Ir(I) metal complexes with chiral triaza donor ligands: a cooperative effect between support and complex
作者:Camino González-Arellano、Avelino Corma、Marta Iglesias、Félix Sánchez
DOI:10.1016/j.ica.2004.04.024
日期:2004.7
Rhodium and iridium complexes of the chiral triaza ligands, N,N'-bis[(2S)-(1-benzylpyrrolidinyl)]methyl}amine (2), N,N'-bis [(2S)-(1-benzylpyrrolidinyl)]methyl}-N-propylamine (3), N,N'-bis[(2S)-(1-benzylpyrrolidinyl)]methyl}-N-[3-(triethoxysilyl)pr-opyl]amine (4),. are described. All ligands form one to one [ML] species with the above metal ions. The structures of these complexes were elucidated by analytical and spectroscopic data (elemental analysis, mass spectroscopy, IR, (1)H and (13)C NMR). The fixation of the preformed triethoxysilyl-rhodium and iridium complexes, on mesoporous solids (MCM-41, SBA-15), and their use, under heterogeneous conditions, for the hydrogenation reactions are reported. The catalytic activity and selectivity of heterogenised complexes are higher to that observed under homogeneous conditions, as a consequence of the complex- and/or reagents-to-support interaction. The stable covalent bond between support and complex allows the recovery and recycling of the heterogenised catalysts for a number of cycles, moreover atomic absorption analysis of the reaction solutions shows that there is not any metal leaching into the solutions. (C) 2004 Elsevier B.V. All rights reserved.