Heterogenised catalysts on zeolites. Synthesis of new chiral Rh(I) complexes with (2S,4R)-trans-4-RCOO-2-(t-butylaminocarbonyl) pyrrolidines and (2S,4S)-cis-4-RCONH-2-(t-butylaminocarbonyl) pyrrolidines. Heterogenisation on silica and a USY-zeolite and study of the role of support on their catalytic profile in hydrogenation of olefins
作者:A. Corma、M. Iglesias、F. Mohino、F. Sánchez
DOI:10.1016/s0022-328x(97)00321-5
日期:1997.10
Novel chiral ligands (2S,4R)-2-(t-butylaminocarbonyl)-4-[3-(alkylaminocarbonyl)propanoyloxy]pyrrolidine and (2S,4S)-cis-4-(alkylaminocarbonylamino)-2-(t-butyl-aminocarbonyl)pyrrolidine (4a,b; 9a,b), (a: alkyl = t-butyl; b: alkyl = 3-triethoxysilylpropyl) and their rhodium complexes were synthesised and characterised. The reactions of [Rh(cod)Cl}(2)] and [RhCl(PPh3)(3)] with the chiral ligands in the presence of a non-coordinating anion (PF6-) gave the cationic complexes [Rh(L-2)(ligand)][PF6] (L-2 = cod, PPh3). The structures of these complexes were elucidated by elemental analyses, IR spectroscopy and H-1, C-13 and P-31 NMR measurements. The metal complexes bearing a triethoxysilyl group were covalently bonded to silica and modified USY-zeolite and Rh-heterogenised complexes were obtained. A comparative study (homogeneous versus supported) was made for the catalytic activity in hydrogenation reactions. (C) 1997 Elsevier Science S.A.