HETEROGENIZED CATALYSTS ON ZEOLITES - SYNTHESIS OF NEW CHIRAL RH(I) COMPLEXES WITH -TRANS-4-RCOO-2-(T-BUTYLAMINOCARBONYL)PYRROLIDINES AND )-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

Novel chiral ligands -4-[3-(alkylaminocarbonyl)propanoyloxy]pyrrolidin e and arbonylamino)-2-(t-butyl-aminocarbonyl)pyrrolidine (4a,b; 9a,b), (a: alkyl = t-butyl; b: alkyl = 3-triethoxysilylpropyl) and their rho dium complexes were synthesised and characterised. The reactions of [{ Rh(cod)Cl}(2)] and [RhCl(PPh3)(3)] with the chiral ligands in the pres ence of a non-coordinating anion (PF6-) gave the cationic complexes [R h(L-2)(ligand)][PF6] (L-2 = cod, PPh3). The structures of these comple xes were elucidated by elemental analyses, IR spectroscopy and H-1, C- 13 and P-31 NMR measurements. The metal complexes bearing a triethoxys ilyl group were covalently bonded to silica and modified USY-zeolite a nd Rh-heterogenised complexes were obtained. A comparative study (homo geneous versus supported) was made for the catalytic activity in hydro genation reactions. (C) 1997 Elsevier Science S.A.