Synthesis of Rh(I) and Ir(I) complexes with chiral C-2-multitopic ligands - Structural and catalytic properties

Four multitopic ligands, N,N'-bis[(S)-prolyl)phenylenediamine, N,N'-bis{[(S )-pyrrolidin-2-yl]methyl}phenylenediamine, N,N'-bis[(S)-N-benzylprolyl]phen ylenediamine, N,N'-bis{[(S)-N-benzyl-pyrrolidin-2-yl]methyl}phenylenediamin e, were synthesised and their co-ordination properties with Rh(I) and Ir(I) studied. The complexes were prepared by the reaction of [MC](cod)](2) with AgPF6 and further treatment with the ligand. All ligands form one to one [ ML] species with the above metal ions. The structures of these complexes we re elucidated by analytical and spectroscopic data (elemental analysis, mas s spectroscopy, IR, H-1- and C-13-NMR). Complexes show excellent activities and enantioselectivities up to 30% for the hydrogenation of prochiral olef ins under mild reaction conditions. (C) 2001 Elsevier Science B.V. All righ ts reserved.