Preparation, Characterization Of Chiral Lanthanide Complexes And Its Asymmetric Catalytic Properties

Two series of ligands derived from d-camphor-p-sulfonate and 1-cysteine and 52 new chiral schiff base lanthanide complexes have been synthesized and characterized by elemental analysis, thermal analysis, molar conductance, UV-Vis, IR, NMR, XPS and CD spectra. The possible binding structure of these complexes has been proposed. The catalytic properties of chiral lanthanide complexes in asymmetric synthesis of α-aryl propanoic acid have also been studied. It has been found that some of these complexes have shown good catalytic activity.(1) Four new chiral d-camphor-P-sulfonate schiff base ligands have been prepared firstly from d-camphor-P-sulfonate and different amine (hydroxylamine, aminothiourea, p-nitrophenyl-hydrazine, o-methyl aniline); its chiral lanthanide complexes have been synthesized and characterized by elemental analysis, thermal analysis, molar conductance, UV-Vis, IR, NMR, XPS and CD spectra. The possible binding models of these complexes have also been discussed.(2) Three new chiral 1-cysteine schiff base ligands have been prepared firstly by the reaction of 1-cysteine hydrochlorate with different oxo compound (acetylbenzene, benzoin and acetylacetone) and 20 new chiral schiff base lanthanide compounds have been synthesized from the ligands and the metal salts. These compounds have been characterized by elemental analysis, thermal analysis, molar conductance, UV-Vis, IR, NMR, XPS and CD spectra. The possible binding models of these complexes have been proposed.(3) Optical active a-aryl propanoic acid has been synthesized in high yields starting from (6-methoxy-2-naphthyl) propan-1-one catalyzed by the chiral lanthanide complexes in "one-pot". The results indicated that these chiral catalysts prepared have high catalytic activity on a certain extent.