| A wide number of studies have focused on amino acid Schiff base and their metal complexes due to the important role of amino acids in living organisms. Helical structures have also attracted interest from coordination chemists, not only because of their intriguing structures, but also owing to their potential application in molecular recognition, nonlinear optical materials, asymmetric catalysis, enantiomorph separation and biologic pharmacy. Therefore, we try to study helical structure of metal complexes base on amino acid Schiff bases.In our works, L-threonine, D-threonine, L-leucine, L-isoleucine, glycine reacted with2-hydroxy-l-naphthaldehyde are formed five Schiff-base ligands, respectively. And with transition metals through the solvent evaporation method for assembly. Herein, a series of amino acid Schiff base metal complexes, namely {[Zn2(nap-L-Thr)2(H2O)2]·H2O}n (1),{[Zn2(nap-D-Thr)2(H2O)2]·H2O}n (2),[Cu(nap-L-Leu)]n (3),{[Cu(nap-L-Ile)(H2O)]·H2O}n (4),[Cu(nap-Gly)(H2O)]n (5),[Cu2(Nap-Gly)·2H2O(H2O)(pyr)·(CH3OH)2](6) and some zero dimensional complexes Mn2C2O4(bpy)2·C8H6O2·ClO4(7), CuNap(bpy)Cl (8),[Cu(C5H11O2N)(phen)H2O]·2H2O (9) have been successfully synthesized. Complex1～5exhibit ID structures. Among them, complexes1and2are enantiomers with right-handed helical chain of1and left-handed chain of2, complex3and4both are left-handed chains, complex5is zigzag chain. While complex6is double-core copper of pyrazine bridge structure, complexes7is double-core manganese of oxalic acid bridge structure, complex8and9both are single-core structures. All of them are characterized by single-crystal X-ray diffraction and IR, and some of them are characterized by UV-visible and X-ray powder diffraction, thermogravimetric analysis, circular dichroism spectra measurements, luminescence properties, magnetic properties selectively. |
