Synthesis And Structure Of Coordination Compounds Based On Schiff Bases

Six compounds were obtained by the reactions of transition metal ions with two schiff base ligands, where the two schiff base ligands are salicylidene-2-Amino-2-methyl-1,3-propanediol(H3L 1) and 4-(2'-Pyridylimine) benzoicacid(HL2). All the compounds were determined by X-ray single crystal diffraction and characterized by FT-IR and ICP.The formulae of the six compounds are as follows:(1) [Ni(H2L1)2]·CH3OH(2) [Ni(H2L1)2]·CH3CN(3) [Mn2Ni2(HL1)4](ClO4)2·5C2H5OH(4) [Cu(H2L1)Cl]·H2O(5) Cu2(HL2)2(μ2-Cl)2Cl2(6) [Co(HL2)2Cl2]·CH3OHThe structure of compound 1 consists of mono-nulcear nickel, which is linked by intermolecular hydrogen bonds to form one-dimensional zig-zag chains. The structure of compound 2 is similar to compound 1. Compound 3 is a hetero-metal MnⅢ2NiⅡ2 tetranuclear cluster, the structure consists of an incomplete face-sharing double cube that is composed of two Mn(III) and two Ni(II) ions. The reaction between Cu(II) and H3L1 ligand gives rise to compound 4, which shows 1D chain formed by hydrogen bonding interactions. Compound 5 is a di-nuclear Cu(II) withμ2-Cl-bridged composed of HL2 ligand and Cu(II). The carboxylate oxygen of the Schiff base ligand HL2 engages in intermolecular hydrogen bonding with terminal Cl-, giving two-dimensional layer-like structure. Compound 6 is comprised of Co(II) and HL2 ligand containing one lattice methanol molecule, which displays a 1D ladder-like chain linked by hydrogen bonding interactions.In order to further study the synthesis and self-assembly of the Schiff base complexes, we investigated and summarized the influence of the method of growing single, the kind of solvent, the reaction conditions, the ratio of reactants and ions, etc. on the appearance and crystal structure of the complexes.