Synthesis, Crystal Structures And Properties Studies Of The Metal Complexes Of The 4-aminobenzenesulfonic Acid Pyridine-2- Carboxal Deh Yde Schiff Bases

Our group have been focused on the study of the complexes with taurine for a long time, so have a good knowledge of its coordination chemistry. In order to study the coordination properties of the N atoms and O atoms of sulfonic acid ligand, and to find the best conditions of sulfonic coordination.we selected Schiff base of p-aminobenzenesulfonic acid which is similar to taurine as ligands to synthesis complexes. At the same time, in contrast to o-aminobenzenesulfonic acid Schiff base complexes which our group have done. And we also studied and analyzed the structures of these complexes to find out some laws about the coordination chemistry of the ligands containing sulfonate. We have tried to study the synthetic methods of sulfonic acid ligand complexes. In addition, we have synthesized the"fbsp" ligand that is similar p-aminobenzenesulfonic acid Schiff base which have two N atoms.In this paper, we have synthesized 8 unreported coordination compounds by using p-aminobenzenesulfonic pyridine-2-carboxaldehyde Schiff base(fbsp),hdngb (=p-aminoben-zenesulfonic),htbds(=2-pyridine carboxylic acid),bmbq(=2,5-bis (benzoimidazol-2-yl) Pyrazine), as ligands. And we have synthesized a single crystal of bmbq. These complexes have been characterized by IR, elemental analysis and single crystal X-ray diffraction.They are (1)[Ni(fbsp)2·2H2O]·4 H2O(2)[Zn(fbsp)2·2H2O]·2H2O;(3){[Cu1(fbsp)2-2H2O]·[Cu2(fbsp)2·2H2O]·2H2O}(4)[Mn(4,4'-bpy)(H2O)4]·2dngbh·2H2O;(5)[Zn(4,4'-bpy)(H2O)4]·2dngb·2H2O;(6)[Cu(tbds)4]·2H2O;(7)bbm-q;(8) [Cd2 (bbmq)2Cl4]·2H2O respectively At the same time, the Electrical properties,DTG and lumin-escent properties of some complexes have been studied as well. The main work is shown as follows:1. Two novel coordination polymers have been synthesized by the reaction of p-aminobenzenesulfonic acid salicylic Schiff base ligand and transition metal ions:A OD coordination complex [Ni(fbsp)2·2H2O]·4H2O (1) has been prepared by the reaction of the ligand fbsp and NiCl2-2H2O in presence of acetonitrile-water solution. The crystal structure of complex (1) belongs to orthogonal, space group Pna21. Each Ni(Ⅱ) ion is six-coordinated by two water O atoms, two imine N atoms and two N atoms of the ligand fbsp, completing the deformed Octahedral geometry. The [Zn(fbsp)2·2H2O]·2H2O(2) belongs to triclinic, space group P (?). is also a OD coordination polymer, which is six-coordinated by two water O atoms, two imine N atoms and two N atoms of the ligand fbsp,and is deformed Octahedral geometry. The [Cu(fbsp)2·2H2O]·H2O(3) belongs to Monoclinic, space group P21/n. is also a OD coordination polymer, which is six-coordinated by two water O atoms, two imine N atoms and two N atoms of the ligand fbsp,and is deformed Octahedral geometry.2. To explore the synthesis of the complexes of sulfonic acid ligand Schiff base. We tried to change the reaction conditions to synthesize its c omplex, But unexpectedly, the ligand of(fbsp) has decomposited. We obtained 3 complexes (4) (5) (6).We first use the p-aminobenzenesulfonic pyridine-2-carboxaldehyde Schiff base(fbsp) as ligand material,4,4'-bipyridine as the second ligand,with the weak acid, high temperature, high pressure conditions, in the water/ethanol mixtures, with manganese, copper, zinc salt reaction, the main ligand (fbsp) have decomposited and we obtained [Mn(4,4'-bpy)(H2O)4]·2dngbh·2H2O(4);[Zn(4,4'-bpy)(H2O)4]·2dngbh·2H2O(5);[Cu(tbds)4]·2H2 O(6); Cu(4,4'-bpy) (tbds)2(7). The result of X-ray crystallographic analysis indicates that complex (4) crystallizes is Monoclinic, space group P21/c, The Mo(Ⅱ) center is six coordinated in a deformed octahedral geometry, bonding to four water O atoms, two N atom from 4,4'-bipyridine molecules. The crystal system complexes (6) (7) is triclinic, space group P (?), The M(Ⅱ) center is six-coordinated in a deformed octahedral geometry.3. In order to investigate the coordination ability of (fbsp) ligand N atoms, we successfully synthesized 2,5-bis (benzoimidazol-2-yl) Pyrazine ligands,what is more, we trained its single crystal (bbmq) (7), also synthesized a new complex [Cd2 (bbmq)2Cl4]·2H2O (8).We have used 2,5-dimethyl pyrazine and O-phenylene diamine as starting materials through multi-step synthesis to nurture (bmbq) ligand crystal. Bmbq is in ethanol and water and CdCl2 is resolved, X-ray crystallographic analysis (7) show that:single crystal (bbmq) (7) is monoclinic, Cc space group, is a rigid ligand. Complex [Cd2 (bbmq)2Cl4]·2H2O(8) belongs to triclinic, space group P T, the central atom Cd is six-coordinated, a deformed octahedral geometry.This paper have synthesised the ligand crystal, seven complexs which have not been reported, the complex were characterized by elemental analysis, infrared spectroscopy and X-ray diffraction, and it's crystal structure is deeply discussed, found:①by comparing the the oxygen atoms of o-position sulfonic acid, the oxygen atom of is a bit harder to coordinate, currently, there are no coordination complexes of the p-position sulfonic acid wich were synthesised.②with high temperature conditions, sulfonic acid Schiff easily was decomposited to carboxylic acid and③the coordination ability of N atoms of sulfonic acid Schiff base is very strong compared with pyrazine N atoms and the imidazole ring N atoms.; Mainly reasons is due to the environment of N atoms。④the discussion of the five-water cluster of complex (1) and the water chain of complex (6) and (7).