Synthesis, Characterization And Crystal Structure Of The Complexes With Taurine 3-Formylsalicylic And Taurine 5-Formylsalicyliclaldehyde Schiff Base

Taurine, a non-protein amino acid containing sulfur, is indispensable to human beings and animals. It has been widely used in medicine, food and chemical industry because of its'unique medical and physiological effects. Schiff base complexes containing sulfur and complexes of amino acid Schiff bases have become the hotspot of research in recent years due to their bio-activities, such as antiviral antibacterial activities and catalytic-activities. 3-fromylsalicylic, the derivative of salicylaldehyde, is an important organic ligand that can be used to synthesize centrosymmetric polynuclear complexes. In order to abundant and develop chemistry of sulfoacid coordination, we choose the taurine 3-formysalicylic Schiff base (TFSSB) as our research subject and renew the taurine 5-formylsalicylic Schiff base(5-TFSSB) . In the research process of this paper, three transition metal complexes of TFSSB and two transition metal complexes of 5-TFSSB were synthesized and their crystal structures were obtained. The XRD show the five complexes in the paper belongs to polyunclear complexes. The crystal structure of the complex [Cu₂(TFSSB)₂(H₂O)₂][Cu(H₂O)₆] ·5H₂O(â… ) belongs to triclinic with space group P-1. It is an anionic complex in which, three Cu(â…¡) have two coordination methods. The molecule has a centrosymmetric dinuclear copper coordinated anion with a trans arrangement of the two Cu(â…¡), two TFSSB ligands and two water ligands. The other Cu(â…¡) were six coordinated H2O to form the octahedral geometry coordinated cation. Besides the electrostatic force, there are also hydrogen bonds between anions and cations. The compound was assembled by hydrogen bonds to form three-dimensional structure. The crystal structure of the complex[Cu3(TFSSB)2·(H2O)4·4H2O]n(â…¡), which belongs to monoclinic with space group P 21/n. The molecule has a centrosymmetric dinuclear copper with a trans arrangement of the two TFFSB ligands, two units were linked by the other copper to form one-dimensional infinite chain polymer. The compound was assembled by hydrogen bonds to form three-dimensional structure. The crystal structure of the complex [Co4(OH)4(TFSSB)2(Phen)2(H2O)2]·10H2O ( â…¢) belongs to monoclinic with space group P 21/c. The complex is a centrosymmetric tetranuclear cobalt. The molecule can be viewed as two planar [Co2(OH)(TFSSB)(Phen)(H2O)] units tied together by two hydroxyl atoms (O8, O8A). The framework of cobalt and bridging oxygen atoms in the complex has the appearance of two connected face-sharing cubes, each with one vertex missing. Four cobalt (II) ions are six-coordinate with octahedral geometry. The molecule was linked by hydrogen bonds to form a three-dimensional netlike structure. The crystal structure of the complex [Zn(5-TFSSB)(Bipy)(H2O)]2·2H2O(â…£) belongs to triclinic with space group P-1. The central Zn(â…¡) was six coordinated with two O atoms, one N atom of the ligand 5-TFSSB, two N atoms of 2,2'-Bipy and one O atoms of the coordinated water to form a octahedron structure. There are two complex molecules in one asymmetric unit, these two molecules were linked by hydrogen bond and aromatic-ring stacking interaction along two directions, which also assembled the units to form netlike structure. The crystal structure of the complex[Cu3(5-TFSSB)2(Bipy)4][Cu(5-TFSSB)2]·2H2O (â…¤) belongs to triclinic with space group P-1. It is an anionic complex in which, four Cu(â…¡) have two coordination methods. The molecule has a centrosymmetric trinuclear copper coordinated cation with a trans arrangement of the three Cu(â…¡), two TFSSB ligands and four 2,2'-Bipy ligands. The other Cu(â…¡) were four coordinated with two O and two N atoms of the 5-TFFSB to form a square planar anion. Besides the electrostatic force, there are also hydrogen bonds between anions and cations. The compound was assembled by hydrogen bonds to form three-dimensional structure.The complexes have also been characterized by elemental analysis and IR spectrum.