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

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, anticancer and antibacterial activities, and catalytic-activities. 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, however, there are few papers reported its' Schiff base transition metal complexes. It is reported that most Schiff base complexes of salicylaldehyde and its' derivatives possess favorable bio-activities and have wide applied prospect. 5-fromylsalicylaldehyde, the derivative of salicylaldehyde, is an important organic synthetic intermediate that can be used to synthesize macrocyclic complexes, drugs and photochromic compounds. In order to systematically research the coordination chemistry of sulfoacid and find out some laws, we choose the taurine 5-formylsalicylic Schiff base(TFSSB) as our research subject, In the research process of this paper, six transition metal complexes of TFSSB were synthesized and their crystal structures were obtained. They are [Cu(TFSSB)(H2O)]·H2O(Ⅰ), [Co(TFSSB)(H2O)3]·2H2O(Ⅱ), [Zn(TFSSB)(Phen)(H2O)]·3.68H2O(Ⅲ), [Ni(TFSSB)(Phen) (H2O)]·3.75(H2O)( Ⅳ), [Co(TFSSB)(Phen)(H2O)]·(3H2O)(C2H5OH)(Ⅴ) and [Cu(TFSSB)2] [Cu2 (Phen)2(OH)2(H2O)2]·6H2O(Ⅵ). And the weak interactions of the crystals were discussed.The crystal structure of the complex [Cu(TFSSB)(H2O)]·H2O (Ⅰ) belongs to monoclinic with space group P2(1)/c. The central Cu(Ⅱ) was four coordinated with two O atoms, one N atom of the tridentate ligand and one O atom of the coordinated water to form a square plane structure. The distance between the central Cu(Ⅱ) and the O atom of the formyl group belonging to the ligand of an adjacent unit is 2.877(3) ?, indicating that there is weak interaction between these two atoms. The complexes was linked by this interaction to form one-dimensional structure. The compound was assembled by hydrogen bonds to form supra-molecule.The crystal structure of the complex [Co(TFSSB)(H2O)3]·2H2O(Ⅱ), which belongs to triclinic with space group P-1, is the first crystal structure of Co complex of Schiff base derived from taurine. The central Co(Ⅱ) was six coordinated with two O atoms, one N atom of the ligand TFSSB and three 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, which also assembled the units to form three-dimensional structure.The crystal structure of the complex [Zn(TFSSB)(Phen)(H2O)]·3.68H2O(Ⅲ) is the first crystal structure of Zn complex of Schiff base derived from taurine. Its' crystal structure belongs to triclinic with space group P-1. The central Zn(Ⅱ) was six coordinated with two O atoms, one N atom of the ligand TFSSB, two N atoms of Phen 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, which also assembled the units to form netlike structure. Furthermore, the structure was stabilized by aromatic-ring stacking interaction along two directions.The crystal structure of the complex [Ni(TFSSB)(Phen)(H2O)]·3.75(H2O)(Ⅳ) belongs to triclinic with space group P-1. The central Ni(Ⅱ) was six coordinated with two O atoms, one N atom of the ligand TFSSB, two N atoms of Phen and one O atoms of coordinated water to form a octahedron structure. There are two complex molecules, which were linked by hydrogen bonds, in one asymmetric unit. The asymmetric units were assembled by hydrogen bonds and aromatic-ring stacking interaction along two directions to form netlike structure. The crystal structure of the complex [Co(TFSSB)(Phen)(H2O)]·(3H2O)(C2H5OH) (Ⅴ) belongs to monoclinic with space group C2/c. The central Co(Ⅱ)was six coordinated with two O atoms, on...