Synthesis, Characterization And Structures Of The Complexes With Pyridine-2, 6-dicarboxylic And Taurine

Pyridine-2,6-dicarboxylic acid(H2DPC) possess biological active in the body of the animal and plant. Its dervivatives and complexes were extensively and deeply studied and were used to all sorts of fields. Metal complexes with H2DPC ligand have been simply reviewed.The ternary complex of the formula [Co(DPC)(phen)(H20)]2H20 (1) was obtained for the first time in the mixed solvents of H20-C2H5OH and the PH value of the reaction solution was strictly controlled at 6.7 . Complex (1) crystallizes in the triclinic space group PT witha7.8 180(1 4)A,b=9.2896( I 8)A,c1 4.048(3)A, a=8 1.477(1)0, ~ 1.456(8)0, y =72.970(15) 0 V=958.7(3)A~. Z=2,S=I .034.The coordination geometry around Co( IL) is distorted octahedral. The 1,1 0-phenantbroline(phen) ligand is normally bidentate providing two 0 and one N atoms to coordinate with metal ion. The last coordination 0 atom is offered by H20. The structure is held together by hydrogen bonds via carboxylate-water as well as water-water molecules,which form a three-dimensional network. And the crystal exists very strong ii -stacking interactions.The reaction of H2DPC,NiC12-6H20 and phen in H20-CH3OH with equal molar, Two new complexes(2) and (3) with different colors and forms were, obtained successively.And the formulas of which are [Ni(phen)3][Ni(DPC)2]<1 I .5H20 And [Ni(phen)2(H20)2][Ni(DPC)2] 6H20- 1 /2CH3OH respectively. Complex(2) crystallizes in the monoclinic .space group C2/c with a=29.863(3)A,b 14.971 (2)A, c=24.63 8(3)A,a= y =900, P =104.800(1 0)0,V 10650(2) A3, Z=8, S-O.883.Complex(3) crystallizes in the triclinic space group PT with a10.0870A, bzl 4.585(2)A, c=1 4.934(2)A, a=74.050( 10)0,78.580(10)0, y =75.210(10)0, V2023.l (4)A~, Z=2, S=1 .052.The [Ni(DPC)2]2 anions of the two ionic complexes are most similar. While the cations are different from each other. The structure of Complex(3) is stabilized by an extensive network of hydrogen bonding interactions. But in the camplex(2) there is no hydrogen bond found between the anion and cation. They held together just through stati electrictity interaction.Another new complex of formula [Cu(HDPC)2] (HOx) 2-6H20(4) have been synthesized in the mixed solvents of H20-C2H5OH and the PH value was controlled at 7.0. The crystal belongs to rnonoclinic system, space group C21c, with a=1 8.423(3)A, WI 0.384(2)A, c1 9.1 39(2)A, a y 900, ~31 11.050(10) ~, V34 I 7.0(9)A~, Z=4,Sl .041.The position of Cu( H) is particular. The distances from Cu to two HDPC ligand plane, and to two HOx joined by hydrogen bonds plane as well as to the two equivalent equatorial plane are all the same.The part of Cu(HDPC)2 possess an approximately D2d symmetry. The whole3system is also linked together by many hydrogen bonds which form a three-dimensional network.. So it has a high symmetry and stability.complexes(1 -4) have been characterized by elemental analysis, IR, TG-IR, cyclic voltametric. At the same time, the HF method is used to calculate the quantum chemistry of the complexes(Th-3). They were characterized further by variable-temperature megnetic susceptibility. The result indicated that complexes(Th-3) feature antiferromagnetism at low temperature(<30K).In the cause of the synthesis of schiff base from taurine, we obtained unexpectedly a novel and interesting enneanuc~ear nickel complex with taurine whose foumula is K3Na[Ni9(NH2CH2CH2SO3)6(Ac)6(H20)6(0H7)6(C03)2]. It crystallized in rhombohedral space group R 3 c, with a=19.529(l)A, b19.529(l)A, c39.543(6)A, a P 90~, y =1200, V=1 3061 (2)A~, Z=6, 5=1.029. There is no M-M bond between Ni and Ni atoms in the complex, They connected by the 01-F group which is bonded in a P2 fashion to three nickel atoms. In the clathrate complex, there wrap up two C032 group of which the three 0 are bondecL There are two co-ordination surroundings among nine nickel atoms around which the coordination geometiys are distouted octahedrons.