Study On Synthesis, Structure And Properties Of Thiourea Derivatives And Its Metal Complex

Thiourea and its derivatives have received increasing attention for a long timedue to their broad usages. Recently, it is revealed that thiourea derivatives exhibit wide ranging biological activities, which including anticancer, antiviral and antibacterial, etc. Relying on the good chelate ability, thiourea and its derivatives also could be used in the extraction of trace metal and the separation of platinum group metals, and may be applied in the anion acceptor recognition. Moreover, they are wildly used in nonlinear material. Thiourea derivatives also act as common corrosion inhibitors.In order to further explore the relationship between structure and activity of the thiourea derivatives, the following novel compounds containing thiourea unit are synthesized, and single crystal is obtained. Their chemical formulates are listed as below. (I):(C8H9N3O2S)2?H2O (II):(C9H10N3O2S)2?H2O (III):(C10H12N3O2S)2?H2O (IV):Ni(C10H12N3O2S)2?H2O(I) belongs to carbonyl thiourea, while (II) and (III) are thiosemicarbazonesand(IV) is nickel complex of thiosemicarbazone. The characterization and properties(X-ray, UV-vis, IR, UV-VIS solid diffusion electronic spectrum, fluorescent spec- trum and molar conductance) of the compounds are described. At the same time,the electronic structure and bonding properties of the compounds by quantum chemistry calculation are also discussed.We conformed the crystal structures of the four compounds by X-ray diffract-tion. The results show that all of the ligands are composed of two independent substitutional thiourea molecules and one water molecular. Water molecules are found inside all the compounds, which is unwonted within thiourea derivatives. Abundant hydrogen bonds network among the compound molecules and water help stabilize the crystal structures. (III) exists strongπ-πaromatic stacking interaction. NiII ion, which is located on an inversion center, is tetracordinated and surrounded by the two ligands acting as bi-dentate through the Sand N atoms, and the coordination results in a square planar configuration in (IV).Quantum chemistry calculation shows that H bonds signify the stability of the crystal structures.