Synthesis, spectroscopic study and crystal structure of bis(4,6-dimethyl-2-thiopyrimidinium) tetrachlorozincatum(II) monohydrate and its solid state transformations

Article abstract of DOI:10.1016/0020-1693(95)04634-L

The solid complex [H2L]2[ZnCl4]*H2O (HL=4,6-dimethyl-2-thiopyrimidine) has been obtained and characterized by IR, (1)H and (13)C NMR spectroscopies and thermal techniques. The molecular structure of this complex hasbeen established by single crystal X-ray diffraction. Crystals of the compound are orthorhombic, of space group P212121 with cell constants a=7.153(2), b=14.624(3), c=20.499(4)?, Z=6 and D(c)=1.572 g*cm**-3. Thestructure was solved and refined to R=0.049 (R(w)=0.029). The asymmetric complex unit consists of two 4,6-dimethyl-2-thiopyrimidinium cations, a [ZnCl4](2-) anion and a water molecule. The Zn(II) centres are tetracoordinated by chloride ions giving a tetrahedral arrangement. This asymmetric unit is stacked along the b axis giving rise to a packing of pyrimidine rings and [ZnCl4](2-) anions which are linked by hydrogen bonds involving chlorine atoms, NH groups and water molecules. The thermal treatment of [H2L]2[ZnCl4]*H2O leads to two different solid complexes [Zn(HL)2Cl2] and [ZnL2] which have been previously obtained and characterized byus.