SPECTROSCOPIC STUDIES OF METAL-PYRIMIDINE COMPLEXES - CRYSTAL-STRUCTURES OF 4,6-DIMETHYL-2-THIOPYRIMIDINE COMPLEXES WITH ZN(II) AND CD(II)

The structures of Zn(DMTP)2Cl2 and Cd(DMTP)2Cl2 (DMTP = 4,6-dimethyl-2 -thio-pyrimidine), have been obtained by X-ray diffraction methods. Bo th compounds crystallize in the monoclinic system. Zn(DMTP)2Cl2 crysta ls are of the P2(1) space group, with a = 7.133(2), b = 16.315(8), c = 7.402(2) and beta = 92.48(2), V = 860.7 angstrom3, Z = 2, F(000) = 42 0 and Dm = 1.60 g cm-3. Cd(DMTP)2Cl2 crystals are of the P2(1)/c space group, with a = 13.197(3), b = 8.438(3), c = 15.862(5) and beta = 97. 30(2), V = 1752.0 angstrom3, Z = 4, F(000) = 912 and Dm = 1.75 g cm-3. The structures were refined anisotropically to R = 0.028 and R(w) = 0 .027 on the basis of 2178 observed reflections (Zn(DMTP)2Cl2 complex) and to R = 0.038 R(w) = 0.035 on the basis of 2687 observed reflection s (Cd(DMTP)2Cl2 complex). The structures contain individual Zn(DMTP)2C l2 and Cd(DMTP)2Cl2 distorted tetrahedral units in which DMTP molecule s are S-bonded as monodentates to the corresponding metal ions; chlori de ions are also coordinated. On the basis of the crystallographic dat a of the above complexes, different coordination patterns of DMTP with several metal ions were established in a set of DMTP complexes (Hg(DM TP)Cl2,Pd(DMTP)2Cl2, Pt(DMTP)2Cl2 and Au(DMTP)Cl3 by a study of their ir, H-1 and C-13 NMR spectra.