4-amino-6-methoxy-2-methylthiopyrimidine and Hg(II) system: Solution and solid state studies on metalated and N-coordinated species. Crystal structure of [Hg2(HL)2(μ-Cl)2Cl2]

Article abstract of DOI:10.1016/0020-1693(95)04969-X

The acid - base behaviour of the pyrimidine analogue 4-amino-6-methoxy-2-methylthiopyrimidine (HL) and the reactivity with Hg(II) ion have been studied by potentiometric methods at 25 °C and 0.1 M KCl ionic strength. By fixing the appropriate pH conditions, solid species with stoichiometries HgLCl·H₂O and Hg₂(HL)₂Cl₄ have been isolated. The spectroscopic study of the solids shows that HgLCl·H₂O is a C(5)-organomercurial species, whereas the structure of Hg₂(HL)₂Cl₄ has been determined by single crystal X-ray diffraction methods. Hg₂(HL)₂Cl₄ is a binuclear complex with two Hg(II) ions tetrahedrally coordinated by a terminal chloride ion, a HL molecule and two bridging chloride ions. The Hg(II) ion is coordinated to HL via the N(3) endocyclic atom.