Synthesis, molecular and electronic structures of half-sandwich ruthenium(II) complexes with pyrimidine-based ligands

The complexes [(C6H6)RuCl2(Hmtp)] and [(C6H6)RuCl2(C4H4N2)] have been prepared and studied by IR, 1H NMR, UV–VIS spectroscopy and X-ray crystallography. The complexes were prepared by reactions of [(C6H6)RuCl2]2 with 7-hydroxy-5-methyl[1,2,4]triazolo[1,5-a]pyrimidine (Hmtp) and pyrimidine, respectively, in methanol. The electronic structures and UV–Vis spectra of the complexes have been calculated using the TD–DFT method.