A binuclear Cd(II) complex containing bridging pyrimidine-based ligands

摘要

In this work, a pyrimidine-based ligand, N'-(amino( pyrimidin-2-yl) methylene)pyrimidine-2-carbohydrazonamide hydrate (APPH center dot H2O), and its binuclear complex of cadmium, [Cd(mu-APPH)Br](2), 1, were prepared and identified by elemental analysis, FT-IR, H-1 NMR spectroscopy as well as single-crystal X-ray diffraction. X-ray structure analysis of 1 revealed octahedrally coordinated cadmium centers with a CdN4Br2 environment containing two bridging APPH ligands; each APPH ligand acts as an N 4-donor (N 2-donor toward each cadmium atom) and forms two five-membered chelate rings that are approximately perpendicular to each other. In the network of 1, the N-H center dot center dot center dot Br hydrogen bonds form motifs such as R-2(2) (12, 14), R-6(6) (24, 26, ..., 46). The crystal network is further stabilized by p-p stacking interactions between pyrimidine rings. The optimized structures of the ligand and complex were investigated along with their charge distribution patterns by density functional theory and natural bond orbital analysis, respectively.