2,2′-Bipyridine Adduct of Bis(O,O′-di(2-phenylethyl)dithiophosphato)cadmium(II): Synthesis, Spectroscopic Characterization, Crystal Structure and Antibacterial Activity

A new 2,2'-bipyridine adduct of bis(O,O'-di(2-phenylethyl)dithiophosphato) cadmium(II), [Cd{S2P(OCH2CH2Ph)(2)}(2)center dot bipy] (1, bipy = 2,2'-bipridine), was synthesized and characterized by elemental analyses, IR. UV-vis, H-1 NMR, fluorescence spectroscopy, thermo-gravimetric analysis, and X-ray single-crystal diffraction. The crystal of 1 crystallizes in triclinic, space group P (1) over bar with a = 10.4607(19), b = 11.679(2), c = 18.480(3) angstrom, alpha = 98.900(2), beta = 103.321(2), gamma = 91.779(2)degrees, V= 2165.2(7) angstrom(3), D-c = 1.447 g/cm(3), Z = 2, C42H44O4N2P2S4Cd, M-r = 943.37, F(000) = 968, mu = 0.814 mm(-1), the final R = 0.0536 and wR = 0.1206 for 6275 observed reflections with I > 2 sigma(I) and R = 0.0690 and wR = 0.1339 for all data. The result shows that the Cd(1) centre is five-coordinated by two N and three S atoms in a highly distorted square pyramidal configuration. The C-H center dot center dot center dot S hydrogen bonding interactions and a set of weak intermolecular pi-pi stacking between adjacent aromatic rings stabilize the structure and make 1 assemble into a 1D zig-zag chain. In addition, the antibacterial activities of 1 against Escherichia coli, Bacillus subtilis and Staphylococcus bacteria were also screened by disc diffusion method.