Synthesis, Characterization, Theoretical studies and Biological activities of bimetallic Complexes of new Schiff base thiadiazole derivative with some trivalent metal ions

Abstract

Tetrachloro [5-(5---phenyl-3---N-ethyl-2---thiazolene)imino-3-N-ethyl-2-thion-1,3,4- thiadiazole].tetanium(IV), of a new Schiff base{TiL}derived from[ tetra chloro (5- amino-3-N- ethyl – 2 -thione-1, 3 ,4 – thiadiazole).tetanium(IV)] and(3-N-ethyl- 2-one –1 ,3,4-thiadiazaole) have been prepared.The product was characterized by by (FT-IR) ,(UV-Vis) Spectroscopy and elemental analysis (C.H.N.S) . {TiL}has been used as a chelating ligand to prepare a number of metal complexes with[Cr(Ш), Fe(Ш) , Ru(Ш), Rh(Ш) and Au(Ш)] . The prepared complexes were isolated and characterized by using (FT-IR) and (UV-Vis) spectroscopy, elemental analysis (C.H.N.S), Flame atomic absorption technique, in addition to magnetic susceptibility and conductivity measurements. Molar ratio method measurement in solution gave comparable results with those obtained from solid state studies. The work also include a theoretical treatment of the formed complex in the gas phase, this was done using the Hyperchem-6 program for the Molecular mechanics and Semi-empirical calculations. The heat of formation (∆Hf°) , binding energy (∆EB ) and bond length (∆EL) for [ASN] , [TiA]and {TiL} ligand and their metal complexes were calculated by (PM3 and AMBER) methods at 298 K°. Furthermore the electrostatic potential of the free ligand{TiL} was calculated to investigate the reactive sites of the molecules .PM3 were used to evaluate the vibrational spectra and electronic spectra of the ligand{TiL} and it's metal complexes(A1-A5( then compare the theoretically calculated wave numbers with the experimental values by using the [ASN] and [TiA]as authentic compounds .The theoretically obtained frequencies agreed with those found experimentally, in addition the calculation helped to assign unambiguously the most diagnostic bands.