In this doctoral thesis, iodotrimethylplatinum(IV) complexes of different pyridine and 2,2´ bipyridine ligands are investigated. The crystal structures of both the mononuclear and dinuclear pyridine complexes reveal an octahedral coordination around the platinum(IV) and a facial arrangement of the methyl groups. The crystal structure of the dinuclear complexes confirms that the iodide ligand acts as a bridging ligand that holds the two platinum metal ions together.The reaction of the mononuclear pyridine complexes with iodotrimethylplatinum(IV) in chloroform results in the formation of the corresponding dinuclear complexes (both cis and trans isomers) of pyridines. Although the pyridine substituents have no significant influence on the crystal structures of either the mononuclear or the dinuclear complexes, the equilibrium population of these complexes in solution depends largely on the electronic effect of the pyridine substituent as well as on the steric bulk of the pyridine substituent. Iodotrimethylplatinum(IV) on treatment with 2,2´-bipyridine and its derivatives gives mono-nuclear 2,2´-bipyridine complexes. The crystal structure of the bipyridine complexes confirms the fac-octahedral coordination of the trimethylplatinum moiety and the bidentate coordination of the 2,2´-bipyridines. Bond length comparison shows that Pt-N bond distances in bipyridine complexes are slightly shorter than in the corresponding pyridine complexes, reflecting the better pi-acceptor character of the 2,2´-bipyridines. In addition, the N-Pt-N bite angle in the bipyridine complexes is much lower than in the pyridine complexes. It was also observed that in the crystal packing of 4,4´-Dichloro-2,2´-bipyridine complex of iodotrimethylplatinum(IV), intermolecular non-covalent interaction between methyl hydrogen and chlorine atom leads to the formation of zig-zag chain structures, which are linked through weak pi-pi interactions to form two-dimensional layer structure.The reaction of iodotrimethylplatinum(IV) complexes of pyridines with the corresponding 2,2´-bipyridines lead to the substitution of ligands resulting in the formation of chelate bipyridine complexes. The equilibrium for these substitution reactions strongly favours the formation of chelate products. The formation of chelate complexes in solution at equilibrium depends largely on the electronic effect of the substituent as well as on the nature of the solvent.
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