Molecular Complexes of Tetracyanoethylene (TCNE) With Drugs

P. Veera Somaiah*, R. Ashok Reddy and G. Venkateshwarlu

Department of Chemistry, Nizam College, Osmania University, Hyderabad - 500 001 (India)

Molecular complexes of TCNE with some antibiotic drugs have been studied spectrophotometrically in chloroform. All the complexes exhibited charge transfer band(s) in the visible region where neither donor nor acceptor have any absorption. The stoichiometry of the each of the complexes is found to be 1:1 and is unaffected by variation of temperature. The complexes are sterically unhindered and indicates that the interaction is of the p ® p* type. The ionization potentials of the donors have been evaluated from the energies of CT bands. The stabilities and thermodynamic parameters of the complexes have been determined from the absorption studies on the CT bands. The variation of position of CT bands and the stabilities of the complexes have been correlated with the structures of the drugs.

TCNE; antibiotic drugs; molecular complexes; absorbance, lmax; oscillatory strength; transition dipolemoments