Charge transfer complexes of Schiff bases derived from 2-aminobenzothiazole with some acidic and nonacidic acceptors

When Schiff bases derived from 2-aminobenzothiazole were reacted with di- and trinitrobenzene derivatives as acidic and nonacidic acceptors in the ratio of 1:1, stable coloured charge transfer complexes (CTC's) were obtained. The structure and stoichiometry of the CTC's were studied by elemental analysis.as well as by electronic absorption and infrared and nuclear magnetic resonance spectra. The CTC's derived from nonacidic acceptors were stabilized via intermolecular π–π* and n–π* transitions while those derived from acidic acceptors were formed by intermolecular π–π* transitions and a proton transfer stabilized by resonance. The ionization potentials of the Schiff bases and the electron affinities of the nitrobenzene derivatives were calculated.