Spectroscopic studies of the reactions of pi-electron acceptors with the cyclic polyamine 1,4,8,11-tetraazacyclotetradecane

The reactions of pi-electron accepters such as 1-chloro-2,4,6-trinitrobenzene (picryl chloride), 7,7',8,8'-tetracyanoquinodimethane (TCNQ), tetrachloro-p-benzoquinone (chloranil) and tetracyanoethylene (TCNE) with the cyclic polyamine base 1,4,8,11-tetraazacyclotetradecane (TACTD) have been investigated in CHCl3 solvent. The data indicate the formation of the CT-complexes with the general formula {[}(TACTD) (acceptor)(2)]. The 1 : 2 stoichiometry of the (TACTD)-acceptor was based on elemental analysis and infrared spectra of the solid CT-complexes along with the photometric titration curves for the reactions in CHCl3. The formation constants (K) for the CT-complexes are shown to be strongly dependent on the type and structure of the pi-acceptor.