Synthesis, spectroscopic and structural characterization of charge transfer complexes of 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8,8,8]hexacosane with iodine, TCNE and TCNQ

The charge transfer interaction of the interesting mixed nitrogen–oxygen donor 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8,8,8]hexacosane (HODABCHC) with σ-electron acceptor iodine and π-acceptors tetracyanoethylene (TCNE) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) have been investigated spectrophotometrically in chloroform. FT-IR, thermal and elemental analysis measurements are performed for the solid CT-interaction products. The reaction stoichiometries were found to be 1:4, 1:6 and 1:3 donor:acceptor molar ratio for iodine, TCNE and TCNQ reaction systems, respectively. The obtained relatively high reaction stoichiometry values are expected due to the expected high electron donation of the donor (HODABCHC). It contains six oxygen and two nitrogen donor atoms. Accordingly, the formed charge transfer complexes could be formulated as [(HODABCHC)I]+I7-, [(HODABCHC)(TCNE)6] and [(HODABCHC)(TCNQ)3].

► Three new CT-complexes of the HODABCHC with several acceptors are obtained. ► These CT-complexes are characterized in solution and as solids. ► Factors affecting the CT-interactions are discussed.