Electronic Structural Characterization of Cycloheptadienequinone and Cyclopentenequinone Systems on the Models of 2,3,4,5-Dibenzo-7,8-diphenylheptatriafulvalene-1,6-quinone and 5,6-Diphenylcalicene-1,4-quinone

Abstract The title heptatriafulvalene- and calicene-quinones have been synthesized. The difference in the degree of the charge separation between these quinones has been ascribed to the increasing contribution of pseudo 6π and 4π electron peripheries in the 7- and 5-membered rings to the respective polarized canonical structures.