Synthesis, Structure, and Properties of a Cyclopent[fg]acenaphthylene-1,2-bis(p-quinone methide)s Derivative. An Extended Pyracyloquinone

The extended-quinone derivative of cyclopent[fg]acenaphthylene-1,2-dione (pyracyloquinone) is first synthesized and characterized. An X-ray analysis exhibits the non-planar structure involving bent of two 3,5-di-tert-butyl-4-oxo-cyclohexadienylidene units, and bond alternation along the molecular periphery. The facile formation of trianion radical on cyclic voltammetry reflects high-electron affinity enhanced by antiaromatic character of the formed pyracylene moiety on the dianion state.