Novel molecular metals composed of a [3]radialene type acceptor : 1,2-bis(p-benzoquino)-3-[2(dicyanomethylene)-2,5-selenoquino]cyclopropane derivative

Abstract A new acceptor, 1,2-bis(p-benzoquino)-3-[2-(dicyanomethylene)-2,5-selenoquino]cyclopropane derivative (DCNS-CP) has been efficiently synthesized by the reaction of a cyclopropenone derivative with selenienylmalononitle and subsequent oxidation. DCNS-CP proved to be a powerful acceptor and its anion radical and dianion are very thermodynamically stable. Single crystals of [TTF][DCNS-CP] and [TTT][DCNS-CP] complexes showed metallic temperature dependencies of the conductivities down to 182 and 80 K, recording σmax values of 500 and 760 Scm−1, respectively. These are a new class of metals based on a functionally different type of organic acceptor consisting of three electron-accepting groups in full conjugation.