The invention relates to bifluorenylidene derivatives and their corresponding radical anions and radical-cations of the following general formula (II): wherein: Y = C=O and m is an integer =0, preferably m = 1, with the proviso that when m = 0, A = boranyl; A = H, OH, alogen, amino group, thiol group, alkyl, oxyalkyl, alkenyl, alkynyl, aryl, boranyl. The invention also relates to the method of synthesis of said compounds and to their use, in particular to their use as components of materials in the molecular electronics, spintronics and in the telecom fields.