TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): Preparation of the bifluorenylidene derivatives (II) involves: i) synthesizing a di-substituted fluorene in position 2 and 7; ii) adding an halogen imide to the reaction mixture containing the di-substituted fluorene synthesized in step (i), preferably N-bromosuccinimide and irradiating with UV light; and iii) treating the compound obtained in step (ii) with alkaline or alkaline earth metals in an anhydrous environment. The electrochemical method for synthesizing the radical anions of the derivatives (II) involves adding the neutral compound (II) into radical anions at a concentration of 0.01 M and 1 mM (preferably 0.01 M and 0.5 mM, especially 1 mM), to an anhydrous aprotic solvent containing a supporting electrolyte, also anhydrous, to obtain a concentration of the latter 1-0.01 (preferably 0.2-0.05, especially 0.1) M followed by placing in an electrolytic cell and applying a voltage between the electrodes to obtain the required radical anion. Preferred Definitions:    A'=H, chlorine, alkyl, aryl, hydroxy, mercapto, amino, fluoroaryl, chloroaryl, nitroaryl, aminoaryl, alkoxyaryl, alkylaryl, N-alkylcarbazolyl, biphenylenyl, hydroxyaryl, mercaptoaryl, fluorenone-2-yl, alkyloxy, cyanoaryl, N(alkyl)2, alkynyl, alkenyl, cyclopentadienonyl, furanyl, thiophenyl, B(OH)2 or 4,4,5,5-tetramethyl-1,3,2-dioxaborolan.    SPECIFIC COMPOUNDS - 2 Compounds i.e. 2,7,2',7'-Tetrakis-dihydroxyboranyl-(9,9')bifluorenylidene (IA); and phenyl-(7,2',7'-tribenzoyl-(9,9')bifluorenyliden-2-yl)-methanone are disclosed as the compound (II).    EXAMPLE - In a flask triethylamine (25 mmol), 2,2',7,7'-tetrabromobifluorenylidene (5 mmol) and tetrahydrofuran (THF) (3 ml) were placed together. The septum was substituted with a reflux condenser while palladium was added (0.5 mmol). Finally, to the reaction mixture di-isopropylaminoborane was added with a syringe (15 ml, 1M solution in THF). The reaction mixture was then heated under reflux at 65 degrees C. After work up, 2,7,2',7'-Tetrakis-dihydroxyboranyl-(9,9')bifluorenylidene was obtained.