TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): The preparation of (I) comprises: taking 2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-fluorene compound of formula (II), anthracene compound of formula (III) and 4H-thieno(3',2':4,5)cyclopenta(1,2-b)thiophene compound of formula (IV) as raw materials; and subjecting to Suzuki reaction in a solvent under anaerobic condition in the presence of an alkali and a catalytic agent system. Preferred Method: The compound (II) is prepared by taking the 2,7-dibromo-9H-fluorene compound of formula (V), 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (VI) or 4,4,4',4',5,5,5',5'-octamethyl-2,2'-bi(1,3,2-dioxaborolane) (VII) as raw materials; adding the compound (V) and n-butyllithium to the solvent in a mol ratio of 1:2-1:4 in anaerobic aqueous reaction condition, adding (VI) or (VII), reacting, where the molar weight of (VI) or (VII) is 2-4 times of that of the compound (V), heating to room temperature and reacting for 12-48 hours, where the solvent is tetrahydrofuran, diethyl ether, dichloromethane, chloroform or ethyl acetate.X=I or Br.Preferred Components: The reaction temperature of the Suzuki reaction is 70-100 degrees C. The reaction time is 24-72 hours. The catalytic agent is tetrakis(triphenylphosphine)palladium(0), palladium(II) acetate, tricyclohexyl phosphine, tris(dibenzylideneacetone)dipalladium(0)/tri(o-tolyl)phosphine or bis(triphenylphosphine)palladium chloride. The alkali is aqueous sodium hydroxide solution, aqueous sodium carbonate solution, aqueous sodium bicarbonate solution or aqueous tetraethylammonium hydroxide solution. The solvent is benzene, chlorobenzene, toluene, ethylene glycol dimethyl ether, tetrahydrofuran, diethyl ether, dichloromethane, chloroform or ethyl acetate. The using amount the catalytic agent is 0.05%-20% of molecular weight of compound (II). The using amount of alkali is 2-20 times the molecular weight of the compound (II). Preferred Definitions:    Either m=8;    x=0.1 or 0.5;    R 1, R 2=H; and    R 3=straight-chain hexyl; or    m=6;    x=0.2 or 0.8;    R 1, R 2=2-octyl decyl; and    R 3=straight-chain octyl; or    m=12;    x=0.5 or 0.6;    R 1=F;    R 2=H; and    R 3=2-ethyl hexyl; or    m=10;    x=0.4 or 0.5;    R 1=1,4-dimethoxy;    R 2=H; and    R 3=dodecyl; and    n=10-50.