TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): Preparation of benzofuran derivative (I) involves placing furan-3-carboxylic acid (10-20 parts) in dichloromethane (50-80 parts), dripping oxalyl chloride (20-40 parts) slowly, cooling the mixture by ice-water bath, stirring the mixture for 20-24 hours at room temperature, evaporating the mixture to remove the solvent and non-reacted oxalyl chloride monomer to obtain furan-3-carbonyl chloride, mixing diethylamine (20-40 parts) and dichloromethane (80-120 parts), dripping furan-3-carbonyl chloride (10-20 parts) slowly, cooling the mixture by icewater bath, stirring the mixture for 0.5-1 hours at room temperature, washing and extracting the mixture by de-ionized water (200-300 parts), drying the organic component by anhydrous magnesium sulfate, filtered and condensed the organic component to obtain the crude product, distilling the pure N,N-diethylfuran-3-amide, injecting n-butyl lithium (10-20 parts) and diisopropylidene acetone into dried diethyl ether solution (80-100 parts), stirring the solution at 0 degrees C for 10-20 minutes to form lithium diisopropylamide (LDA) solution, dissolving 10-20 parts of N,N-diethylfuran-3-amide into 50-60 parts of dried ethyl ether solution, injecting the solution into LDA solution slowly, reflowing the solution for 4-6 hours, pouring the crude product into the de-ionized water, extracting the solution by dichloromethane, drying, filtering and condensing the solution by anhydrous magnesium sulfate, recrystallizing the solution by glacial acetic acid, drying the product at vacuum to obtain benzo-(1,2b4,5b')difuran-4,8-ketone, mixing 10-20 parts of benzo-(1,2b-4,5b')difuran-4,8-ketone, 25-50 parts of zinc powder, 15-30 parts of sodium hydroxide and 50-80 parts of de-ionized water, heating and reflowing the mixture for 1-2 hours, adding 20-40 parts of halogen alkane and tetrabutyl ammonium bromide into the reaction system, reflowing the mixture for 6-8 hours, pouring the crude product into 300-400 parts of de-ionized water, washing and filtering the mixture to remove the solid matter and the non-reacted monomer, adding a plenty of water and ethyl ether, washing and extracting the mixture, collecting the organic phase, drying the organic phase by anhydrous magnesium sulfate to obtain pure 4,8-di(R-oxygen)benzo-(1,2b-4,5b')difuran derivative of formula (II), mixing 10-20 parts of 4,8-di(R-oxygen)benzo-(1,2b-4,5b')difuran derivative and 100-150 parts of dichloromethane completely, injecting 50-80 parts of dichloromethane solution into 20-40 parts of elemental bromine, reacting the mixture for 6-10 hours at room temperature, pouring 2-5 mole/l of sodium thiosulfate solution to remove the non-reacted elemental bromine, washing, extracting, filtering, condensing and drying the mixture by 200-300 parts of de-ionized water and dichloromethane to obtain the pure 2,6-dibromine-4,8-di(R-oxygen)benzo(1, 2b-4,5b')difuran derivative of formula (III), dissolving 10-20 parts of the derivative (III) into 100-150 parts of dried tetrahydrofuran, cooling the system to -78 degrees C, dripping 20-25 parts of n-butyl through one end, stirring the mixture for 1-2 hours, adding 20-25 parts of trimethyltin chloride to cooling bath, stirring the mixture for 2-3 hours, pouring the reactant into 200-300 parts of de-ionized water, drying, filtering and condensing the organic component by magnesium sulfate to obtain pure 2,6-di(tintrimethyl)-4,8-di(R-oxygen)benzo(1, 2b-4,5b')difuran derivative of formula (IV), dissolving 10-20 parts of the derivative (IV) and 10-20 parts of halogen aryl or halogen heteroaryl derivative into 300-500 parts of dried methylbenzene solution, adding 2-5% of tetrakis(triphenylphosphine)palladium to the system, stirring the mixture at 110 degrees C for 16-24 hours, reducing the temperature to room temperature, pouring the reactant into 500-1000 parts of methanol, filtering the mixture, and condensing and drying the chloroform to obtain the pure solid product. Preferred Definitions:    R=methyl, ethyl, propyl, butyl, amyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, myristyl, pentadecane, hexadecyl, 2-ethylbutyl, 2-ethylhexyl, 2-ethyloctyl, 2-ethyldodecyl, 2-ethylhexadecyl, 2-trifluoroethylbutyl, 2-trifluoroethylhexyl, 2-trifluoroethyloctyl, 2-trifluoroethyldodecyl, 2-trifluoroethylhexadecyl, phenyl, naphthyl, methyl phenyl, ethyl phenyl, propyl phenyl, butyl phenyl, amyl phenyl, hexyl phenyl, heptyl phenyl, octyl phenyl, nonyl phenyl, decyl phenyl, undecyl phenyl, dodecyl phenyl, tridecyl phenyl, myristyl phenyl, pentadecane phenyl, hexadecyl phenyl, m-trifluoromethyl phenyl, para-trifluoromethyl phenyl, 3,5-trifluoromethyl phenyl or halo phenyl, preferably 2-ethylhexyl bromide, bromododecane, 2-2-trifluoroethyl hexyl bromide, m-trifluorobenzylene bromide, para-trifluorobenzylene bromide or 3,5-trifluorobenzylene bromide;and    R1=thiophene derivative, benzothiazole derivative, benzothiophene derivative, fluorine derivative or naphthalene derivative.