TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (claimed): Compound (I) is prepared by reacting n-bromohexane solution with carbazole solution and potassium tert-butoxide at room temperature for 12-18 hours to obtain N-hexylcarbazole; adding phosphoryl chloride and dimethyl formamide; subjecting mixture to reflux heating for 24-36 hours to obtain 3-formyl-N-hexylcarbazole; reacting with N-bromosuccinimide and 3-methylthiophene solution to obtain 2,5-dibromo-3-methylthiophene; adding carbon tetrachloride, benzoyl peroxide and N-bromosuccinimide; subjecting mixture to reflux heating for 6-12 hours to obtain 2,5-dibromo-3-bromomethylthiophene; adding triethylphosphine oxide; subjecting mixture to reflux heating for 2-8 hours; adding organic solvent and potassium tert-butoxide; and reacting at room temperature for 0.5-1 hour. Preferred Components: The mole ratio of potassium tert-butoxide and carbazole is 2:1. The mole ratio of n-bromohexane and carbazole is 2:1. The mole ratio of phosphoryl chloride and N-hexylcarbazole is 3:1. The mole ratio of dimethyl formamide and N-hexylcarbazole is 1.05:1. The mole ratio of N-bromosuccinimide and 3-methylthiophene is 2.5:1. The mole ratio of benzoyl peroxide and 2,5-dibromo-3-methylthiophene is 0.1:1. The mole ratio of N-bromosuccinimide and 2,5-dibromo-3-methylthiophene is 1.1:1. The mole ratio of 2,5-dibromo-3-bromomethylthiophene and triethylphosphine oxide is 1:2.2-3. The mole ratio of 3-formyl-N-hexylcarbazole and phosphate is 1-1.2:1. The mole ratio of potassium tert-butoxide and phosphate is 2-3:1. The carbazole solution comprises carbazole and tetrahydrofuran, and having a concentration of 1-5 mol/l. The n-bromohexane solution comprises tetrahydrofuran and n-bromohexane, and having a concentration of 1-20 mol/l. The 3-methylthiophene solution comprises 3-methylthiophene (0.1-0.2 mol), chloroform (50 ml) and acetic acid (10 ml). The organic solvent comprises tetrahydrofuran, 3-formyl-N-hexylcarbazole and phosphate containing compound having a concentration of 0.1-5 mol/l. The mole ratio of 2,5-dibromothiophene reacts and butyl lithium is 2.2-2.5:1. The mole ratio of butyl tin trichloride and 2,5-dibromothiophene is 2.2-2.5:1. The mole ratio of (I) and 2,5-di(tributyl tin)thiophene is 1:1-1.1. The mole ratio of n-bromohexane and magnesium solution is 1:1.1. The mole ratio of 1,3-bromothiophene and n-bromohexane is 1.2:1. The mole ratio of nickel diphenylphosphinoferrocene dichloride and n-bromohexane is 0.005:1. The mole ratio of N-bromosuccinimide and 3-hexylthiophene is 2.5:1. The mol ratio of butyl lithium and 2,5-dibromothiophene is 2.2-2.5:1. The mole ratio of butyl tin trichloride and 2,5-dibromothiophene is 2.2-2.5:1.