TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The preparation of (II) comprises: (a) reacting 1,4-dibromo-2,5-diiodo-benzene (3-bromo-thiophen-2-yl)-trimethyl-stannane in molar ratio of 1:1-1:1.5 under inert atmosphere in presence of second catalyst, chloride and solvent at room temperature for 1-2 hours and heating at 50-55 degrees C for 3-4 hours, then cooling the reaction mixture to room temperature to obtain 3-bromo-2-(2,5-dibromo-4-(3-bromothien-2-yl)phenyl)thiophene; (b) mixing 3-bromo-2-(2,5-dibromo-4-(3-bromothien-2-yl)phenyl)thiophene and alkyl amine in a molar ratio of 1:3-1:4 under inert atmosphere, then adding solvent, sodium tert-butoxide, 2,2'-bis(diphenylphosphino)-1,1-binaphthyl and third catalyst and then refluxing to perform Buchwald-Hartwig amination for 2-3 hours, then cooling to room temperature, filtering to remove solids, extracting the resultant filtrate, washing with water and saturated brine, drying, filtering, removing the solvent by rotary evaporation and then purifying by silica gel column chromatography to obtain 5,14-dithia-9,18-diazapentacyclo(10.6.0.0(3,10).0(4,8).0(13,17))octadeca-1,3(10),4(8),6,11,13(17),15-heptaene derivative of formula (IV); and (c) mixing (IV) and N-bromosuccinimide in a solvent to form a solution, cooling to -78 degrees C and then dropwisely adding N-bromosuccinimide by using pressure-equalizing dropping funnel, where the molar ratio of (IV) and N-bromosuccinimide is 1:2.2-1:3, then stirring, reacting for 0.5-1 hour and then quenching the reaction with water, extracting the reaction solution, drying and purifying by silica gel column chromatography to obtain (II). Preferred Components: The organic solvent is tetrahydrofuran, N,N-dimethylformamide or toluene. The first catalyst is mixture of tris(dibenzylideneacetone)dipalladium(0) and tri(o-tolyl)phosphine, bis(triphenylphosphine)palladium dichloride, or tetrakis(triphenylphosphine)palladium(0). The amount of first catalyst is 0.01-5 mole% of (II). The molar ratio of tris(dibenzylideneacetone)dipalladium(0) and tri(o-tolyl)phosphine is 1:2-1:20. In the preparation of (II): the solvent used in step (a) is tetrahydrofuran, N, N- dimethylformamide or toluene; the chloride is lithium chloride or cuprous chloride; the second catalyst is bis(triphenylphosphine)palladium dichloride or tetrakis(triphenylphosphine)palladium(0); the solvent used in step (b) is xylene or toluene; the third catalyst is bis(triphenylphosphine)palladium dichloride, tris(dibenzylideneacetone)dipalladium(0) or tetrakis(triphenylphosphine)palladium(0); the solvent used in step (c) is tetrahydrofuran and/or N,N-dimethylformamide; the molar ratio of chloride and 1,4-dibromo-2,5-diiodo-benzene is 1.5:1-1.62:1; the mole ratio of second catalyst and 1,4-dibromo-2,5-diiodo-benzene is 0.01-5; the molar ratio of sodium tert-butoxide and 3-bromo-2-(2,5-dibromo-4-(3-bromothien-2-yl)phenyl)thiophene is 5-8; the molar ratio of 2,2'-bis (diphenylphosphino)-1,1-binaphthyl and 3-bromo-2-(2,5-dibromo-4-(3-bromothien-2-yl)phenyl)thiophene is 0.2-0.3; and the molar ratio of third catalyst and 3-bromo-2-(2,5-dibromo-4-(3-bromothien-2-yl)phenyl)thiophene is 5-10%.    TECHNOLOGY FOCUS - POLYMERS - Preparation (Claimed): The preparation of (I) comprises: performing Stille coupling reaction of 6,15-dibromo-5,14-dithia-9,18-diazapentacyclo(10.6.0.0(3,10).0(4,8).0(13,17))octadeca-1,3(10),4(8),6,11,13(17),15-heptaene compounds of formula (II) and 5,8-bis-(5-trimethylstannanyl-thiophen-2-yl)-2,6,7-trithia-1,3-diaza-trindene compounds of formula (III) in a molar ratio of 1:1-1:15 in presence of organic solvent containing first catalyst at 60-1320 degrees C under inert gas atmosphere for 24-72 hours and then separating and purifying. Preferred Method: The separation and purification step comprises removing excess toluene of reaction mixture by vacuum distillation, precipitating with methanol, filtering, washing with methanol, drying and carrying out alumina column chromatography, eluting with chloroform to obtain liquid, distilling to remove the solvent, recrystallizing from methanol, extracting the resultant solid with acetone in Soxhlet extractor for 3 days, precipitating with methanol and then filtering under vacuum for overnight. Preferred Definitions:    R1 = CH2-CH(C4H9)-C10H21, C6H13, CH3 or C8H17;    R2 = H, C6H13 or C16H33; and    R3 = H or CH3.