TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The imine group-containing compound of formula (II) is processed with concentrated sulfuric acid, concentrated hydrochloric acid, acetic acid and/or Lewis acid e.g. zinc chloride or anhydrous sodium acetate, anhydrous potassium acetate, sodium hydroxide, potassium hydroxide, ammonium chloride and/or ammonium acetate, to obtain benzopyrrole(3,2-b)carbazole of formula (IV). The benzopyrrole(3,2-b)carbazole (IV) is processed with strongly alkaline reaction conditions using reagent comprising sodium hydride, sodium hydroxide, sodium carbonate, potassium hydride, potassium hydroxide and/or potassium carbonate, to obtain benzopyrrole(3,2-b)carbazole of formula (V). The glacial acetic acid, concentrated sulfuric acid, anhydrous sodium acetate and phenylhydrazine derivative are reacted at 50-60 degrees C for 10 minutes, to obtain crude product of 2,8-dihalo-5,11-dihydro-indol-(3,2-b)carbazole or 2,8-dihalo-5,11-dihydro-indol-(3,2-b)carbazole is prepared by dissolving bromophenyl hydrazine hydrochloride salt in aqueous solution of sodium acetate in ethanol under nitrogen atmosphere, to obtain 1,4-diphenyl hydrazine cyclohexanone derivative in a heated reactor, adding solution of 1,4-diphenyl hydrazine cyclohexanone derivative to concentrated sulfuric acid/acetic acid/sodium acetate buffer solution with stirring and adding deionized water to quench, to obtain crude product of 2,8-dihalo-5,11-dihydro-indol-(3,2-b)carbazole, adding crude product of 2,8-dihalo-5,11-dihydro-indol-(3,2-b)carbazole to anhydrous methanol, slowly heating to reflux for 2-4 hours, filtering at 40-50 degrees C, and filtering, to obtain pure product of 2,8-dihalo-5,11-dihydro-indol-(3,2-b)carbazole, adding pure product of 2,8-dihalo-5,11-dihydro-indol-(3,2-b)carbazole to strong alkaline solution, processing at room temperature, adding sodium hydride reagent chosen from sodium hydroxide and sodium carbonate, potassium hydride, potassium hydroxide, potassium-N,N-dimethylformamide or dimethylsulfoxide, and reacting for 10-48 hours, catalyzing 2,8-dihalo-5,11-dihydro-indol-(3,2-b)carbazole under nitrogen atmosphere and adding aliphatic acid, 1,1'-bis(diphenylphosphino)ferrocene palladium chloride and methylene chloride. The crude product is filtered to remove impurities and washed with hot anhydrous methanol or ethanol, to obtain benzopyrrole(3,2-b)carbazole (I). The 2,8-dihalo-5,11-dihydro-indol-(3,2-b)carbazole, strong alkaline agent, sodium hydride, sodium hydroxide, sodium carbonate, potassium hydride, potassium hydroxide and/or potassium carbonate and alkyl halide are reacted for 24-48 hours, to obtain benzopyrrole(3,2-b)carbazole (IV).R'=1-32C saturated alkyl;andX=chloro, bromo or iodo.