Syntheses of Benzoimidazole Derivatives Containing Carbazole Unit

Two series of novel benzoimidazole derivatives containing carbazole unit were synthesized via condensation-cyclization of N-alkylcarbazole-3-formaldehyde with 1,2-diaminobenzene in "one pot" reaction without catalyst. The effects of temperature, selection & amount of solvents and molar ratio of the two reagents on the reactions have been investigated; significantly, one of these two series of benzoimidazole derivatives could be prepared as the major products selectively by changing the molar ratio of the two reagents.