2,3-Dihydro-1 H -imidazo[1,2- a ]benzimidazole in acetic acid, and its N 1-Me derivative in CHCl3, are brominated at position 6 with bromine. Less nucleophilic N 9-R derivatives do not enter into the reaction under these conditions, but, like their N 1-R isomers, they are quite effectively brominated by the KBrO3-HBr system, but at position 7, probably due to the transition of the reaction to the mode of bromination of protonated forms of substrates. N 1- and N 9-alkyl-6(7)-Br-2,3-dihydroimidazo[1,2- a ]benzimidazoles can also be obtained by N -alkylation of 6(7)-Br-2,3-dihydroimidazo[1,2- a ]benzimidazoles under neutral or basic conditions.