Ionization constants, and ultraviolet and infrared spectra of 4(7)- and 5(6)-halogenated benzimidazoles was written by Rabiger, D. J.;Joullie, M. M.. And the article was included in Journal of the Chemical Society in 1964.Reference of 83741-35-9 This article mentions the following:
For a series of 4(7)- and 5(6)-halogenated benzimidazoles, the ionization constants show that for compounds with a halogen atom in either the 4(7)- or the 5(6)-position the basicity decreases in the order F > I > Cl > Br. Attempts were made to correlate the effect of substituents on the pKa values of benzimidazoles by means of the Hammett equation; no relation could be established for 5(6)-substituted compounds, presumably because of the tautomeric nature of the ring, but a satisfactory correlation was obtained for the 4(7)- halogenated benzimidazoles. The ultraviolet data indicate that the implied order of overall electron release for halogen atoms in both the 4(7)- and the 5(6)-position is I > Br > Cl > F. The infrared spectra of these halogenated benzimidazoles are discussed. In the experiment, the researchers used many compounds, for example, 4-Bromo-1H-benzoimidazole (cas: 83741-35-9Reference of 83741-35-9).
4-Bromo-1H-benzoimidazole (cas: 83741-35-9) belongs to imidazole derivatives. The solubility of imidazoles in ethers is lower than that in alcohols and decreases with increasing chain length of the ethers . In contrast, the solubility of benzimidazoles in alcohols (C3–C6) is higher than in water and generally decreases with a Imidazole based anticancer drug find applications in cancer chemotherapy. It is used as buffer component for purification of the histidine tagged recombinant proteins in immobilized metal-affinity chromatography (IMAC).Reference of 83741-35-9
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem