Structure determination of three furan-substituted benzimidazoles and calculation of π–π and C—H...π inter­action energies

The structures of 2-(furan-2-yl)-1-(furan-2-ylmeth­yl)-1H-benzimidazole, its hydro­chloride monohydrate, and the hydro­bromide salt of 5,6-dimethyl-2-(furan-2-yl)-1-(furan-2-ylmeth­yl)-1H-benzimidazole exhibit a combination of π–π and C—H...π inter­molecular inter­actions. DFT calculations were used to estimate the strength of these inter­actions.