6-Chloro-2,3-diaminotoluene is a white solid powder at room temperature and pressure, with significant alkalinity and strong nucleophilicity. Due to the presence of two amino units in the ortho position of the benzene ring, it can undergo condensation reactions with aldehydes to prepare corresponding benzimidazole derivatives. This reaction is widely used to prepare benzimidazole drugs and bioactive molecules. It is an intermediate in organic synthesis and medicinal chemistry, such as Nemonapride.
A solution of 3-chloro-2-methyl-6-nitroaniline in a mixture of acetic acid and water was heated to 90 C, to which iron powder was added. The resulting reaction mixture was further heated at 90 C for 2 hours. At the end of the reaction the reaction mixture was cooled to room temperature and poured into ice, then the pH was adjusted to 8 and ethyl acetate was added to the reaction mixture. The resulting mixture was filtered and the organic phase was separated, the resulting organic layer was dried with anhydrous sodium sulfate, filtered to remove the desiccant and the resulting filtrate was concentrated under vacuum. The resulting residue was purified by column chromatography on silica gel, eluting with pentane:ethyl acetate to give 6-chloro-2,3-diaminotoluene.
