952511-48-7

64-18-6

952511-74-9

952511-48-7

3. A mixture of 4-bromo-3-methylbenzene-1,2-diamine (28 g, 140 mmol), formic acid (240 mL), and 37% hydrochloric acid (400 mL) was heated to 60 °C and held for 12 h. The reaction was completed by filtration. Upon completion of the reaction, the mixture was cooled in an ice-water bath and the pH was slowly adjusted to 8-9 with 28% ammonia. the resulting solid was collected by filtration, washed with water, and dried in air to afford 5-bromo-4-methyl-1H-benzo[d]imidazole (25 g, 98% yield) as a yellow solid. Mass spectrum (ESI) m/z = 213 [M + 1]+.