p-Toluenesulfonic acid → 6-Bromo-1-methyl-1H-benzimidazole

Participants

Reaction Conditions

Reaction Steps

To a solution of 5-bromo-N1-methylbenzene-1,2-diamine (7.4 g, 37 mmol) in trimethyl orthoformate (100 mL) was added p-toluenesulfonic acid (0.36 g, 1.9 mmol). The reaction mixture was heated at 100° C. for 4 h, cooled, concentrated, dissolved in ethyl acetate, washed with brine, dried over sodium sulfate and concentrated. The crude product was used in next step without further purification. (7.3 g, yield 93%) MS (ESI+) e/z: 212.1.

Provenance & Evidence