General procedure for the synthesis of 2-amino-1-methylimidazole from 1-methyl-2-nitro-1H-imidazole: To a stirred solution of 1-methyl-2-nitro-1H-imidazole (500 mg, 3.9 mmol) in acetic acid (15 mL) was added iron powder (1.34 g, 24 mmol). The reaction mixture was stirred at 80 °C overnight. Upon completion of the reaction, the mixture was filtered through a diatomaceous earth pad and the filtrate was concentrated under vacuum. The residue was purified by preparative high performance liquid chromatography (HPLC) using a C18 column with an elution gradient of 10% to 90% acetonitrile/water (containing 0.1% formic acid) solution to afford 2-amino-1-methylimidazole (66 mg, 17% yield) as a yellow solid.
