Tert-butyl 6-fluoroquinolin-3-ylcarbamate (1.3 g, 4.95 mmol) was used as starting material, which was dissolved in 1,2-dichloroethane (15 mL), followed by trifluoroacetic acid (15 mL) and water (1 mL). The reaction mixture was stirred at room temperature for 6 hours. Upon completion of the reaction, the solvent was removed by vacuum evaporation and the residue was ground with ether. The resulting solid was purified by fast chromatography with the eluent being a 2N ammonia methanol solution in dichloromethane (gradient: 0% to 3%) to afford 6-chloroquinolin-2-amine as a colorless solid in a yield of 0.47 g (59% yield). Mass spectrometry (MS) analysis showed m/z 162.9 (MH+).
