The 4-chloro-5,7-difluoro-3-methyl-2-(piperazin-1-yl)quinoline 2,2,2-trifluoroacetate (150 mg, 0.37 mmol), potassium carbonate (360 mg, 2.60 mmol) and methyl chloroformate (0.11 mL, 1.50 mmol) were added to acetone (3.0 mL). The slurry was heated in a microwave reactor at 80° C. for 3 h. The reaction mixture was concentrated and the residue was partitioned between water and EtOAc. The aqueous layer was extracted with EtOAc (2×50 mL). The combined organic layers were washed with brine (1×30 mL) and dried over MgSO4 to give methyl 4-(4-chloro-5,7-difluoro-3-methylquinolin-2-yl)piperazine-1-carboxylate. Mass Spectrum (ESI) m/e=356.2 (M+1).
