A suspension of N-(6-hydroxy-1,3-benzothiazol-2-yl)cyclopropanecarboxamide (1.17 g, 5.00 mmol), 1,2-difluoro-4-nitrobenzene (0.96 g, 6.00 mmol) and cesium carbonate (3.26 g, 10.0 mmol) in dimethyl sulfoxide (10 mL) was stirred at 50° C. for 5 hr. After cooling to room temperature, water was added to the reaction mixture, and the mixture was extracted 3 times with ethyl acetate/tetrahydrofuran. The organic layer was washed with water, dried over anhydrous sodium sulfate and filtered. The solvent was evaporated under reduced pressure, and the residue was washed with ethyl acetate and collected by filtration to give the title compound (1.22 g, 65%) as a pale-yellow solid.
