A mixture of N-(3-fluoro-4-morpholinophenyl)-4-(3-fluorophenoxy)-3-oxobutanamide (510 mg, 1.31 mmol), acetamide (154 mg, 2.61 mmol) and titanium tetraisopropanolate (3.2 mL) in xylene (10 mL) was stirred at 165° C. for 24 h. The mixture was cooled to rt and 60 mL of toluene and 60 mL of saturated NH4Cl aqueous solution were added. The resulting mixture was stirred at rt overnight. The mixture was then filtered and the filtrate was extracted with DCM (20 mL×4). The combined organic phases were washed with brine (30 mL×2), dried over anhydrous Na2SO4 and concentrated in vacuo. The residue was purified by a silica gel column chromatography (PE/EtOAc (V/V)=1:1) to give the title compound as a yellow solid (0.09 g, 17%). The compound was characterized by the following spectroscopic data:
