A mixture of (E)-4-(4-(trifluoromethyl)benzylideneamino)isobenzofuran-1(3H)-one (1 g, 3.28 mmol) and N-methyl-2-imidazolecarbaldehyde (400 mg, 3.61 mmol) in ethyl propionate (40 mL) was cooled to 0° C. Then a solution of sodium ethoxide in ethanol (sodium (31 mg, 13.1 mmol) in ethanol (10 mL)) was added dropwise. After the addition, the mixture was stirred at room temperature for 2 hr. The mixture was quenched with water (10 mL) and solvent was removed in vacuum. The residue was dissolved in water, and then extracted with ethyl acetate (100 mL×4). The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, and concentrated to give crude product. The crude product was purified by chromatography (silica gel, petroleum ether/ethyl acetate=1:1) to give the title compound (150 mg, yield 8%). LC-MS (ESI) m/z: 444 (M+1)+.
