To a mixture of 4-chloro-N-[4-(methylsulfonyl)phenyl]benzenecarboximidamide (Example 1, Step 1) (400 mg, 1.29 mmol) and sodium bicarbonate (216 mg, 2.59 mmol) in isopropanol (25 mL), 2-chloro-4′-fluoroacetophenone (670 mg, 3.87 mmol) was added. After heating the reaction mixture at 80-85° C. for 48 hours, the solvent was removed. The residue was redissolved in methylene chloride and washed with aqueous sodium bicarbonate and water. The organic fractions were combined, dried over sodium sulfate, filtered and concentrated in vacuo. The crude product (800 mg) was purified by chromatography (silica gel, hexane/ethyl acetate, 1/1) to give 2-(4-chlorophenyl)-4-(4-fluorophenyl)-1-[4-(methylsulfonyl)phenyl]-1H-imidazole (200 mg, 36%) as a pale yellow solid: mp (DSC) 180° C. Anal. Calc'd. for C22H16N2SO2FCl: C, 61.90, H, 3.78, N, 6.56, S, 7.51. Found: C, 61.92, H, 3.74, N, 6.43, S, 7.62.
