To a mixture of 4-chloro-N-[4-(methylsulfonyl)phenyl]benzenecarboximidamide (Example 1, Step 1) (700 mg, 2.24 mmol) and sodium bicarbonate (376 mg, 4.48 mmol) in isopropanol (30 mL), 4-chlorophenacyl bromide (1.05 g, 4.48 mmol) was added. After heating the reaction mixture at 80°-85° C. for 18 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 was chromatographed (silica gel, hexane/ethyl acetate, 6/4) to give 2,4-bis-(4-chlorophenyl)-1-[4-(methylsulfonyl)phenyl]-1H-imidazole (545 mg, 55%) as a pale yellow solid: mp 169°-171° C. Anal. Calc'd. for C22H16N2SO2Cl12 : C, 59.60, H, 3.64, N, 6.32, S, 7.23. Found: C, 59.86, H, 3.80, N, 6.10, S, 7.27.
