p-Toluenesulfonic acid monohydrate → 1h-Imidazole,2-(3-chloro-4-methylphenyl)-1-[4-(methylsulfonyl)phenyl]-4-(trifluoromethyl)-

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Reaction Steps

A mixture of 2-(3-chloro-4-methylphenyl)-4-hydroxy-1-[4-(methylsulfonyl)phenyl]-4-(trifluoromethyl)-4,5-dihydro-1H-imidazole from Step 2 (725 mg, 1.7 mmol) and p-toluenesulfonic acid monohydrate (150 mg) in toluene (40 mL) was heated to reflux for 48 hours. The reaction mixture was cooled and the solvent removed under reduced pressure. The crude residue was redissolved in methylene chloride and washed with water, aqueous sodium bicarbonate and brine. After drying (Na2SO4), filtration and concentration in vacuo, the crude mixture (860 mg) was purified by chromatography on silica gel using toluene/ethyl acetate 1/1 to give pure 2-(3-chloro-4-methylphenyl)-1-[4-(methylsulfonyl)phenyl]-4-(trifluoromethyl)-1H-imidazole (660 mg, 95%) as a white solid: mp(DSC) 206° C. Anal. Calc'd. for C18H14N2SO2F3Cl: C, 52.12; H, 3.40; N, 6.75; S, 7.73. Found: C, 52.24; H, 3.45; N, 6.64; S, 7.83.

Provenance & Evidence