反应详情

In a manner similar to Example 4, Step (b), 4-oxo-4-(4′-trifluoromethyl-biphenyl-4-yl)-butyric acid, methyl ester (1.34 g, 0.00398 mol) was refluxed in 6 M aqueous hydrochloric acid (24 mL) to give 1.27 g of 4-oxo-4-(4′-trifluoromethyl-biphenyl-4-yl)-butyric acid as an 80% pure solid. A portion (0.059 g) of the material was purified by chromatography on silica gel (7 g, 230-400 mesh), eluting with dichloromethane (15×10 mL); dichloromethanemethanol (15:1; 16×10 mL) to give 0.0476 g of pure 4-oxo-4-(4′-trifluoromethyl-biphenyl-4-yl)-butyric acid as an off-white solid; mp 172-174° C.