反应详情

To a solution of methyl 3-[3-(trifluoromethyl)phenyl]-4,5-dihydroisoxazole-5-carboxylate (2.3 g, 8.4 mmol) in THF (10 mL) was added 2 M of sodium hydroxide in water (10 mL) at 0° C. The reaction mixture was slowly warmed to ambient temperature, stirred for 2 h, neutralized with 2 N HCl to pH 7, and extracted with ethyl acetate (2×50 mL). The organic extracts were combined, washed with saline solution (50 mL), dried over sodium sulfate, concentrated in vacuo. The residue was chromatographed on silica gel, eluting with methylene chloride/methanol (95/5 to 80/20). The appropriate fractions were combined and concentrated in vacuo to give 3-[3-(trifluoromethyl)phenyl]-4,5-dihydroisoxazole-5-carboxylic acid (2.18 g, 100%) as a white crystalline solid. LCMS: 258.2 (M−H−, 100%).

1. extractionextracted with ethyl acetate (2×50 mL)
2. washwashed with saline solution (50 mL)
3. dry with materialdried over sodium sulfate
4. concentrationconcentrated in vacuo
5. customThe residue was chromatographed on silica gel
6. washeluting with methylene chloride/methanol (95/5 to 80/20)
7. concentrationconcentrated in vacuo