反应详情

Combine 3-(2-chloro-pyridin-3-yl)-5-methyl-isoxazole-4-carboxylic acid methyl ester (1.90 g, 0.0075 mol) with aqueous sodium hydroxide (2N, 15.0 mL, 0.03 mol), ethanol (3 mL), and tetrahydrofuran (3 mL). Stir for 4 hours at ambient temperature. Remove the organic solvents in vacuo and adjust the aqueous mixture to approx. pH 3.0 with aqueous hydrochloric acid. Extract with ethyl acetate and dry the combined extracts over sodium sulfate and concentrate in vacuo. Eluted over silica gel with methanol/dichloromethane allowing for isolation of the desired isoxazole acid as an off white solid (0.98 g, 55%). MS(ES): (M+1)+ 238.97, 240.97 m/z.

1. customRemove the organic solvents in vacuo
2. extractionExtract with ethyl acetate
3. dry with materialdry the combined extracts over sodium sulfate
4. concentrationconcentrate in vacuo
5. washEluted over silica gel with methanol/dichloromethane allowing for isolation of the desired isoxazole acid as an off white solid (0.98 g, 55%)