反应详情

DL-4,5-Dihydro-1-[3-(acetylthio)-1-oxopropyl]-3-phenyl-1H-pyrazole-5-carboxylic acid (6.0g) is treated in an argon atmosphere with 40ml of a cold solution of 6.5N ammonium hydroxide. After 30 minutes at room temperature, the solution is washed with ethyl acetate, treated with concentrated hydrochloric acid to pH 2.5 and extracted with ethyl acetate. The extract is dried over magnesium sulfate and concentrated in vacuo to an oil. Trituration of the oil with ether yields 3.6g of the title compound, melting point 118°-120° C.

1. washthe solution is washed with ethyl acetate
2. additiontreated with concentrated hydrochloric acid to pH 2.5
3. extractionextracted with ethyl acetate
4. dry with materialThe extract is dried over magnesium sulfate
5. concentrationconcentrated in vacuo to an oil