| 摘要 |
The present invention relates to a process for preparing N-substituted 2-pyrazolin-5-ones of the formula Iwhere R has the meaning given in claim 1, which comprises reacting a compound of the formula IIwhere R, X and Y have the meanings given in claim 1, at elevated temperature with a molar excess of alkali metal hydroxide in an aqueous reaction medium and then adjusting the pH to pH<=6 by adding an acid. |
