abstract |
The invention relates to a method for producing n-substituted 3-hydroxypyrazoles of formula (I), wherein R1 stands for optionally substituted alkyl, alkenyl, alkinyl, cycloalkyl, aryl or heteroaryl and R2 and R3 mean hydrogen, cyano, halogen and optionally substituted alkyl, alkenyl, alkinyl, cycloalkyl, aryl or heteroaryl, by oxidizing a corresponding pyrazolidin-3-ons. |