| 摘要 |
PURPOSE:To easily produce the subject compound useful as a raw material for pharmaceuticals and agricultural chemicals in high yield, with a simple operation and apparatus without using heavy metal oxidizing agent having strong toxicity by oxidizing pyrazolealdehydes with oxygen in the presence of a catalyst. CONSTITUTION:The objective compound of formula II can be produced on an industrial scale at a low cost, without using a heavy metal oxidizing agent which necessitates troublesome operation because of the generation of a large amount of waste heavy metal, by oxidizing a compound of formula I [R<1>-R<3> are H, alkyl, haloalkyl, alkoxyalkyl, substituted or unsubstituted (aryl or aralkyl) or R<1> is alkenyl, haloalkenyl, substituted or unsubstituted heteroaryl and R<2>-R<3> are halogen, NO2, alkoxy, substituted or unsubstituted aryloxy] with oxygen [including oxygen diluted with an inert gas such as nitrogen (e.g., air) in addition to pure oxygen) in the presence of a catalyst (preferably platinum or palladium). |
