Methanesulfonic Acid → Ethyl 3-difluoromethyl-1-methyl-4-pyrazole carboxylate
Reaktionsgleichung
[F:1][CH:2]([F:14])[C:3]1[N:7](C)[N:6]=[CH:5][C:4]=1[C:9]([O:11][CH2:12][CH3:13])=[O:10].P([O-])(OC)O[CH3:17].CS(O)(=O)=O>>[F:1][CH:2]([F:14])[C:3]1[C:4]([C:9]([O:11][CH2:12][CH3:13])=[O:10])=[CH:5][N:6]([CH3:17])[N:7]=1Komponenten
4
Reaktionsbedingungen
- Temperatur
- 170 °C
Versuchsvorschrift
To 20.4 g of ethyl 5-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylate (iso-DFPE) was added 11.3 g of dimethyl phosphite and 0.82 g of methane sulfonic acid. The mixture was heated to 170° C. and stirred for 7 hours. The solution was cooled and distilled to recover recycled trimethyl phosphate and 0.9 g of starting ethyl 5-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylate (iso-DFPE). The remaining solution was added to 50 g of cold water. The solution was allowed to stir for 30 min. The precipitating solid was filtered and dried to give 14.1 g of product.