Propionic anhydride → (E)-3-(2,3-dichloro-styryl)-5-ethyl-1,2,4-oxadiazole
Reaktionsgleichung
[Cl:1][C:2]1[C:13]([Cl:14])=[CH:12][CH:11]=[CH:10][C:3]=1/[CH:4]=[CH:5]/[C:6](=[N:8][OH:9])[NH2:7].[C:15](OC(=O)CC)(=O)[CH2:16][CH3:17]>>[Cl:1][C:2]1[C:13]([Cl:14])=[CH:12][CH:11]=[CH:10][C:3]=1/[CH:4]=[CH:5]/[C:6]1[N:7]=[C:15]([CH2:16][CH3:17])[O:9][N:8]=1Komponenten
3
Versuchsvorschrift
7.0 g (0.03 tool) of (E)-2,3-dichlorocinnamamide oxime are initially introduced into 7 ml of propionic anhydride and the mixture is then stirred at reflux temperature for 2 hours. Subsequently, the whole batch is concentrated in vacuo, and the residue is stirred with sodium carbonate solution and extracted with methylene chloride. The organic phase is dried over sodium sulphate and the solvent is distilled off. 4.7 g (58.2% of theory) of (E) -3- (2,3 -dichloro-styryl) -5-ethyl-1,2,4-oxadiazole are obtained.
Aufarbeitung
- temperatureat reflux temperature for 2 hours
- concentration