Nitromethane → 7-[(E)-2-nitroethenyl]-2,3-dihydro-1H-imidazo[1,2-b]pyrazole-1-carbaldehyde
Reaktionsgleichung
[N:1]1([CH:11]=[O:12])[C:8]2[N:4]([N:5]=[CH:6][C:7]=2[CH:9]=O)[CH2:3][CH2:2]1.C([O-])(=O)C.[NH4+].[N+:18]([CH3:21])([O-:20])=[O:19]>>[N+:18](/[CH:21]=[CH:9]/[C:7]1[CH:6]=[N:5][N:4]2[CH2:3][CH2:2][N:1]([CH:11]=[O:12])[C:8]=12)([O-:20])=[O:19]Komponenten
4
Versuchsvorschrift
A solution of 2,3-dihydro-1H-imidazo[1,2-b]pyrazole-1,7-dicarbaldehyde (1 g) and ammonium acetate (653 mg) in nitromethane (20 ml) was refluxed for 4 hours. The reaction mixture was evaporated under reduced pressure and extracted with dichloromethane. The extract was dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo to give 7-[(E)-2-nitroethenyl]-2,3-dihydro-1H-imidazo[1,2-b]pyrazole-1-carbaldehyde (1.00 g).