Bromine → 4-bromo-3-cyclopropyl-1-methyl-1H-pyrazole-5-carboxylic acid
Reaktionsgleichung
[CH:1]1([C:4]2[CH:8]=[C:7]([C:9]([OH:11])=[O:10])[N:6]([CH3:12])[N:5]=2)[CH2:3][CH2:2]1.[Br:13]Br>C(O)(=O)C>[Br:13][C:8]1[C:4]([CH:1]2[CH2:2][CH2:3]2)=[N:5][N:6]([CH3:12])[C:7]=1[C:9]([OH:11])=[O:10]Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
A solution, cooled to 0° C., of 100 mg (0.60 mmol) of 3-cyclopropyl-1-methyl-1H-pyrazole-5-carboxylic acid in 5 ml of acetic acid is admixed with 173 mg (1.08 mmol) of bromine and afterstirred overnight at room temperature. Acetic acid and bromine are drawn off on a rotary evaporator and the solid residue is washed with cyclohexane and a small amount of diethyl ether. This gives 69.0 mg of 4-bromo-3-cyclopropyl-1-methyl-1H-pyrazole-5-carboxylic acid (47%) as a yellowish solid.