Hydrazine hydrate (1:1) → 3-(2,4-Dihydroxyphenyl)-4-(4-methoxyphenyl)-5-methyl-1H-pyrazole
Reaktionsgleichung
O.[NH2:2][NH2:3].[OH:4][C:5]1[CH:14]=[C:13]2[C:8]([C:9](=O)[C:10]([C:16]3[CH:21]=[CH:20][C:19]([O:22][CH3:23])=[CH:18][CH:17]=3)=[C:11]([CH3:15])[O:12]2)=[CH:7][CH:6]=1>C(O)C>[CH3:23][O:22][C:19]1[CH:20]=[CH:21][C:16]([C:10]2[C:9]([C:8]3[CH:7]=[CH:6][C:5]([OH:4])=[CH:14][C:13]=3[OH:12])=[N:2][NH:3][C:11]=2[CH3:15])=[CH:17][CH:18]=1Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
Hydrazine hydrate (2 ml, ˜55%) was added to a suspension of 7-hydroxy-3-(4-methoxy-phenyl)-2-methyl-chromen-4-one (0.57 g, 2 mmol) in ethanol (15 ml) and the mixture heated under reflux for ˜5 hrs., to give a pale brown solution. The solution was allowed to cool and concentrated to a pale yellow solid, the solids were washed with water, to give the pyrazole as an off-white solid, dried in vacuo, (0.45 g). Sample was recrystallised from boiling toluene, to give the 4-[4-(4-methoxy-phenyl)-5-methyl-1H-pyrazol-3-yl]-benzene-1,3-diol as a pale brown crystalline solid, washed with hexane, dried in vacuo.