Hydrazine hydrate (1:1) → Ethyl 5-(4-benzyloxyphenyl)-2H-pyrazole-3-carboxylate
Reaction equation
[CH2:1]([O:8][C:9]1[CH:14]=[CH:13][C:12]([CH:15](C=O)[C:16](=O)[C:17](OCC)=O)=[CH:11][CH:10]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[OH2:25].[NH2:26][NH2:27]>C(O)C>[CH2:1]([O:8][C:9]1[CH:10]=[CH:11][C:12]([C:15]2[CH:16]=[C:17]([C:9]([O:8][CH2:1][CH3:2])=[O:25])[NH:26][N:27]=2)=[CH:13][CH:14]=1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
A suspension of ethyl 4-benzyloxyphenyl-2,4-dioxobutanoate (35.86 g) in ethanol (300 mL) is treated with hydrazine hydrate (6 mL) and the mixture is heated at reflux for 2 hours. The reaction mixture is cooled to room temperature, filtered, and the solid washed with ethanol to give ethyl 5-(4-benzyloxyphenyl)-2H-pyrazole-3-carboxylate (25 g), m.p. 160-170° C.