Pyridine → 3,5-dimethyl-1-pyridin-2-yl-1H-pyrazole-4-carboxylic acid ethyl ester
Reaction equation
[N:1]1[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[NH:7][NH2:8].[CH2:9]([O:11][C:12](=[O:20])[CH:13]([C:17](=O)[CH3:18])[C:14](=O)[CH3:15])[CH3:10].N1C=CC=CC=1>C(O)C>[CH2:9]([O:11][C:12]([C:13]1[C:14]([CH3:15])=[N:8][N:7]([C:2]2[CH:3]=[CH:4][CH:5]=[CH:6][N:1]=2)[C:17]=1[CH3:18])=[O:20])[CH3:10]Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
Similar to Example 1, 2-pyridylhydrazine (7.5 mmol, 0.8 g) and 2-acetyl-3-oxo-butyric acid ethyl ester (7.5 mmol, 1.3 g) were mixed in a solution of 50% pyridine in ethanol, then heated under reflux. The solvents were removed under vacuum and the residue purified over silica. The named product crystallized upon standing (m.p. 49° C.–50° C.).