반응 #8153

반응 방정식

p-Bromophenylhydrazine hydrochloride

2-acetyl-3-oxo-butyric acid ethyl ester

chloroform

→

1-(4-bromophenyl)-3,5-dimethyl-1H-pyrazole-4-carboxylic acid ethyl ester

용매

ethanol

pyridine

반응 조건

후처리

1. 1
   기타The solvents were removed under vacuum
2. 2
   workup.DISSOLUTIONThe residue was dissolved in 150 mL ether
3. 3
   세척washed with 50 mL water
4. 4
   기타to remove the pyridine
5. 5
   건조The ether was dried over sodium sulfate (NaSO4)
6. 6
   여과the solids filtered
7. 7
   기타the solvents were removed under vacuum
8. 8
   기타The resulting oil was purified on a silica column
9. 9
   기타The named product crystallized
10. 10
    기타synthesis the named product

실험 절차

p-Bromophenylhydrazine hydrochloride (10 mmol, 2.5 g) was added to 2-acetyl-3-oxo-butyric acid ethyl ester (10 mmol, 1.7 g) in ethanol (10 mL) and pyridine (10 mL). The mixture was stirred overnight at room temperature. Thin layer chromatographic (TLC) analysis using chloroform indicated the reaction was complete. The solvents were removed under vacuum. The residue was dissolved in 150 mL ether, then washed with 50 mL water to remove the pyridine. The ether was dried over sodium sulfate (NaSO4), the solids filtered, then the solvents were removed under vacuum. The resulting oil was purified on a silica column. The named product crystallized upon standing in the column effluent, m.p. 71° C.–73° C. Analysis by 1H-NMR and 13C-NMR verified synthesis the named product.

출처