تفاعل #8153

معادلة التفاعل

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

المذيبات

ethanol

pyridine

ظروف التفاعل

المعالجة

1. 1
   أخرىThe solvents were removed under vacuum
2. 2
   workup.DISSOLUTIONThe residue was dissolved in 150 mL ether
3. 3
   غسيلwashed with 50 mL water
4. 4
   أخرىto remove the pyridine
5. 5
   تجفيفThe ether was dried over sodium sulfate (NaSO4)
6. 6
   ترشيحthe solids filtered
7. 7
   أخرىthe solvents were removed under vacuum
8. 8
   أخرىThe resulting oil was purified on a silica column
9. 9
   أخرىThe named product crystallized
10. 10
    أخرىsynthesis the named product

الإجراء التجريبي

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.

المصدر