반응 #2467965

반응 방정식

ammonium hydroxide

Methyl 3-[(dimethylamino)diazenyl]thiophene-2-carboxylate

sulfuric acid

nitric acid

→

solid

수율 26.0%

Methyl 3-[(dimethylamino)diazenyl]-5-nitrothiophene-2-carboxylate

수율 26.0%

용매

water

반응 조건

후처리

1. 1
   workup.ADDITIONThe mixture was poured into ice
2. 2
   추출The solution was extracted with chloroform (3×100 mL)
3. 3
   세척the combined organic layer was washed with water, brine
4. 4
   건조dried over sodium sulfate
5. 5
   여과The solution was filtered
6. 6
   기타evaporated the solvent
7. 7
   기타The residue was chromatographed over silica gel column

실험 절차

Methyl 3-[(dimethylamino)diazenyl]thiophene-2-carboxylate (2 g, 9.38 mmol) was added slowly for 15 min at 0 to −5° C. to concentrated sulfuric acid (20 mL). Then concentrated nitric acid (0.54 mL, 70%, 10.7 mmol) was added to the above reaction mixture for 10 min and stirred at the same temperature for 1 h and rt for 16 h. The mixture was poured into ice cooled water and basified with ammonium hydroxide. The solution was extracted with chloroform (3×100 mL) and the combined organic layer was washed with water, brine and dried over sodium sulfate. The solution was filtered and evaporated the solvent. The residue was chromatographed over silica gel column using hexane-ethyl acetate (80:20) as eluents to give the product as a yellow color solid (450 mg, 26%), mp 128-130° C.

출처