반응 #2467981

반응 방정식

HCl

NaNO2

methyl 4-aminothiophene-2-carboxylate

K2CO3

dimethylamine

→

solid

수율 10.8%

Methyl 4-[(dimethylamino)diazenyl]thiophene-2-carboxylate

수율 10.8%

용매

H2O

H2O

반응 조건

후처리

1. 1
   workup.STIRRINGThe mixture was stirred at 0-5° C. for 1 h
2. 2
   workup.ADDITIONpoured into ice cold water
3. 3
   추출The solution was extracted with chloroform (3×100 mL)
4. 4
   세척The combined CHCl3 layer was washed with water, brine
5. 5
   건조dried over sodium sulfate
6. 6
   여과The solution was filtered
7. 7
   기타evaporated the solvent
8. 8
   기타The residue was chromatographed over silica gel column

실험 절차

To a solution of methyl 4-aminothiophene-2-carboxylate (1.7 g, 10.82 mmol) and cone. HCl (4.6 mL, 43.5 mmol) in H2O (20 mL) was added NaNO2 (0.84 g, 12.17 mmol) in portions for 5 min at 0° C. After stirring for 0.5 h at 0-5° C., the reaction mixture was added to the solution of K2CO3 (5.8 g, 42 mmol) and dimethylamine (4.6 mL, 40%, 40.9 mmol) in H2O (30 mL) at 0° C. The mixture was stirred at 0-5° C. for 1 h and poured into ice cold water. The solution was extracted with chloroform (3×100 mL). The combined CHCl3 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-EtOAc (80:20) as eluents to give the product as light red color solid (250 mg), which was recrystallized from chloroform-hexane (110 mg), mp 90-92° C. 1H NMR (400 MHz, CDCl3): δ 7.93 (1H, d, J=1.6 Hz), 7.31 (1H, d, J=1.6 Hz), 3.88 (3H, s), 3.31 (6H, br s).

출처