반응 #2467972

반응 방정식

K2CO3

dimethylamine

methyl 3-amino-5-phenylthiophene-2-carboxylate

HCl

NaNO2

→

solid

수율 76.0%

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

수율 76.0%

용매

H2O

H2O

acetone

반응 조건

후처리

1. 1
   workup.DISSOLUTIONto dissolve the product
2. 2
   workup.STIRRINGThe mixture was stirred at 0-5° C. for 1 h
3. 3
   workup.ADDITIONpoured into ice cold water
4. 4
   추출The solution was extracted with chloroform (3×100 mL)
5. 5
   세척The combined CHCl3 layer was washed with water, brine
6. 6
   건조dried over sodium sulfate
7. 7
   여과The solution was filtered
8. 8
   기타evaporated the solvent
9. 9
   기타The residue was chromatographed over silica gel column

실험 절차

To a solution of methyl 3-amino-5-phenylthiophene-2-carboxylate (5 g, 21.4 mmol) and conc. HCl (9 mL, 85.8 mmol) in H2O (51 mL) was added acetone (30 mL) to dissolve the product. Then NaNO2 (1.7 g, 23.6 mmol) was added in portions for 15 min at 0° C. After stirring at 0-5° C. for 1 h, the reaction mixture was added to the solution of K2CO3 (11.2 g, 81.5 mmol) and dimethylamine (8.5 mL, 40%, 77.2 mmol) in H2O (60 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 (90:10) as eluents to give the product as a pale brown color solid (3.8 g, 76%), mp 92-94° C. 1H NMR (400 MHz, DMSO-d6): δ 7.78-7.80 (2H, m), 7.64 (1H, s), 7.46-7.52 (3H, m), 3.84 (3H, s), 3.60 (3H, s), 3.28 (3H, s); LC-MS (positive ion mode): m/z 290 (M+H)+.

출처