반응 #2467968

반응 방정식

methyl 4-hydroxy-5-(methoxycarbonyl)-3-nitrothiophene-2-carboxylate

potassium carbonate

Dimethyl sulfate

→

solid

수율 45.0%

Methyl 4-methoxy-5-(methoxycarbonyl)-3-nitrothiophene-2-carboxylate

수율 45.0%

용매

acetone

반응 조건

후처리

1. 1
   workup.ADDITIONwas added to the above reaction mixture slowly
2. 2
   workup.ADDITIONa catalytic amount of KI was added
3. 3
   온도The mixture was refluxed for 4 h
4. 4
   기타the cooled reaction mixture
5. 5
   여과was filtered
6. 6
   세척the solids were washed with acetone
7. 7
   기타Acetone was removed under reduced pressure
8. 8
   기타the residue was chromatographed over silica gel column

실험 절차

To a solution of methyl 4-hydroxy-5-(methoxycarbonyl)-3-nitrothiophene-2-carboxylate (650 mg, 2.5 mmol) in acetone (20 mL) was added potassium carbonate (0.68 g, 5 mmol) at it Dimethyl sulfate (0.36 mL, 3.73 mmol) was added to the above reaction mixture slowly with stirring and a catalytic amount of KI was added. The mixture was refluxed for 4 h and the cooled reaction mixture was filtered and the solids were washed with acetone. Acetone was removed under reduced pressure and the residue was chromatographed over silica gel column using hexane-ethyl acetate (90:10) as eluents to give the product as a pale yellow color solid (0.3 g, 45%), mp 80-82° C. 1H NMR (400 MHz, CDCl3): δ 4.08 (3H, s), 3.94 (3H, s), 3.92 (3H, s).

출처