反应 #2467968

反应方程式

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

potassium carbonate

Dimethyl sulfate

→

solid

收率 45.0%

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

收率 45.0%

溶剂

acetone

反应条件

后处理

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

实验过程

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).

来源