Реакция #2467968

Уравнение реакции

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

potassium carbonate

Dimethyl sulfate

→

solid

Выход 45.0%

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

Выход 45.0%

Растворители

acetone

Условия реакции

Обработка

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

Методика

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).

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