Methyl iodide → 5-(Methoxycarbonyl)thiophene-2-carboxylic acid

Reaction equation

[S:1]1[C:5]([C:6]([OH:8])=[O:7])=[CH:4][CH:3]=[C:2]1[C:9]([OH:11])=[O:10].[C:12](=O)([O-])[O-].[Na+].[Na+].CI>CN(C=O)C>[CH3:12][O:7][C:6]([C:5]1[S:1][C:2]([C:9]([OH:11])=[O:10])=[CH:3][CH:4]=1)=[O:8]

Participants

Procedure

1.72 g (10 mmol) of thiophene-2,5-dicarboxylic acid and 3.18 g (30 mmol) of sodium carbonate suspended in 25 mL of DMF were stirred with 623 μL of methyl iodide at room temperature overnight. The sodium salt of the desired product was extracted with water, and 12M of hydrochloric acid was added to the combined aqueous layer. The desired product was extracted with ethyl acetate, and the combined organic layer was washed with saturated aqueous ammonium chloride and dried over anhydrous magnesium sulfate. The desired product was purified by silica gel column chromatography to give 0.49 g of a colorless solid (yield 28%).