Sulfuric Acid → Methyl 5-Methoxy-2-thiophenecarboxylate

Participants

Reaction Conditions

Reaction Steps

To a 200 mL round-bottomed flask fitted with a condenser was added 5-(methyloxy)-2-thiophenecarboxylic acid (1.3 g, 8.22 mmol) in Methanol (40 mL). H2SO4 (5 mL, 94 mmol) was added slowly at room temperature and the reaction stirred at 50° C. overnight. The mixture was cooled to 0° C. and sat. NaHCO3 was added to neutral pH followed by 5N NaOH to pH 10. The mixture was partitioned between H2O/CHCl3 and the organic phase was separated and dried over Na2SO4. The solution was adsorbed onto silica and purified via column chromatography (5-50% EtOAc/Hexanes) affording the title compound (827 mg, 4.56 mmol, 56%): LC-MS (ES) m/z=173 (M+H)+.

Provenance & Evidence