Hydrochloric Acid → Methyl 2-(5-formylthiophen-2-yl)acetate

Participants

Reaction Conditions

Reaction Steps

To a suspension of aluminium trichloride (853 mg, 6.4 mmol) in dichloromethane (4 mL) at −10° C. was added a solution of methyl 2-(2-thienyl)acetate (500 mg, 3.2 mmol) in dichloromethane (3 mL). The resulting solution was stirred at −10° C. for 10 minutes. A solution of dichloro(methoxy)methane (434 μL, 4.8 mmol) in dichloromethane (3 mL) was then added dropwise over 30 minutes. The reaction mixture was stirred at −10° C. for 1 h. The resulting solution was poured into a flask containing water (20 mL), crushed ice and concentrated HCl (1 mL) and stirred vigorously for 30 minutes. The solution was washed with dichloromethane (3×20 mL) and the combined organic phases washed with aqueous saturated sodium bicarbonate (30 mL) followed by brine (30 mL). The phases were separated over a hydrophobic frit and concentrated in vacuo to give the title compound as a red oil (533 mg, 91%) which was used in the next step without further purification.

Provenance & Evidence