Dimethylformamide → 5-(3,3-Dimethyl-but-1-ynyl)-3-iodo-thiophene-2-carboxylic acid methyl ester

Participants

Reaction Steps

To a solution of 5-(3,3-dimethyl-but-1-ynyl)-3-iodo-thiophene-2-carboxylic acid (1.0 g, 3.0 mmol) and DMF (20 μL) in dry dichloromethane (10 mL) was added oxalyl chloride (508 μL, 6.0 mmol) at room temperature. After stirring at room temperature for 90 min, the reaction was concentrated in vacuo to remove volatiles. The residue was dissolved in pyridine (5 mL) and methanol (5 mL) and stirred for 2 h. The volatiles were removed in vacuo and the residue was participated between ether (150 mL) and saturated NH4Cl solution (50 mL). The organic layer was washed with saturated NH4Cl solution (50 mL) and dried over Na2SO4. After concentration in vacuo, the residue was purified by silica gel chromatography (EtOAc/hexanes) to give the desired product (835 mg, 80%).

Provenance & Evidence