Acetone → 5-(4-methoxyphenyl)thiophene-2-carboxylic Acid

Participants

Reaction Steps

To a solution of 6.3 mL of n-butyllithium (2.5 M solution in hexane) in 50 mL of dry ether is added a solution of 3.0 g (15.8 mmol) of 2-(4-methoxyphenyl)thiophene in 20 mL of dry ether under N2 atmosphere. The mixture is stirred at room temperature for 3 hours and then heated at reflux for 30 minutes. After the reaction mixture is cooled to -78° C. with dry ice and acetone bath, dry CO2 gas is bubbled through the reaction mixture for 3 hours and the resulting solution is stirred at room temperature overnight. The reaction mixture is diluted with 200 mL of chloroform, washed with 1% HCl solution (200 mL) and with water (2×200 mL). The separated organic layer is dried over anhydrous Na2SO4 and concentrated under reduced pressure to give 1.8 g (50%) of 5-(4-methoxyphenyl)-2-thienoic acid.

Provenance & Evidence