Acetic Acid → 5-Bromothiophene-3-carboxylic acid

Participants

Reaction Steps

Prepare a solution of thiophene carboxylic acid (500 mg, 3.90 mmol) in HOAc (5 mL). Add Br2 (0.17 mL, 0.85 mmol), in HOAc (3 mL), dropwise. Then stir the mixture for 15 minutes at room temperature under nitrogen. Quench the reaction with ice cold water and stir for an additional 10 minutes. Cool the solution −10° C. when the product will precipitate out. Filter the solution, rinse the filter cake with ice cold water, and dry the product to afford 473 mg of 5-bromothiophene-3-carboxylic acid as a white solid. 1H NMR (dimethylsulfoxide-d6) δ 12.90 (br s, 1H), 8.18 (d, J=1.5 Hz, 1H), 7.46 (d, J=1.5 Hz, 1H).

Provenance & Evidence