Phenylboronic Acid → 3-Phenyl-2-furoic acid

Participants

Reaction Steps

To 3-bromo-2-furancarboxylic acid (540 mg, 2.8 mmol dissolved in DME (105 ml)) was added of (Ph3P)4Pd (936 mg, 0.81 mmol), and the resulting solution was stirred at room temperature for 15 min. The mixture was treated with 500 mg (3.0 mmol) of benzene boronic acid, an aqueous solution of 2M NaHCO3 (4 mmol) and heated to reflux for 10 hours. After cooling to room temperature, the solvent was partially removed under reduced pressure, and the resulting mixture was extracted twice with diethyl ether. The water layer was acidified with 10% HCl and extracted with ethyl acetate (5 times). The combined organic layers were washed with brine, dried (Na2SO4), and evaporated under reduced pressure. The residue was crystallized from a mixture of n-hexane/ethyl acetate (about 8:2) to give the title compound. Yield: 70%.

Provenance & Evidence