Sodium Hydroxide → 7-Bromo-1-benzofuran-5-carboxylic acid
Reaction equation
C[O:2][C:3]([C:5]1[CH:6]=[C:7]([Br:14])[C:8]2[O:12][CH:11]=[CH:10][C:9]=2[CH:13]=1)=[O:4].[OH-].[Na+]>C(O)C>[C:3]([C:5]1[CH:6]=[C:7]([Br:14])[C:8]2[O:12][CH:11]=[CH:10][C:9]=2[CH:13]=1)([OH:4])=[O:2]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution of 0.52 gm (2.03 mMol) 5-methoxycarbonyl-7-bromobenzofuran and 0.41 gm (10.13 mMol) sodium hydroxide in 4 mL ethanol was stirred at room temperature until all of the starting material had been consumed. The reaction mixture was concentrated under reduced pressure and the residue dissolved in water. This solution was then made basic by the addition of 1N sodium hydroxide and was extracted well with ethyl acetate. The remaining aqueous phase was made acidic (pH about 2) by treatment with potassium hydrogen sulfate and the resulting solid removed by filtration. The aqueous phase was extracted well with ethyl acetate and the organics were combined and concentrated under reduced pressure to provide 0.40 gm (82%) of 5-carboxy-7-bromobenzofuran as an off-white solid.