PMGB

To a solution of the ester (0.004 mol) in 8 mL ethanol was added 4 mL 1N aq. NaOH solution. The resulting mixture was stirred at rt for overnight (12 h). The reaction mixture was concentrated and the residue (water solution) was cooled in an ice bath and acidified with 10 mL of 1N HCl solution until pH 6. The white precipitate (product) formed was filtered and washed with water and air dried to give the corresponding carboxylic acid (white solid, 93% yield) .