Hydrochloric Acid → 2,5-Dihydroxyterephthalic acid

Participants

Reaction Conditions

Reaction Steps

Under nitrogen, 2.00 g (8.51 mmol) of 2,5-dichloroterephthalic acid was combined with 10 g of H2O. 0.938 g (8.85 mmol) of Na2CO3 was then added. The mixture was heated to reflux with stirring for 30 min, remaining under a nitrogen atmosphere. Another 1.31 g (12.34 mmol) of Na2CO3 was added to the reaction mixture and reflux was continued for 30 min. Separately, 12 mg of CuBr and 24 mg of rac-trans-N,N′-dimethylcyclohexane-1,2-diamine (Ligand F) were combined with 2 mL H2O under nitrogen. The resulting mixture was stirred under an air atmosphere until the CuBr was dissolved to give a deep purple solution. This solution was added to the stirred reaction mixture via syringe at 80° C. under nitrogen and stirred for 20 h at 80° C. After cooling to 25° C., the reaction mixture was acidified with HCl (conc.), producing a dark yellow precipitate. The yellow precipitate was filtered and washed with water. After drying, a total of 1.59 g (8.03 mmol, 94% yield) 2,5-dihydroxyterephthalic acid was collected. The purity was determined by 1H NMR to be 95%.

Provenance & Evidence