Synthesis
1H-Benzotriazole-5-carboxylic acid was formed of carboxytriazole (3.91 g, 24 mmol), 4-dimethylaminopyridine (0.32 g, 2.6 mmol), dimethylformamide (58 g) andatert-butyl methyl ether (46 g) solution of ZTETRAOL 2000s produced by the SOLVAY SOLEXIS company (Mn of 1730 for Rf(F)=-CF2O (CF2CF2O)m(CF2O)nCF2-) (13.26 g, 6.0 mmol) which had four terminal hydroxyl groups, as a perfluoropolyether were added sequentially to a three-necked flask which had been fitted with a nitrogen bubbling tube and a stirrer. 1-Ethy3- (3-dimethylaminopropyl)carboxylmide hydrochloride (4.60 g, 24 mmol) was added at room temperature and stirred for 24 hours at 50°C. Water (60 g) and methyl isobutyl ketone (60 g) were added to the reaction solution and the liquid was partitioned. The organic layer was washed two or three times with 1% hydrochloric acid aqueous solution (50 g) and saturated salt water (50 g) and then dried with anhydrous sodium sulphate and concentrated and 1H-Benzotriazole-5-carboxylic acid was obtained. Yield (10.1 g).
