Hydrolysis of 4-Nitro-2-(trifluoroacetylamino)benzoic acid: Buffer catalysis, micellar catalysis and intramolecular general acid catalysis

Abstract

The hydrolysis of 4-nitro-2-(trifluoroacetylamino)benzoic acid was studied over the pH range 0-13. In strongly acidic solution (pH 0-3), intramolecular general acid catalysis was observed. In alkaline solution, rate determining protonation of the nitrogen atom of the intermediate complex formed by attack of hydroxide ion on the substrate, was observed. The alkaline hydrolysis was subject to significant micellar catalysis and this was accompanied by a change of mechanism to solvent assisted C-N bond breaking. At intermediate pH (4-8), the reaction was subject to significant buffer catalysis, and deprotonation of the intermediate formed by the attack of water on the substrate was proposed.