Differentiation of Nucleophilic and General Base Catalysis in the Hydrolysis of N-Acetylbenzotriazole Using the Proton Inventory Technique

Article abstract of DOI:10.1021/jo00337a027

The hydrolysis of N-acetylbenzotriazole is catalyzed by acetate and imidazole by two different modes as shown by the proton inventory technique.Acetate acts as a general base catalyst to abstract a proton from the attacking water molecule.The unexpected upward curvature in the proton inventory plot can be attributed to a reactant-state isotopic fractionation factor contribution from acetate ion.The proton inventory for imidazole catalysis exhibits downward curvature and is shown to be consistent with a nucleophilic catalyses role for imidazole.The intermediate, 1-acetylimidazole, then undergoes rate-determining water-catalyzed hydrolysis via the expected mechanism.