Functional micellar catalysis. Part 5. Catalysis of activated amide hydrolysis by hydroxy and imidazole functionalized surfactant systems

Abstract

The hydrolysis of N-(n-butyl)-2,4-dinitrotrifluoroacetanilide (IX), N-acetylimidazole (Xa), and N-hexanoylimidazole (Xb), in the pH range 7–8.5, is catalysed by micelles and co-micelles (with cetyltrimethylammonium bromide) of functional surfactants containing the hydroxy-group and/or the imidazole ring [(I)–(VIII)]. The kinetic effects here observed are significantly different from those previously reported for the same micellar reagents in the hydrolysis of p-nitrophenyl alkanoates. Such differences are ascribed to a change in the rate-limiting step of the acylation of the micellar functions, assuming a common nucleophilic mode of action of the functional micelles in the cleavage of activated esters and amides.