Micellar Effects upon the Hydrolysis of Activated Amides. Mechanistic Aspects

Article abstract of DOI:10.1021/j150643a041

Reactions of OH^- in water with N-acylpyrrole, -indole, and -carbazole (acyl = acetyl or benzoyl) are second order in OH^- in 10^-3 M NaOH and first order in more concentrated OH^-, but reaction in micelles of cetyltrimethylammonium bromide (CTABr) is first order in micellar-bound OH^- for both 10^-3 and 0.05 M NaOH.Reactions are inhibited by anionic micelles of sodium lauryl sulfate (NaLS).The rate-surfactant profiles for rate enhancements in CTABr, and inhibition in NaLS, are analyzed in terms of the distribution of OH^- and amide between aqueous and micellar pseudophases: second-order rate constants for attack of OH^- upon amide are lower in the micellar pseudophase than in water.Micellar effects upon reaction of OH^- with anilides have been analyzed, giving second-order rate constants in the micellar pseudophase which are very similar to those in water.