Kinetics and mechanism of large rate enhancement in an acidic aqueous cleavage of the tertiary amide bond of N-(2-methoxyphenyl)-N′-morpholinophthalamide (1)

The rate of conversion of 1 to N-(2-methoxyphenyl)phthalimide (2) within [HCl] range 5.0 × 10−3–1.0 M at 1.0 M ionic strength (by NaCl) reveals the presence of both uncatalyzed and specific acid-catalyzed kinetic terms in the rate law. Intramolecular carboxamide group-assisted cleavage of amide bond of 1 reveals rate enhancement of much larger than 106-fold compared to the expected rate of analogous intermolecular reaction.