Evidence for the participation of neighboring -CONH 2 group in the ammonolysis of disubstituted amide was obtained. The surprising conversion of I into 3 in very. mild conditions is a process formed by two consecutive first order reactions. Kinetics were performed in ethanol at various temperatures and Nil 3 concentrations. The ammonolysis of the isolated intermediate 2 allowed the unambiguous attribution of k I and k2 to steps I --~2 and 2-a,3, respectively ( Scheme 1 ). The thermodynamic parameters of activation for both steps of the process were evaluated.
Recently we reported an interesting case of intramolecular participation of amide group which induces the acid hydrolysis of methyl ether linkage in very mild conditions 1 . During enantioselective synthesis of the natural and unnatural a-aminoacids we observed a fitrther example of neighboring -CONH 2 group assistance. In fact, by subjecting lactone 12 to ammonolysis (5 hours at r.t. in NI-I 3 saturated ethanol) in order to obtain the diamide 2, to our great surprise we observed the formation of 3 (and (R)-lactamide) exclusively in practically quantitative yield (see Scheme 1).