The reaction of unsymmetrically disubstituted hydrazines, epoxides, and carboxylic acid esters gives 1, ldi-substituted 1-(Zhydroxyalkyl-or aryl-) aminimides in excellent yields. Evidence is presented to support a primary reaction between the hydrazine and the epoxide to give an aminimine which subsequently reach with the ester to give the aminimide. The aminimide may be pyrolyzed to give an isocyanate and a@-hydroxy tertiary amine which ...