Ethylidene diacetate (EDA) reacts with formamide or acetamide under stoichiometric base or catalytic Lewis acid conditions to afford the corresponding ethylidene bisamides and N- vinylamides. Sn (OAc) 2 afforded an overall 82.6% selectivity to the desired acetamide derivatives. Sn (OAc) 2 and Zn (OAc) 2 facilitate amide attack at the tertiary carbon of EDA.