Competing transformations of 2-cyanoacetanilides in the reactions with derivatives of ethoxymethylenemalonic acid

Ethoxymethylenemalonodinitrile 1B and ethyl ethoxymethylenecyanoacetate 1C in cyclocondensations with 2-cyanoacetanilides 2 behave as a three-carbon fragment transfer reagent to afford the corresponding 5-cyano- and 5-ethoxycarbonyl-6-amino-1-aryl-3cyanopyridin-2(1H)-one derivatives 7B and 8C. One carbon transfer described earlier for such reactions with a use of diethyl 2-(ethoxymethylene)malonate 1A was observed only as a side process in the case of 1C leading to 2-amino-5-cyano-6-oxo-N,1-diaryl-1,6-dihydropyridine-3carboxamides.