microwave-assisted synthesis of novel functionalized ketenimines and azadienes via a solvent-free reaction of isatoic anhydride, alkyl-isocyanides and dialkyl acetylenedicarboxylates

Ketenimines and azadienes are transient intermediates in organic chemistry especially in elimination-addition processes and in the formation of heterocyclic systems. these compounds play a considerable role as intermediates in the synthesis of heterocyclic ring systems. in this present research synthesis of novel ketenimines and azadienes via multicomponent reactions (mcrs) based on alkyl-isocyanides is reported. following our ongoing interest in isocyanide-based mcrs, we reported stereoselective reactions between 4h-3,1-benzoxazine-2,4(1h)-dione (isatoic anhydride) with dialkylacetylenedicarboxylates in the presence of alkyl isocyanides under solvent-free microwave conditions which leads to novel functionalized ketenimines and azadienes in a green route. the results show that the microwave-assisted leaching process has advantages over the conventional ones, concerning energy-consumption, processing time, and environmental protection.