Abstract 1-N-Alkyl-1-azapenta-1, 3-dienes 2 smoothly reacted with various mesoionic oxazolones 1 to afford 3, 4-di-hydro-2-pyridones 3 in excellent yields and there was no evidence for the formation of any products arising from the cycloaddition on the carbon [BOND] carbon double bond or on the azomethine function.
