The calculated results show that the aza Wittig reaction is a two step reaction, having one four membered ring intermediate on its reaction surface.

All transition states, activation energies and potential curves of four possible reaction paths were obtained. It was found that the homolysis of n-no2 bond in five-membered ring is the initial step.

The compound 6-(2-methoxy phenoxy)-1, 4-dihydrogen-4-oxo-3-ethyl quinoline carboxylate is prepared with o-methoxyphenol and p-chloronitrobenzene as materials and through four-step reaction.