Pyrido- and azepino-fused cycl[3.2.2]azines were obtained by the reaction of the corresponding pyrido- and azepino[hi]indolizines with electron-deficient acetylenes in the presence of appropriate oxidants. The reaction pathway of their preparation was proposed to be a sequence of Michael addition of indolizine to acetylene, 10π-electrocyclic reaction of Michael adduct, and dehydrogenation by means