Aza- and Diazaannulenones. Influence of Nitrogen Position on Their Reactivity and Stability

Article abstract of DOI:10.1021/jo00018a040

Three new elusive intermediates, 3-aza-2,4-cyclopentadienone, 2,5-diaza-2,4-cyclopentadienone, and 3,4-diaza-2,4-cyclopentadienone, are reported.The three species can act either as dienes or as dienophiles in Diels-Alder reactions.The influence of the number and position of nitrogen atoms on their stability is studied.