Cycloaddition reactions of cyclopropenone with 1,2,4-triazines, a new synthesis of pyrazolo[1,2-a]1,2,4-triazin-6-ones

Article abstract of DOI:10.1002/ardp.19943270803

Contrary to cycloaddition reactions of cyclopropene, 3,3-dimethoxycyclopropene, and 1,2-diphenylcyclopropenone the unsubstituted cyclopropenone reacts regioselectively with the N=N-bond of various 1,2,4-triazines to yield novel pyrazolo[1,2-a]1,2,4-triazi