L,3-Diazolium-4-olates

The mesoionic 1,2,3-triazolium-4-olates 361a,b and l,2,3-triazolium-4-thiolate 361c did not react with benzocyclopropene (113), and the attempted reaction between l,3-diazolium-4-olate 362 and benzocyclobutadiene failed (114). In contrast to these negative results, Ichinari et al. (249) found that the isomeric l,3-diazolium-4-olates (l,3-imidazolium-4-olates) 363 and 364 react with DMAD to form pyridones and pyrroles, respectively. 

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