By reaction of arylazides having no electron-withdrawing groups with the enolate ion of the acetaldehyde (formed by cycloreversion of THF in the presence of n-butyllithium), 1-aryl-4, 5- dihydro-5-hydroxy-1H-1, 2, 3-triazoles could be isolated and then characterized. Further reaction of such hydroxytriazolines with the same enolate ion afforded substantial amounts of the corresponding N-formylanilines, confirming their intermediacy in the previously ...
