1,2,3-Triazolium-1-unsubstituted methanides, carbon analogues of triazole-N-oxides: a 1,3-dipole cascade from 1,2,3-triazolium-1-methanide to 1,2,4-triazinium-4-methanide: new routes to pyrrolo [1,2-c] [1,2,3] triazoles, pyrrolo[1,2-d][1,2,4]triazines and substituted 1-aminopyrroles. Azolium 1,3-dipoles