1. D. Pocar, E. Roversi, P. Trimarco and G. Valgattarri, Liebig Ann. Chem., 487 (1995).
2. Triazolines 6a,b were obtained in a previous work and transformed into the corresponding amidines 7a,b, which were used as synthons for the preparation of heterocyclic compounds and readily underwent ring closure to afford aminoquinolines [5]. By-products were neither isolated nor characterized.
3. v-Triazolines. Part 37. Rearrangement reactions of 5-amino-1-(2-formyl-, -benzoyl-, -cyano-aryl)-ν-triazolines: new synthesis of 2-amino- and 2,4-diamino-quinolines and 2,4-diamino-1,7-naphthyridines
4. In the case of triazoline 6d a small amount of 3,5-diaryl-2-morpholinofuran was produced. This product is explained by an autocondensation reaction of the tolylacetadehyde to the corresponding 2,4-ditolyl-2-butenal, which by reacting with morpholine yielded the corresponding enamine (i.e. 4-(2,4-di-p-tolylbuta-1,3-dienyl)-morpholine). Spontaneous oxidation of the latter yielded the observed furan derivative. Autooxydation of dienes to furans has been reported [7a,b].