Microwave Irradiation as an Efficient Tool for the Generation of N-Heterocyclic o-Quinodimethanes: Synthesis of Polyheterocyclic Compounds by Diels-Alder Reactions - Díaz-Ortiz, Ángel; Herrero, María A; de la Hoz, Antonio; Moreno, Andrés; Carrillo, José R (Synlett, 2006)