One-Pot Three-Component Synthesis of Quinoxaline, Quinazoline, and Phenazine Ring Systems Using Fischer Carbene Complexes.

One-pot, three-component synthesis of nitrogen-containing polycyclic heterocycles bearing two nitrogen atoms such as quinoxaline, quinazoline, and phenazine derivatives by the coupling of appropriate vicinal alkynylheteroaryl carbonyl derivatives with Fischer carbene complexes and dienophiles has been investigated. This involves the generation of furo[3,4-b]pyrazines, furo[3,4- d]pyrimidines, and furo[3,4-b]quinoxalines as transient intermediates, which were trapped with suitable Diels-Alder dienophiles in an inter- or intramolecular fashion. [ABSTRACT FROM AUTHOR]