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.
azaisobenzofuran - quinoxaline - quinazoline - phenazine - Diels-Alder reaction -
carbene
complexes
