Ring Transformation of Cinnolines with Ynamines

Cinnolines having electron-withdrawing substituents at 4-position reacted with ynamines to give naphthalene derivatives andlor quinoline derivatives through [4+2] cycloaddition followed by elimination of nitrogen or hydrogen cyanide.It is known that electron-deficient heternaromatic systems easily undergo inverse-electron demanded Diels-Alder reactions: ' so that these properties were widely applied to synthesis of natural products."