Efficient synthesis of functionalized spiro[indoline-3,4′-pyridines] and spiro[indene-2,4′-pyridines] via a three-component reaction

Abstract

The three-component reactions of α,β-unsaturated N-arylaldimines, dimethyl acetylenedicarboxylate (methyl propiolate) and isatylidene malononitriles in dry acetonitrile at room temperature afforded polysubstituted spiro[indoline-3,4′-pyridines] in good yields and with high diastereoselectivity. Under similar reaction conditions, the corresponding functionalized spiro[indene-2,4′-pyridines] were also obtained from the three-component reactions containing 2-(1,3-dioxo-1H-inden-2(3H)-ylidene)malononitrile.