Cycloisomerization of Oxindole-Derived1,5-Enynes: ACalcium (II)-Catalyzed One-Pot, Solvent-free Synthesis of Phenanthridinones, 3-(Cyclopentenylidene)indolin-2-ones and 3-Spirocyclic Indolin-2-ones

摘要

Calcium-catalyzed regioselective synthesis of oxindole-derived 1,5-enynes, followed by cycloisomerization, from readily accessible 3hydroxy- 3-(alkynyl) indolin-2-ones and styrenes in one-pot, under solvent-free conditions is described. This method offers the synthesis of diverse molecules: phenanthridinones, 3-(cyclopentenylidene) indolin- 2-ones, and 3-spirocyclic indolin-2-ones are obtained through cascade reactions including crossdehydrative- coupling, [3,3]-sigmatropic rearrangement, carbocyclization, isomerization, oxidativering rearrangement, and Diels-Alder cycloaddition. In addition, this method features atom-and stepeconomy, broad substrate scope, and high yields.