Palladium-Catalyzed [2 + 2 + 1] Annulation of Alkyne-Tethered Aryl Iodides with Diaziridinone: Synthesis of 3,4-Fused Tricyclic Indoles
Lei Zhang, Junyu Chen, Tianshuo Zhong, Xiangyun Zheng, Jian Zhou, Xinpeng Jiang, Chuanming Yu
Abstract
A novel palladium-catalyzed [2 + 2 + 1] annulation of alkyne-tethered aryl iodides with diaziridinone was developed, leading to the formation of 3,4-fused tricyclic indoles. From a mechanistic standpoint, the formation of fused tricyclic indole scaffolds involved C,C-palladacycles, which were synthesized through the intramolecular reaction of aryl halides and alkynes. The cascade reaction described herein could be carried out with a broad range of substrates and provided various 3,4-fused tricyclic indoles with yields up to 98%.
Topics & Concepts
ChemistryTricyclicAnnulationAlkyneArylIntramolecular forcePalladiumIndole testCatalysisCombinatorial chemistryStereochemistryOrganic chemistryAlkylCatalytic C–H Functionalization MethodsSynthesis and Catalytic ReactionsCatalytic Cross-Coupling Reactions