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Updated: Jun 16, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Sequential Organic/Metal Relay Catalysis Enabling the Regioselective Synthesis of Functionalized α-Carbolines from
Qing He1, Xiaoyu Li1, Xing Ye1
1State Key Laboratory of Discovery and Utilization of Functional Components in Traditional Chinese Medicine, Guizhou Provincial Key Laboratory of Innovation and Manufacturing for Pharmaceuticals, Guizhou Medical University, Guiyang 561113, China.
Abstract:
Herein, we report an efficient organo/silver relay catalytic system that enables the sequential Mannich/6-endo-dig cyclization/aromatization cascade of β,γ-alkynyl-α-ketimino esters with indolin-2-imines, which exhibits remarkable substrate generality and affords a broad range of α-carboline derivatives in good to excellent yields. Mechanistic studies confirm a stepwise relay catalytic pathway, and the practical utility of this protocol is verified by late-stage functionalization, gram-scale synthesis, and facile synthetic transformations of the resulting α-carboline products for accessing more elaborate N-heterocyclic derivatives.
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