Citation: Yu Liu, Lan Bao, Xiang Lyu, Zhonglin Wang, Zhengrun Chen, Jinhuan Dong, Xianxiu Xu, Zhongyan Hu. Divergent reactions of indolyl vinyl isonitriles: A facile access to skeletally diverse carboline-based biheteroaryls[J]. Chinese Chemical Letters, ;2026, 37(9): 112201. doi: 10.1016/j.cclet.2025.112201 shu

Divergent reactions of indolyl vinyl isonitriles: A facile access to skeletally diverse carboline-based biheteroaryls

Yu Liu ^a ,
Lan Bao ^b ,
Xiang Lyu ^c ,
Zhonglin Wang ^a ,
Zhengrun Chen ^a ,
Jinhuan Dong ^a ,
Xianxiu Xu ^{a, *,} ,
Zhongyan Hu ^{a, *,}

a.
College of Chemistry, Chemical Engineering and Materials Science, Shandong Key Laboratory of Next-Generation High-Performance OLED Display Material, Shandong Normal University, Ji'nan 250014, China
b.
College of Biological and Chemical Engineering, Qilu Institute of Technology, Ji'nan 250200, China
c.
School of Pharmaceutical Sciences & Institute of Materia Medica, Shandong First Medical University, Ji'nan 250117, China

xuxx677@sdnu.edu.cn

huzy@sdnu.edu.cn

Received Date: 28 September 2025
Revised Date: 18 November 2025
Accepted Date: 28 November 2025
Available Online: 29 November 2025

Figures(5)

Skeletal transformations of heteroaromatic compounds via endocyclic bond cleavage have emerged as powerful tools in modern organic synthesis. Nonetheless, selective cleavage of the C2−N1 bond in indoles without the assistance of metal reagents or additives remains highly challenging, owing to the strong aromatic stabilization and intrinsic bond strength of the indole framework. Herein, we present a distinctive dimerization of C3-substituted indolyl vinyl isonitriles that proceeds through a sequential "head-to-head" cross-coupling, pyridannulation, and C2−N1 bond cleavage cascade. This transformation not only disrupts the indole core but also forges a new pyridine ring, thereby providing a metal-free and efficient route to highly functionalized 1-(2-pyridyl)-β-carbolines. Notably, an oxidative aromatic dimerization of C3- and C2-substituted heteroaryl vinyl isonitriles was developed, providing a modular route to bis-β-carbolines, bis-γ-carbolines, and their chalcogen analogues.
- Indoles,
- C−N bond cleavage,
- Metal-free,
- Biheteroaryls,
- Isonitriles
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