Gold-Catalyzed Intramolecular Tandem Cyclization of Indole-Ynamides: Diastereoselective Synthesis of Spirocyclic Pyrrolidinoindolines

• Published in: Chemistry, an Asian journal an Asian journal, 2016-02, Vol.11 (3), p.371-375
• Main Authors: Zheng, Nan, Chang, Yuan-Yuan, Zhang, Li-Jie, Gong, Jian-Xian, Yang, Zhen
• Format: Article
• Language: English
• Subjects: 1,5-hydride shif; 5-hydride shif; Alkaloids - chemistry; Catalysis; Chemistry; Cyclization; cyclizationt; diastereoselectivity; gold; Gold - chemistry; Indoles - chemistry; Spiro Compounds - chemistry; spirocyclic pyrrolidinoindoline; Stereoisomerism
• ISSN: 1861-4728; 1861-471X
• DOI: 10.1002/asia.201500865

A gold‐catalyzed intramolecular tandem cyclization of indole‐ynamide affords tetracyclic spirocyclic pyrrolidinoindoline bearing an all‐carbon quaternary stereocentre in a single step; however, when the reaction was carried out in the presence of BF3⋅Et2O, the corresponding tricyclic spirocyclic pyrrolidinoindoline‐based enones are produced through a key 1,5‐hydride shift. The developed chemistry provides a diastereoselective and straightforward entry to structurally diverse polycylic pyrrolidinoindolines from indole‐ynamides in one‐pot reactions under mild conditions. A gold‐catalyzed intramolecular tandem cyclization of indole‐ynamide affords tetracyclic spiro‐pyrrolidinoindolines bearing an all‐carbon quaternary stereocentre in a single step. In the presence of BF3⋅Et2O, the corresponding tricyclic spiro‐pyrrolidinoindoline‐based enones are synthesized through a key 1,5‐hydride shift. This method provides a diastereoselective and straightforward entry to structurally diverse polycylic pyrrolidinoindolines.