Synthesis of Structurally Diverse 2,3-Fused Indoles Via Microwave-Assisted AgSbF6-Catalysed Intramolecular Difunctionalization of O-Alkynylanilines

Overview

Journal Sci Rep

Specialty Science

Date 2015 Aug 28

PMID 26310858

Authors

Yuanqiong Huang

Yan Yang

Hongjian Song

Yuxiu Liu

Qingmin Wang

Affiliations

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Abstract

2,3-Fused indoles are found in numerous natural products and drug molecules. Although several elegant methods for the synthesis of this structural motif have been reported, long reaction times and harsh conditions are sometimes required, and the yields tend to be low. Herein, we report a microwave method for straightforward access to various types of 2,3-fused indoles via AgSbF6-catalysed intramolecular difunctionalization of o-alkynylanilines. AgSbF6 played a role in both the hydroamination step and the imine-formation step. This method, which exhibited excellent chemoselectivity (no ring-fused 1,2-dihydroquinolines were formed), was used for formal syntheses of the natural products conolidine and ervaticine and the antihistamine drug latrepirdine.

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