Gold-catalyzed indole ring synthesis

In a relatively short time span, gold-catalyzed reactions have blossomed into a powerful new methodology in organic synthesis. Given several reviews in the period 2011 throngh 2014 on gold-catalyzed indole synthesis [1-4], this chapter focuses on a few seminal papers and then very recent work. 

Indole Ring Synthesis From Natural Products to Drug Discovery, First Edition. Gordon W. Gribble. 2016 John Wiley Sons, Ltd. Published 2016 by John Wiley Sons, Ltd. 

A/-Mepyrrole, A/-TIPSpyrrole, n-BuOH, allyl alcohol, indoles 

3-difluoro-2-substituted indolenines and 2-aryl-3-fluoroindoles via a one-pot Au-catalyzed aminofluorina-tion of o-alkynylanilines with Selectfluor [36]. 

The gold-catalyzed chemistry presented in this chapter utilizes a variety of gold catalysts, but all are either gold(I) or gold(III) species. A common feature is that gold salts have an enormous affinity for multiple bonds and they behave as soft carbophiUc Lewis acids, thus triggering subsequent chemistry. For excellent discussions of these mechanisms, see references [42- 8]. 

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