Sonogashira Cross-Coupling Reactions and Construction of the Indole Ring System Using a Robust, Silica-Supported Palladium Catalyst

Abstract

The use of a recyclable silica-supported palladium catalyst in Sonogashira couplings and indole syntheses using a range of functionalised substrates is described. The catalyst is shown to be both robust and versatile, effecting the synthesis of 2-phenylindole in quantitative yield without the need for N-protection, a copper cocatalyst, a base, or a solvent.

Sonogashira cross-coupling - silica-supported catalysis - palladium catalyst - indoles - enynes

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