Preparation of Indoles from o -Alkynyltrifluoroacetanilides Through the Aminopalladation­-Reductive Elimination Process

Abstract

The functionalized pyrrole nucleus contained in the indole system has been assembled via the palladium-catalyzed reaction of o-alkynyltrifluoroacetanilides with organic halides/triflates or allyl carbonates. In the presence of carbon monoxide, a three-component reaction can take place and indole derivatives incorporating a molecule of carbon monoxide have been obtained.

Key words

indoles - alkynes - cyclization - palladium - catalysis

References

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5

o-Ethynyltrifluoroacetanilide can be prepared in 70% overall yield from commercially available o-iodoaniline via a three-step process as described in Ref.³