Synthesis of Ring-A-Substituted Tryptophan by a Palladium-Catalyzed Heteroannulation Reaction

Abstract

Coupling of substituted o-iodoanilines with methyl (S)-2-N,N-di-tert-butoxycarbonyl-5-oxo-pentanoate, derived from glutamic acid, in DMF in the presence of palladium acetate and DABCO provides substituted tryptophans in good to excellent yields.

Key words

palladium-catalyzed heteroannulation - indole synthesis - substituted tryptophan

References

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24

l-Try was isolated in 10% yield under Baran’s modified conditions.