Investigation of the Synthesis of Benzofuroindolines from N-Hydroxyindoles: An O-Arylation/[3,3]-Sigmatropic Rearrangement Sequence

Dedicated to Dr. Patrick Y. S. Lam

Abstract

We report the demonstration that sensitive N-hydroxyindoles can be O-arylated under transition-metal-free conditions with biaryliodonium salts. The subsequent spontaneous [3,3]-sigmatropic rearrangement delivers benzofuroindolines derived from tryptamine. We also describe the practical synthesis of N-hydroxyindoles by oxidation of indolines with m-CPBA.

Key words

N-hydroxyindoles - diazonamide A - azonazine - benzofuroindoline - [3,3]-sigmatropic rearrangement

• References and Notes

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