2. Academic Validation
  3. 5-Hydroxyindoles by intramolecular alkynol-furan diels-alder cycloaddition

5-Hydroxyindoles by intramolecular alkynol-furan diels-alder cycloaddition

  • J Org Chem. 2013 Jan 4;78(1):167-74. doi: 10.1021/jo3022605.
Matthew LaPorte 1,  Ki Bum Hong,  Jie Xu,  Peter Wipf
Affiliations

Affiliation

  • 1 Department of Chemistry and Center for Chemical Methodologies & Library Development, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
PMID: 23136970 DOI: 10.1021/jo3022605
Abstract

A convergent approach provides a convenient access to synthetically and biologically useful 3,4-disubstituted 5-hydroxyindoles. The one-pot procedure uses microwave heating to initiate an intramolecular [4 + 2]-cycloaddition of an alkynol segment onto a furan followed by a fragmentation, aromatization, and N-Boc deprotection cascade. Yields range from 15 to 74%, with aromatic substituents providing better conversions. 4-Trimethylsilylated analogues undergo a 1,3-silatropic rearrangement to give the O-TMS ethers.

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