Indole-derived arynes and their Diels-Alder reactivity with furans

Org Lett. 2007 Oct 11;9(21):4135-7. doi: 10.1021/ol701595n. Epub 2007 Sep 19.

Abstract

Arynes derived from any position of the ubiquitous indole nucleus are unknown. We have now provided the first evidence for the formation and trapping of the 4,5-, 5,6-, and 6,7-indolynes. A series of o-dihalo indoles (Cl, Br, F) were synthesized and reacted under metal-halogen exchange conditions to give Diels-Alder cycloadducts in high yield with furan. The use of an excess of tert-butyllithium resulted in the rearrangement of the initially formed cycloadduct; however, employing only a slight excess of n-butyllithium cleanly gave cycloadducts with furan.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Alkynes / chemistry*
  • Benzene Derivatives / chemistry*
  • Furans / chemistry*
  • Heterocyclic Compounds, 2-Ring / chemistry*
  • Indoles / chemical synthesis*
  • Indoles / chemistry*
  • Molecular Structure
  • Stereoisomerism

Substances

  • Alkynes
  • Benzene Derivatives
  • Furans
  • Heterocyclic Compounds, 2-Ring
  • Indoles
  • benzyne