Et3N-induced demethylation-annulation of 3-alkynyl-4-methoxy-2-pyridones and structurally related compounds in the synthesis of furan-fused heterocycles

J Org Chem. 2008 Nov 7;73(21):8619-22. doi: 10.1021/jo8014038. Epub 2008 Oct 3.

Abstract

Various 3-iodo-4-methoxypyridin-2-ones and related pyrone and coumarin derivatives have been demonstrated as readily available precursors of 2-substituted furan-fused heterocycles by means of in situ sequential Sonogashira-acetylide coupling, dealkylation, and regioselective furan annulation reactions. A Et3N-induced S(N)2 process has been established that accounts for the dealkylation process.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Coumarins
  • Ethylamines
  • Furans / chemistry*
  • Heterocyclic Compounds / chemistry*
  • Pyridones / chemistry*
  • Pyrones

Substances

  • Coumarins
  • Ethylamines
  • Furans
  • Heterocyclic Compounds
  • Pyridones
  • Pyrones
  • furan
  • triethylamine