• The first stage of the reaction is simple tautomerism.
• The final step of this reaction follows the E2 reaction mechanism.
• Intramolecular reaction is, of course, vital to the heterocycle formation.
• The same starting material can be used to form pyrroles or thiophenes.
  
  
  References:
• Amarnath V.; Amarnath K.; Journal of Organic Chemistry, 1995, Volume 60. Issue 2, 301-307
• Minetto G.; Raveglia L.F.; Taddei M.; Organic Letters, 2004, Volume 6, Issue 3, 389-392