Facile access to 4-(1-alkynyl)-2(5H)-furanones by Sonogashira coupling of terminal acetylenes with β-tetronic acid bromide: efficient synthesis of cleviolide

A mild and convenient synthesis of 4-(1-alkynyl)-2(5H)-furanones has been achieved by Sonogashira or Heck-type alkynylation of β-tetronic acid bromide. As an illustration of this methodology, the natural product cleviolide was prepared in two steps and 78% overall yield.