Ruthenium-Catalyzed Carbonylative Cycloaddition of α-Keto Lactones with Alkenes or Alkynes:  The Participation of an Ester-Carbonyl Group in Cycloaddition Reactions as the Two-Atom Assembling Unit

Abstract

The reaction of benzofuran-2,3-dione derivatives 1 with CO and alkenes (or alkynes) results in a carbonylative [2+2+1] cycloaddition in which the ester-carbonyl group is incorporated into a two-atom assembling unit to give spirolactone derivatives 2. This reaction provides the first example of an ester-carbonyl group participating in a carbonylative cycloaddition reaction.