Flexible Synthesis of Benzofuranones from ortho‐Alkynyl Phenols or Benzofurans

Abstract

AbstractBenzofuranones are attractive synthetic targets in medicinal and natural products. The cycloisomerization of o‐alkynyl phenol to benzofuran‐3(2H)‐one is reported here using gold(I) and Selectfluor. This benzofuranone can also be obtained from benzofuran without a gold catalyst. This study presents two appealing synthetic methods for benzofuran‐3(2H)‐ones that use readily available starting materials, have high chemoselectivity and operate under very mild conditions.