Oxidative Annulation of Anilides with Internal Alkynes Using an (Electron‐Deficient η5‐Cyclopentadienyl)Rhodium(III) Catalyst Under Ambient Conditions

Abstract

AbstractA dinuclear (electron‐deficient η5‐cyclopentadienyl)rhodium(III) complex was synthesized on a preparative scale via the rhodium‐catalyzed cross [2+2+1] cyclotrimerization of silylacetylenes and two alkynyl esters, leading to substituted silylfulvenes, followed by reductive complexation with rhodium(III) chloride in ethanol. The thus obtained dinuclear (electron‐deficient η5‐cyclopentadienyl)rhodium(III) complex is a highly active precatalyst for the oxidative annulation of anilides with internal alkynes under ambient conditions (at room temperature under air). A preference for annulation across electron‐rich substrates over electron‐deficient substrates was observed using this electron‐deficient rhodium(III) complex.magnified image