Selective Green Coupling of Alkynyltins and Allylic Halides to Trienynes via a Tandem Double Stille Reaction

The palladium-catalyzed reaction of alkynyltin compounds with allylic chlorides leads to a 2:2 coupling to give trienynes by regio- and stereo-selective formation of three new C-C bonds. The reaction can be applied to different alkynyl and allylic fragments, providing a wide range of trienynes with different substitution patterns in very good yields. They can be prepared in a green way using recyclable polymeric tin alkynyls.