Sulfoxide-Directed Intramolecular [4+2] Cycloadditions between 2-Sulfinyl Butadienes and Unactivated Alkynes

Sulfinyl dienynes undergo thermal and catalyzed IMDA cycloadditions, often at room temperature, to produce cyclohexa-1,4-dienes with good yields and high selectivities. Additionally, the products preserve a synthetically useful vinyl sulfoxide functionality. The selective manipulation of the double bonds in the cycloadducts has also been examined in this work.