Chemistry of acetylenic ethers: 78 Isomerization of some conjugated enyne compounds

Enyne‐hydrocarbons, ‐alcohols and ‐ethers with the system can be converted into the isomers with a terminal acetylenic group , by treating them with an excess of potassium amide in liquid ammonia and hydrolysing the reaction mixture thus formed. In most cases yields are excellent. Enyne thioethers RCC‐CHCH‐SC2H5(R  alkyl) undergo an elimination of ethanethiol under these conditions. Hydrolysis affords the 1,3‐diynes RCC‐CCH in very good yields.