Macrocyclization of 3-triflyloxybenzynes with tetrahydrofuran via an anionic thia-Fries rearrangement

A novel and uncommon macrocyclization reaction between 3-triflyloxybenzynes and tetrahydrofuran has been developed for the first time, providing a direct method for the synthesis of a range of functionalized 19-membered polyether macrocycles in moderate to good yields. The process was proposed to proceed through an anionic thia-Fris rearrangement under transition metal-free conditions, leading to the formation of four new C–O bonds and one new C–S bond in a single step.