Abstract
The oxiranyl anion is a very unstable nucleophilic epoxide. This previously uncommon nucleophile has now been used for the synthesis of polycyclic ethers. Alkylation of an oxiranyl anion, a three‐carbon building block, with a triflate derived from tetrahydropyran‐methanol followed by acid‐catalyzed 6‐endo cyclization provides a trans‐fused bicyclic compound. Reiterative application of this procedure enables the rapid construction of trans‐fused polytetrahydropyrans.