R ₃ P/ICH ₂ CH ₂ I-Promoted Skeletal Editing of Cyclic Ethers via O/N Exchange

The functionalization of cyclic ethers has received significant attention; however, the skeletal editing of cyclic ethers via O-to-N exchange remains challenging. Herein, we report a R₃P/ICH₂CH₂I-promoted O-to-N exchange of cyclic ethers. This strategy enables the direct conversion of widely available cyclic ethers─such as tetrahydrofuran and 1,4-dioxane─into nitrogen-containing heterocycles, structural motifs commonly found in biologically active molecules. The method exhibits broad compatibility with secondary and tertiary amines, delivering the corresponding products in moderate to good yields.