Bidirectional and Convergent Routes to oligo(Tetrahydrofurans)

Abstract

Abstract Oligo(tetrahydrofurans) (oligo‐THFs) 8–12 have been synthesised stereoselectively. Multiple Williamson reactions were used as key steps. While oligo‐THFs with an even number of THF rings like the bi‐THFs 8 and 9 as well as the tetra‐THFs 10 and 11 were obtained by a bidirectional strategy, the penta‐THF 12 with an odd number of THF rings was prepared by a convergent strategy with a sulfone–aldehyde coupling as connecting step. The oligo‐THF products are important structural features of natural (Annonaceae acetogenins) and non‐natural (artificial ion channels) products.