Bidirectional and Convergent Routes to oligo(Tetrahydrofurans)
摘要:
AbstractOligo(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.