Effect of tether length on endo/exo stereoselectivity in alkene–arene meta‐photocycloaddition reactions towards the Aphidocolin/Stemodin scaffolds

Alshammari, A. A. A., Boyd, J. W., Greaves, N., Kettle, J. G., McKendrick, J. E. ORCID: https://orcid.org/0000-0003-2275-0569, Parker, L. G., Russell, A. T., Sani, A. and Smith, C. D. ORCID: https://orcid.org/0000-0002-5911-5836 (2024) Effect of tether length on endo/exo stereoselectivity in alkene–arene meta‐photocycloaddition reactions towards the Aphidocolin/Stemodin scaffolds. European Journal of Organic Chemistry, 27 (30). e202400463. ISSN 1434-193X doi: 10.1002/ejoc.202400463

Abstract/Summary

Intramolecular alkene-arene meta-photocycloadditions are powerful transformations that use the enhanced reactivity of photoexcited benzene rings to facilitate addition of an alkene 1,3 across donor groups and form complex three-dimensional fused-ring systemsfrom readily accessible starting materials. Intramolecular examples havetraditionallybeen restricted to 3-memberedtethers, with cycloaddition resulting from exo-conformation. However, by judicious tether design we have demonstratedthat a 4-membered tether can also proceed in good yield; interestingly,viaan endo-exciplex(1.2:1) enabling access to both natural product skeletons and interesting scaffolds for medicinal chemistry research.