Arene Activation through Iminium Ions: Product Diversity from Intramolecular Photocycloaddition Reactions

Abstract: While 2‐alk‐ω‐enyloxy‐sustituted benzaldehydes do not display any photochemical reactivity at the arene core, the respective iminium perchlorates were found to undergo efficient reactions either upon direct irradiation (λ=366 nm) or under sensitizing conditions (λ=420 nm, 2.5 mol% thioxanthen‐9‐one). Three pathways were found: (a) Most commonly, the reaction led to benzoxacyclic products in which the olefin in the tether underwent a formal, yet unprecedented carboformylation (13 examples, 44–99 % yield). The cascade process occurred with high diastereoselectivity and was found to be stereoconvergent. (b) If a substituent resides in the 3‐position of the benzene ring, a meta photocycloaddition was observed which produced tetracyclic skeletons with five stereogenic centers in excellent regio‐ and diastereoselectivity (2 examples, 58–79 % yield). (c) If the tether was internally substituted at the alkene, an arene photocycloaddition was avoided and an azetidine was formed in an aza Paternò–Büchi reaction (2 examples, 95–98 % yield).

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch

References and Relationships

• Bibliographic citation: Arene Activation through Iminium Ions: Product Diversity from Intramolecular Photocycloaddition Reactions ; day:02 ; month:09 ; year:2022 ; extent:1 ; Angewandte Chemie / International edition. International edition ; (02.09.2022) (gesamt 1)

Contributors, Places and Time

• Creator: Proessdorf, Johanna ; Jandl, Christian ; Pickl, Thomas ; Bach, Thorsten

Further information

• DOI: 10.1002/anie.202208329
• URN: urn:nbn:de:101:1-2022090315075086344610
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 15.08.2025, 7:35 AM CEST