Enantioselective Synthesis, (Chir)optical Properties, and Postsynthetic Functionalization of Furan-Containing Oxa[5]-, Oxa[6]-, and Dioxa[6]helicenes

Open AccessCCS ChemistryRESEARCH ARTICLES24 May 2024Enantioselective Synthesis, (Chir)optical Properties and Post-synthetic Functionalization of Furan-containing Oxa[5]-, Oxa[6]-, and Dioxa[6]helicenes Wei Fu, Valentina Pelliccioli, Raquel Casares-López, Juan M. Cuerva, Martin Simon, Christopher Golz and Manuel Alcarazo Wei Fu , Valentina Pelliccioli , Raquel Casares-López , Juan M. Cuerva , Martin Simon , Christopher Golz and Manuel Alcarazo https://doi.org/10.31635/ccschem.024.202404088 SectionsSupplemental MaterialAboutPDF ToolsAdd to favoritesDownload CitationsTrack Citations ShareFacebookTwitterLinked InEmail An expedient synthesis of a series of configurationally stable oxa[5]helicenes, oxa[6]helicenes, and dioxa[6]helicenes has been developed using an intramolecular, highly enantioselective, Au-catalyzed, alkyne hydroarylation reaction. The absolute configuration of the newly prepared structures has been established by crystallography, their inversion barriers were determined theoretically and experimentally, and their chiroptical properties have been investigated. Comparison of these data with those reported for thia- or carbohelicenes sharing an otherwise identical helical framework enables the establishment of comprehensive correlations between the nature of the embedded (hetero)atom(s) and the magnitude of these properties. Preliminary studies on the post-synthetic functionalization of the oxahelicenes obtained are also described. Specifically, site-selective bromination at 15-position in oxa[5]helicene 5d allows its subsequent manipulation into pyridine-containing aza-oxa[7]helicene 13d; while the two termini of oxa[6]helicene 7d have been intramolecularly cyclised into the pleiadeno[1,12,11-bcde]benzofuran derivative 15d by acidic treatment. Both transformations took place without erosion of the enantiopurity. Download figure Download PowerPoint Previous articleNext article FiguresReferencesRelatedDetails Issue AssignmentNot Yet AssignedSupporting Information Copyright & Permissions© 2024 Chinese Chemical Society Downloaded 0 times PDF downloadLoading ...