<> "The repository administrator has not yet configured an RDF license."^^ . <> . . "Strategies to Circulene Precursos by Inside-out and Outside-in Shotgun Approaches"^^ . "In the context of this thesis, two synthetic strategies towards [2n]circulenes, a class of polycyclic\r\naromatic hydrocarbons (PAHs) were developed, that correspond to an inside-out and outside-in approach.\r\n\r\nFor the inside-out approach, where the n-membered central ring is constructed first, a\r\npalladium-catalyzed oligomerization of Kobayashi-aryne precursors was successfully applied to\r\ntert-butylated pyrene. The resulting di- to pentapyrenylenes incorporated two to five [5]-helicene\r\nmoieties. Optimization of reaction parameters to increase the yield of tripyrenylene was successful and\r\nenabled conformational investigation as well as postfunctionalization. X-ray structural analysis of the\r\ntripyrenylene after prolonged heating confirmed the expectation of a conformational change to the chiral\r\nD3-symmetry, which is configurationally stable, as proven by both kinetic and quantum mechanical\r\nstudies. Chiral-HPLC purification in combination with successful postfunctionalization by K-region\r\noxidation and -extension by aromatic ortho-diamines, lay the foundation for easy to modify\r\nenantiopure propeller PAHs.\r\n\r\nThe inverse approach of constructing the periphery of the circulene in the beginning and closing the ring\r\nafterwards was investigated by a Suzuki-coupling of a suitable borylated ortho-terphenylene and\r\northo-halogenated veratrole building block in a 1:1 ratio. Because of this shotgun approach, an\r\noligomeric series of cyclo-ortho-para-phenylenes (n-COPPs) up to [40]-COPP were observed in\r\nMALDI mass spectrometry and up to [24]-COPP isolated by elaborate purification methods involving\r\nrec-GPC. Conformational analysis of the [n]-COPPs was possible due to variable temperature NMR\r\nexperiments and quantum mechanical studies. Subsequent cyclization by Scholl- or photocyclizations\r\ntowards the [n]circulenes generated novel PAHs. Their constitution was elucidated by thorough 2DNMR\r\nanalysis coupled with quantum mechanical studies and their optical properties were investigated."^^ . "2026" . . . . . . . "Dennis"^^ . "Popp"^^ . "Dennis Popp"^^ . . . . . . "Strategies to Circulene Precursos by Inside-out and Outside-in Shotgun Approaches (PDF)"^^ . . . "Strategies to Circulene Precursos by Inside-out and Outside-in Shotgun Approaches (Other)"^^ . . . . . . "Strategies to Circulene Precursos by Inside-out and Outside-in Shotgun Approaches (Other)"^^ . . . . . . "Strategies to Circulene Precursos by Inside-out and Outside-in Shotgun Approaches (Other)"^^ . . . . . . "Strategies to Circulene Precursos by Inside-out and Outside-in Shotgun Approaches (Other)"^^ . . . . . . "Strategies to Circulene Precursos by Inside-out and Outside-in Shotgun Approaches (Other)"^^ . . . . . "HTML Summary of #36838 \n\nStrategies to Circulene Precursos by Inside-out and Outside-in Shotgun Approaches\n\n" . "text/html" . . . "540 Chemie"@de . "540 Chemistry and allied sciences"@en . .