Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Abteilungen OPUS4-4070 Wissenschaftlicher Artikel Bringmann, Gerhard; Hartung, Thomas; Goebel, Lothar; Schupp, Olaf; Ewers, Christian L. J.; Schoener, Bernd; Zagst, Rainer; Peters, Karl; Von Schnering, Hans Georg; Burschka, Christian Novel concepts in directed biaryl synthesis, IX: Synthesis and structure of benzonaphthopyranones, useful bridged model precursors for stereoselective biaryl syntheses A practicable two-step procedure for the preparation of a series of lactone-type bridged biaryls 7 as favorable substrates for subsequent atropisomer-selective ring-opening reactions is described. Due to the efficiency of the coupling step, which tolerates even a telt·butyl group next to the biaryl axis and avoids problems of regioselectivity, a variety of differently substituted representatives is prepared. These cover a broad range of steric hindrance and thus molecular distortion. The structures are investigated mainly by NMR spectroscopy and X-ray diffraction, showing the lactones 7 to be helically distorted, depending on the size of the residues R. 1992 urn:nbn:de:bvb:20-opus-46635 Institut für Anorganische Chemie