@article{BringmannHartungGoebeletal.1992, author = {Bringmann, Gerhard and Hartung, Thomas and Goebel, Lothar and Schupp, Olaf and Ewers, Christian L. J. and Schoener, Bernd and Zagst, Rainer and Peters, Karl and Von Schnering, Hans Georg and Burschka, Christian}, title = {Novel concepts in directed biaryl synthesis, IX: Synthesis and structure of benzonaphthopyranones, useful bridged model precursors for stereoselective biaryl syntheses}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-46635}, year = {1992}, abstract = {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.}, subject = {Chemie}, language = {en} }