Abstract
Changes of the interplanar angle in [2.2]metacyclophanes can be achieved by increasing the steric strain between the axial position at C-1 and H-8 as well as between the equatorial position and H-14 and H-12 resp.: These non bonded interactions are relieved by changing the torsional and bond angles with consequent rotation of one aromatic ring about an axis bisecting C-1 and C-10. This has been demonstrated with the aid of acetals4–10 derived from 1,10-dioxo-[2.2]-metacyclophane (13).
The conformational changes were deduced from the chemical shift difference between the intraanular protons 8 and 16 in the1H-NMR spectrum as well as from an increase in allylic coupling of the axial proton at C-2 with H-8.
For these investigations the1H-NMR correlation of the protons of the bridge was indispensable. This problem was solved by deuterium labelling experiments and application of the INDOR-sweep technique on theABX-system of (e,e)-dihydroxy-[2.2]metacyclophane (2).
Similar content being viewed by others
Literatur
R. Bucourt, in: Topics in Stereochemistry (N. L. Allinger undE. L. Eliel, Hrsg.), Bd.8, S. 169, 1974;E. L. Eliel, N. L. Allinger, S. L. Angyal undG. A. Morrison, Conformational Analysis. Wiley-Interscience. 1965.
H. Lehner, Mh. Chem.105, 895 (1974).
C. Glotzmann, E. Langer undH. Lehner, Mh. Chem.105, 354 (1974).
E. Langer undH. Lehner, Tetrahedron Letters1974, 1357.
R. A. Hoffmann, S. Forsen undB. Gestblom, in: NMR-Grundlagen und Fortschritte (P. Diel, E. Fluck undR. Kosfeld, Hrsg.) Bd. 5. Berlin-Heidelberg-New York: Springer. 1971.
M. P. Williamson, R. J. Kostelnik undS. M. Castellano, J. Chem. Phys.49, 2218 (1968).
R. J. Spear undS. Sternhell, Tetrahedron Letters1973, 1487.
S. Sternhell, Quart. Rev.23, 236 (1969).
J. W. Emsley, J. Feeney undL. H. Sutcliffe, High Resolution Nuclear Magnetic Resonance Spectroscopy, Bd. 1 und 2. Pergamon Press. 1965.
A. J. De Kok undC. Romers, Rec. Trav. Chim.89, 313 (1970).
L. B. Brahde, Acta Chem. Scand.8, 1145 (1954).
S. Furberg undO. Hassel, Acta Chem. Scand.4, 1584 (1950).
H. T. Kalff undC. Romers, Acta Cryst.20, 490 (1966).
Handbook of Chemistry and Physics, 45. Aufl. Cleveland, Ohio: The Chemical Rubber Co. 1964.
E. L. Eliel undL. A. Pilato, Tetrahedron Letters1962, 103;M. P. Mertes, J. Org. Chem.28, 2320 (1963);E. L. Eliel, E. W. Della undM. Rogić, J. Org. Chem.30, 855 (1965).
T. Hylton undV. Boekelheide, J. Amer. Chem. Soc.90, 6887 (1968).
H. W. Gschwend, J. Amer. Chem. Soc.94, 8430 (1972).
Author information
Authors and Affiliations
Additional information
Mit 10 Abbildungen
2. Mitt.:E. Langer undH. Lehner, Mh. Chem.106, 175 (1975).
Rights and permissions
About this article
Cite this article
Glotzmann, C., Haslinger, E., Langer, E. et al. Gezielte Konformationsänderungen an cyclischen Systemen, 3. Mitt.: Konformationsänderungen durch “Non-Bonded Interactions” in [2.2]Metacyclophanen. Monatshefte für Chemie 106, 187–201 (1975). https://doi.org/10.1007/BF00914512
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00914512