caa a22 4500 469059125 CHVBK 20180323132852.0 cr unu---uuuuu 170328e19920101xx s 000 0 eng 10.1007/BF01053873 doi (NATIONALLICENCE)springer-10.1007/BF01053873 The crystal and molecular structures of bridged spherands: The host C52H52O8, its complex C52H52O8·Li+, and the complexes C50H48O6·Li+ and C52H52O6·Li+ [Elektronische Daten] [Carolyn Knobler, Emily Maverick, Kenneth Trueblood] The structures of the title novel hosts and host-guest complexes, synthesized by D. J. Cram and his colleagues, were determined by direct methods from diffractometer data and refined by least-squares. The hosts C52H52O8,I, C50H48O6,II, and C52H52O6,III, are di-bridged derivatives of the prototype spherand C48H48O6,IV. InIV, six 4-methylanisole units are joined in the 2,6 positions. InI two -CH2CH2OCH2CH2- bridges replace four of the methoxy methyl groups, joining pseudo-meta oxygen atoms; these two bridges are on the same face of the macrocycle (syn). InII andIII, trimethylene and tetramethylene bridges, respectively, are similarly situated, again replacing four methoxy methyls ofIV. CompoundsIa,IIa andIIIa are Li+ complexes of these hosts. The lithium ion is essentially hepta-coordinated inIa, penta-coordinated inIIa and hexa-coordinated inIIIa. These structures are extremely rigid, and the aromatic rings in them are greatly deformed. There are intramolecular oxygen contacts in each complex only slightly greater than 2.5 Å, about 10 percent shorter than the sum of the usual van der Waals radii for oxygen atoms. Thus the structures provide useful data for parameterizing potential functions for molecular mechanics calculations. Kluwer Academic Publishers, 1992 Intramolecular overcrowding nationallicence crystal structures nationallicence spherand nationallicence Li+ complexes nationallicence host nationallicence guest nationallicence Knobler Carolyn J. D. McCullough Laboratory for X-ray Crystallography, Department of Chemistry and Biochemistry, University of California, 90024, Los Angeles, California, USA aut Maverick Emily J. D. McCullough Laboratory for X-ray Crystallography, Department of Chemistry and Biochemistry, University of California, 90024, Los Angeles, California, USA aut Trueblood Kenneth J. D. McCullough Laboratory for X-ray Crystallography, Department of Chemistry and Biochemistry, University of California, 90024, Los Angeles, California, USA aut Journal of inclusion phenomena and molecular recognition in chemistry Kluwer Academic Publishers 12/1-4(1992-01-01), 341-360 0923-0750 12:1-4<341 1992 12 10847 https://doi.org/10.1007/BF01053873 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF01053873 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Knobler Carolyn J. D. McCullough Laboratory for X-ray Crystallography, Department of Chemistry and Biochemistry, University of California, 90024, Los Angeles, California, USA aut NATIONALLICENCE 700 1- Maverick Emily J. D. McCullough Laboratory for X-ray Crystallography, Department of Chemistry and Biochemistry, University of California, 90024, Los Angeles, California, USA aut NATIONALLICENCE 700 1- Trueblood Kenneth J. D. McCullough Laboratory for X-ray Crystallography, Department of Chemistry and Biochemistry, University of California, 90024, Los Angeles, California, USA aut NATIONALLICENCE 773 0- Journal of inclusion phenomena and molecular recognition in chemistry Kluwer Academic Publishers 12/1-4(1992-01-01), 341-360 0923-0750 12:1-4<341 1992 12 10847 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer