Abstract
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.
Similar content being viewed by others
References
C. J. Pedersen:J. Am. Chem. Soc. 89, 2495–2496 (1967).
C. J. Pedersen:J. Am. Chem. Soc. 89, 7017–7036 (1967).
D. J. Cram, T. Kaneda, R. C. Helgeson, and G. M. Lein:J. Am. Chem. Soc. 101, 6752–6754 (1979).
D. J. Cram, T. Kaneda, R. C. Helgeson, S. B. Brown, C. B. Knobler, E. Maverick and K. N. Trueblood:J. Am. Chem. Soc. 107, 3645–3657 (1985).
K. N. Trueblood, E. F. Maverick and C. B. Knobler:Acta Crystallogr. B47, 389–398 (1991).
D. J. Cram, G. M. Lein, T. Kaneda, R. C. Helgeson, C. B. Knobler, E. Maverick, and K. N. Trueblood:J. Am. Chem. Soc. 103, 6228–6232 (1981).
C. E. Strouse:Rev. Sci. Instr. 47, 871–876 (1976).
G. M. Sheldrick:SHELX76, Program for crystal structure determination. University of Cambridge, England (1976).
D. T. Cromer and J. B. Mann:Acta Crystallogr. A24, 321–324 (1968).
R. F. Stewart, E. R. Davidson, and W. T. Simpson:J. Chem. Phys. 42, 3175–3187 (1965), as employed inSHELX76 [8].
P. Main, S. E. Hull, L. Lessinger, G. Germain, J. P. Declercq, and M. M. Woolfson:MULTAN78, A System of Computer Programs for the Automatic Solution of Crystal Structures from X-ray Diffraction Data. Univ. of York, England (1978).
UCLA Crystallographic Package: J. D. McCullough Laboratory of X-ray Crystallography, Univ. of California, Los Angeles, (1984).
W. D. S. Motherwell and W. Clegg:PLUTO78. A program for drawing crystal and molecular structures. Univ. of Cambridge, England (1978).
K. N. Trueblood:Acta Crystallogr. A34, 950–954 (1978); J. D. Dunitz, V. Schomaker and K. N. Trueblood:J. Phys. Chem. 92, 856–867 (1988).
W. C. Hamilton:Acta Crystallogr. 12, 609–610 (1959).
P. A. Kollman, G. Wipff and U. C. Singh:J. Am. Chem. Soc. 107, 2212–2219 (1985).
K. Hermansson, J. O. Thomas, and I. Olovsson:Acta Crystallogr. B33, 2857–2861 (1977).
C. A. Reiss, K. Goubitz and D. Heijdenrijk:Acta Crystallogr. C46, 465–467 (1990).
R. D. Shannon:Acta Crystallogr. A32, 751–767 (1976).
D. J. Cram and G. M. Lein:J. Am. Chem. Soc. 107, 3657–3668 (1985).
F. L. Hirshfeld:Acta Crystallogr. A32, 239–244 (1976).
R. E. Rosenfield, K. N. Trueblood, and J. D. Dunitz:Acta Crystallogr. A34, 828–829 (1978).
F. H. Allen, O. Kennard, D. G. Watson, L. Brammer, A. G. Orpen and R. Taylor:J. Chem. Soc. Perkin Trans. 2, S1–S19 (1987).
Author information
Authors and Affiliations
Additional information
This paper is dedicated to the memory of the late Dr C. J. Pedersen.
Rights and permissions
About this article
Cite this article
Knobler, C.B., Maverick, E. & Trueblood, K.N. The crystal and molecular structures of bridged spherands: The host C52H52O8, its complex C52H52O8·Li+, and the complexes C50H48O6·Li+ and C52H52O6·Li+ . J Incl Phenom Macrocycl Chem 12, 341–360 (1992). https://doi.org/10.1007/BF01053873
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01053873