Octakis[4-(2-phenylpropan-2-yl)phenylthio]naphthalene: a conformationally unique host allowing direct observation of a well-defined solid-state acetone conformation

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Gary A. Downing, David D. MacNicol and Christopher S. Frampton


Abstract

In its stoichiometric 1:1 clathrate with acetone, studied by X-ray diffraction at 123 K, the title host molecule possesses a unique abbbabbb conformation with six side-chain units anti-parallel to the other two; the guest acetone’s conformation exhibits non-crystallographic C2 symmetry, and the observed lowering in symmetry from C2v in the vapour is accompanied by a significant opening of the guest’s C–C–C angle, in accord with a key theoretical prediction in the literature (J. Chem. Phys., 1993, 98, 2754).


References

  1. For a review see, D. D. MacNicol and G. A. Downing, in Comprehensive Supramolecular Chemistry, ed. D. D. MacNicol, F. Toda and R. Bishop, Pergamon, Oxford, 1996, vol. 6, ch. 14, pp. 434–444 Search PubMed.
  2. G. A. Downing, C. S. Frampton, J. H. Gall and D. D. MacNicol, Angew. Chem., Int. Ed. Engl., 1996, 35, 1547 CrossRef CAS.
  3. Unsolvated crystals of 1 were obtained on recrystallisation of 1 from neat DMF, DMSO, CH2Cl2, 1,4-dioxane, and other solvents.
  4. T. Iijima, Bull. Chem. Soc. Jpn., 1972, 45, 3526 CAS see also J. M. Vacherand, B. P. Van Eijck, J. Burie and J. Demaison, J. Mol. Spectosc., 1986, 118, 355 Search PubMed.
  5. Y. G. Smeyers, M. L. Senent, V. Botella and D. C. Moule, J. Chem. Phys., 1993, 98, 2754 CrossRef CAS and references cited therein.
  6. With regard to the crystalline state, 1109 X-ray crystal structure analyses have been reported for systems in which acetone is present as a ligand component coordinated to a metal (e.g.R. Amstutz, J. D. Dunitz, T. Laube, W. B. Schweizer and D. Seebach, Chem. Ber., 1986, 119, 434; M. Hoyer and H. Hartl, Z. Anorg. Allg. Chem., 1992, 612) or is ‘anchored’ in the lattice by one or more hydrogen bonds (e.g.C. P. Brock and G. L. Morelan, J. Phys. Chem., 1986, 90, 5631). Both these situations tend to attenuate thermal motion, favouring direct observation of the acetone's hydrogen atoms, but represent relatively strong host—guest intcractions. When such motion-reducing interactions are absent, the acetone molecule normally exhibits high thermal motion and/or disorder, however, see for example, A. Dietrich, K. A. Fidelis, D. R. Powell, D. van der Helm and D. L. Eng-Wilmot, J. Chem. Soc., Dalton Trans., 1991, 231; A. Avdeef and W. P. Scheafer, J. Am. Chem. Soc., 1976, 98, 5153. Interestingly, no X-ray results from the molecular crystal of acetone itself have yet appeared in the literature Search PubMed.
  7. For a recent review of C–H⋯O interactions see, T. Steiner, Chem. Commun., 1997, 727 Search PubMed.
  8. J. Cosier and A. M. Glazer, J. Appl. Crystallogr., 1986, 19, 105 CrossRef CAS.
  9. G. M. Sheldrick, Acta Crystallogr., Sect. A., 1990, 46, 467 CrossRef.
  10. G. M. Sheldrick, SHELXL-93, program for the refinement of crystal structures, University of Göttingen, Germany, 1993.
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