The structures of macrocyclic heterocyclophane inclusion complexes
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Crystal and molecular structures of (1:1) molecular complexes of N,N′,N″,N″-tetramethyl-2, 11, 20, 29-tetraaza [18.104.22.168] paracyclophane (1) with CHCl3, CH2Cl2, CH3CN and CO2 are reported. The macrocycle has square-box structure, giving hydrophobic cavity surrounded by four benzene rings. The guest molecules are included in the cavity. The uncomplexed1 was found to have a rectangular form, indicating large conformational flexibility of1. In solution,1 is achiral because rapid R⇌S interconversion, but in solid, the macrocyclic conformation is frozen as “R”-conformer or “S”-conformer. The macrocycles with the same chirality are stacked alongb-axis to form chiral molecular columns, “R”-colums or “S”-columns. Complexes of1 crystallize differently depending on the guest molecules. “R”-columns (“S”-columns) packed alonga-axis produce “R”-layers (“S”-layers), which are further packed alongc-axis using “R”-layer to “R”-layer contact (RR) or SS and RS or SR. The crystals of1·CHCl3 are formulated as--RRR--=[R]n (Type I, chiral) and those of1·CH3CN or1·CO2 and1·CH2Cl2 are represented by [RS]n (Type IIA, racemic) and [RRSS]n (Type IIB, racemic), respectively.
KeywordsBenzene CH2Cl2 Benzene Ring Inclusion Complex CH3CN
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- 1.(a)M.L. Bender and M. Komiyama,Cyclodextrin Chemistry, Springer-Verlag: West Berlin and Heidelberg, 1978.Google Scholar
- 1.(b)I. Tabushi,Acc. Chem. Res., 1982,15, 66.Google Scholar
- 2.(a)I. Tabushi, Y. Kimura, K. Yamamura,J, Am. Chem. Soc., 1981,103, 6486.Google Scholar
- 2.(b)Y. Murakami, A. Nakano, R. Miyata and Y. Matsuda,J. Chem. Soc., Perkin Trans. 1,1979, 1669.Google Scholar
- 3.I. Tabushi, Y. Kuroda and Y. Kimura,Tetrahedron Lett.,1976, 3327.Google Scholar
- 4.I. Tabushi, K. Yamamura, H. Nonoguchi, K. Hirotsu and T. Higuchi,J. Am. Chem. Soc., 1984,106, 2621.Google Scholar
- 5.S.J. Abott, A.G.M. Barret, C.R.A. Godfrey, S.B. Kalindjian, G.W. Simpson and D.J. Williams,J. Chem. Soc., Chem. Commun.,1982, 796.Google Scholar
- 6.Crystals of uncomplexed1 are monoclinic, space group P21/a witha=21.491 (2),b=15.123 (1),c=10.020 (1) Å and β=97.26(1)o; Z=4. The structure was solved by direct method and refined to R=0.083 for 1269 reflections with I>3σ(I). Full details will be published elsewhere.Google Scholar
- 7.The following library of major crystallographic programs was employed: MULTAN, G. Germain, P. Main and M.M. Woolfson,Acta Crystallogr., 1970, B26, 274; ORFLS, W.R. Busing, K.O. Martin and H.A. Levy, Oak Ridge National Laboratory Report ORNL-TM-305; ORTEP, C.K. Johnson, Oak Ridge National Laboratory Report ORNL-TM-3794.Google Scholar
- 8.W.C. Hamilton,Acta Crystallogr., 1959,12, 609.Google Scholar
- 9.N.L. Allinger,J. Am. Chem. Soc., 1977,99, 8127. MM2 is available from Indiana University's Quantum Chemistry Program Exchange as program number 395.Google Scholar