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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 22 (1995), S. 119-130 
    ISSN: 1573-1111
    Keywords: Calixarene ; complexation ; crystal structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A new method is described for the synthesis of isolatedp-tert-butyldihomooxacalix[4]arene (CALO) with a 24% yield. The ability of CALO to form complexes in the solid state with small neutral molecules has been studied; the potential guests were common solvents bearing various chemical functions. The powder obtained after evaporation of the solvent has been characterized by the X-ray powder diffraction technique. Analysis of the patterns shows the non-complexation of linear alkanes and alcohols, but formation of complexes when the guest is cyclic or when it bears an amine or a ketone function. As illustration of the possible arrangement of molecules in complexes, the structure of the 1:2 complex with tetrahydrofuran (THF) is presented: the crystals are monoclinic, space groupP21/c,a=9.459(2) Å,b=17.286(2) Å,c=30.469(6) Å, β=92.52(2)o,V=4977(2) Å3,Z=4,D c=1.099 Mg m−3, λ=1.54178 Å, μ=5.6 cm−1,R=0.086 for 3590 reflections withF〉4σ (F); one of the THF molecules is inside the cavity of the macrocycle, while the other, in the interhost space, exhibits disorder. In the CALO molecule, three out of the fourtert-butyl groups are disordered which may induce the disorder of the THF molecule.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 14 (1992), S. 247-256 
    ISSN: 1573-1111
    Keywords: Inclusion compounds ; calixarene ; crystal structure ; hydrogen bonding ; amines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The structure of thep-t-butyldihomooxacalix[4]arene triethylamine (1 : 2 complex has been determined by X-ray crystallography. Crystals are monoclinic, space groupCc,a = 22.821(3),b = 15.257(3),c = 16.365(2) Å,β = 97.44(1)°,V = 5650(1) Å3,Z = 4,D calc = 1.03 g cm−3. One triethylamine (Et3N) molecule has one of its ethyl groups pointing inside the cavity of a calixarene molecule; its nitrogen atom is directed exo to this calixarene molecule and is involved in a hydrogen bond with one of the hydroxy groups of a neighbouring calixarene molecule. This scheme leads to columns of alternating host and guest molecules. The other Et3N molecule is in the interhost space. This feature allows us to define the title compound as a complex/clathrate hybrid.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 29 (1997), S. 175-185 
    ISSN: 1573-1111
    Keywords: p-tert-Butylcalix[5]arene ; synthesis ; complexation ; crystal structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The formation of p-tert-butylcalix[5]arene by the opening ofp-tert-butyldihomooxacalix [4]arene and the addition of a monomer has beenstudied. Various facets, including the effects of bases and the nature ofthe monomer added to the p-tert-butyldihomooxacalix[4]arene, have beeninvestigated. p-tert-Butylcalix[5]arene can be prepared in yields up to30%. The structure of its 1 : 2 complex with DMF has been determinedby X-ray crystallography. Crystals are triclinic, space group P¯1, a =1428.2(3) pm, b = 1837.3(3) pm, c = 1276.1(2) pm, α = 108.98(1)°,β = 105.02(2)°, γ = 95.21(1)°, Z = 2, D c = 1.059 kg m-3,final R value = 0.087. The macrocycle adopts a cone conformation, one guestenclosed inside the cavity, the other one outside.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 9 (1990), S. 153-160 
    ISSN: 1573-1111
    Keywords: Crown ether ; phenol-alcohol ; crystal structure ; hydrogen bonding ; host-guest complex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Single crystal X-ray analysis of the 1 : 4 complex between 18-crown-6 and 2-hydroxymethyl-4-(1,1,3,3-tetramethylbutyl)phenol is reported. Crystals of the complex are triclinic $$P\bar 1$$ witha = 11.929 (2),b = 18.655(2),c = 8.313(1)Å,α = 93.14(1),β = 94.02(1),γ = 100.89(1)o, andD c = 1.111 g cm−3 forZ = 1. TheR index is 0.057 for 5935 reflections measured at 293 K. The complex lies on a center of symmetry, the macroring has the Ci symmetry (g + g + aag − aag − ag − g − aag + aag + a). The CH2-OH group at theortho position to the phenolic OH lies near the benzene ring plane; this conformation differs from the one found for uncomplexed phenol-alcohol molecules. The packing is characterized by layers of hydrogen bonded entities parallel toac; alongb the layers are stabilized by van der Waals interactions.
    Type of Medium: Electronic Resource
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