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  • 1
    Electronic Resource
    Electronic Resource
    The use of crown ethers to access new M[Al2R6X] species. Synthesis and crystal structure of [K · dibenzo-18-crown-6] [Al2Me6Cl] · 2 C6H6 (1983)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 1 (1983), S. 199-207 
    Details
    ISSN: 1573-1111
    Keywords: crown ether ; liquid clathrate ; aluminum alkyl
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Potassium chloride does not react with trimethylaluminium in benzene in the absence of a crown ether. With the addition of dibenzo-18-crown-6, a normal liquid clathrate ensues. The composition of the parent compound has been established by a single crystal X-ray diffraction study. The space group is monoclinicP21/c with unit cell dimensionsa=21.319(8),b=9.512(4),c=21.081(8) Å, β=93.79(3)°, andρ calc1.15 g cm−3 forZ=4. Refinement led to a final conventionalR value of 0.049 for 2224 observed reflections. The anion has the expected angular geometry (Al−Cl−Al=120.0(1)°). There are two different types of benzene in the crystalline solid. One is associated with the K+ ion, while the other exists in layers normal to thea axis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00656823
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  • 2
    Electronic Resource
    Electronic Resource
    Alternative methods of modifying the calixarene conformation. The synthesis and molecular structures oft-butylcalix[4]arene methyl ether complexed with aluminum alkyl species (1987)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 5 (1987), S. 747-758 
    Details
    ISSN: 1573-1111
    Keywords: Calix[4]arene ; aluminum alkyl ; crystal structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The configurations of calix[4]arenes may be modified by the formation of donor-acceptor complexes which make use of the basicity of the oxygen atoms of the macrocycle. The complex [t-butylcalix[4]arene methyl ether][AlMe3]2,2, exhibits the previously unseen ‘1,2-alternate’ geometry, while [t-butylcalix[4]arene methyl ether][MeAlCl2]2,3, and [t-butylcalix[4]arene methyl ether][EtAlCl2]2,4, show the ‘1,3-alternate’ configuration.2 crystallizes in the triclinic space groupPl witha=11.14(1),b=11.60(1),c=12.02(1) Å, α=77.32(8), β=67.91(8), and γ=69.34(8)o withD c =1.06 g cm−3 forZ=1. Refinement based on 1270 observed reflections led toR=0.106.3 as the benzene solvate belongs to the monoclinic space groupC2/c witha=12.116(2),b=21.557(7),c=23.470(6) Å, and β=104.05(2)o withD c =1.13 g cm−3 forZ=4. Refinement based on 2335 observed reflections led toR=0.075.4 crystallizes in the monoclinic space groupC2/c witha=12.062(4),b=21.175(6),c=21.596(5) Å, and β=100.78(4)o withD c =1.18 g cm−3 forZ=4. Refinement based on 2529 observed reflections gaveR=0.082. The Al-O lengths in all three complexes are normal for donor-acceptor interactions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00656595
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  • 3
    Electronic Resource
    Electronic Resource
    From crown ethers to zeolites: Reaction of EtAlCl2 with crown ethers (1984)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 2 (1984), S. 367-376 
    Details
    ISSN: 1573-1111
    Keywords: crown ether ; liquid clathrate ; aluminum alkyl ; aluminoxane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In contrast to aluminum alkyls, alkyl aluminum halides such as EtAlCl2 react with crown ethers to form cation-anion pairs which exhibit the liquid clathrate effect. Specifically, [12-C-4·AlCl2][AlCl3Et] and [18-C-6·AlCl2][AlCl3Et] have been isolated and characterized by X-ray diffraction techniques. The cations show aluminum in an octahedral environment made up of four of the oxygen atoms from the crown and two chlorine atoms. The 12-C-4 derivative crystallizes in the monoclinic space group P21/c with cell constants of a=7.497(4), b=22.121(8), c=12.339(5) Å, β=94.99(3)o, and Z=4 for ρ=1.43 g cm−3. Least-squares refinement based on 1413 observed reflections led to a final conventional R value of 0.093. The 18-C-6 complex belongs to the triclinic space group P1 with a=8.414(4), b=12.193(6), c=12.394(6) Å, α=73.14(4), β=86.07(4), γ=81.52(4)o, and Z=2 for ρ=1.45 g cm−3. Refinement based on 2605 observed reflections led to R=0.063. The complex aluminum-containing species are related to a class of compounds called aluminoxanes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00663277
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