ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Macrocycle complexation chemistry. 38. Crystallographic and ultraviolet/visible characterization of nitrobenzo-15-crown-5, dinitrobenzo-15-crown-5, and dinitrodibenzo-18-crown-6·2CH3CN (1992)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 13 (1992), S. 219-232 
    Details
    ISSN: 1573-1111
    Keywords: Nitrobenzo-15-crown-5 ; dinitrobenzo-15-crown-5 ; dinitrodibenzo-18-crown-6 acetonitrile solvate ; X-ray crystal structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The crystal structures of three nitrated benzocrown ethers have been determined. Nitrobenzo-15-crown-5 crystallizes in the orthorhombic space group,Pca21, witha = 15.367(2),b = 4.8499(8),c = 19.963(5)Å, andD calc = 1.40 g cm−3 forZ = 4. Dinitrobenzo-15-crown-5 crystallizes in the monoclinic space group,P21/n, witha = 11.716(2),b = 8.495(3),c = 17.441(5)Å,β = 108.40(2)° andD calc = 1.44 g cm−3 forZ = 4.Dinitrodibenzo-18-crown-6·2CH3CN ismonoclinic,P21/n,witha = 8.138(2),b = 20.435(9),c = 15.953(9)Å,β = 100.55(4)° andD calc = 1.36 g cm−3 forZ = 4. The nitro substituents are in the plane of the benzo ring except in the sterically congested dinitrobenzo-15crown-5. The observed crown ether conformations are similar to their substituted analogs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01042780
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    f-Element/crown ether complexes. 27. The synthesis and crystal structure of [Ce(NO3)3 (OH2)(12-crown-4)] -12-crown-4 (1990)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 8 (1990), S. 375-382 
    Details
    ISSN: 1573-1111
    Keywords: 12-crown-4 ; cerium nitrate complex ; X-ray crystal structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A unique cerium nitrate complex, [Ce(NO3)3(OH2)(12-crown-4)]-12-crown-4, has been crystallized from the reaction of hydrated cerium nitrate and 12-crown-4. It crystallizes in the orthorhombic space group,Pnma, with (at −150°C)a = 22.901(5),b = 13.547(3),c = 8.422(1)Å, andD x = 1.77 g cm−3 forZ = 4 formula units. A finalR value of 0.048 was obtained utilizing 2059 unique observed [F o ⩾ 5σ(F o)] reflections. The Ce atom resides on a crystallographic mirror plane and is 11-coordinate, coordinated to three bidentate nitrate groups, one water molecule and the four oxygens of one 12-crown-4 molecule. The water molecule hydrogen bonds a second 12-crown-4 unit. Both unique crown molecules and one of the nitrate anions are severely disordered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01041193
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The improved synthesis and crystal structure of 20-thiocrown-4 (1993)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 15 (1993), S. 145-152 
    Details
    ISSN: 1573-1111
    Keywords: 20-thiocrown-4 ; X-ray crystal structure ; crown ether
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract An improved synthesis of 20-thiocrown-4 is reported, which exploits the Kellogg method of cesium carbonate in DMF mediated macrocyclization of precondensed synthones which converge at the cycloicosane structure. The crystal structure of 20-thiocrown-4 reveals a rectangular conformation for the free ligand. Each sulfur is in onegauche and oneanti torsion angle. Four carbon positions make up the corners. There are two short sides comprised of −C−C− torsion angle sequencesg −ag− and two long sides (aaa, g −ag+). The S−C and C−C bond distances average 1.816(2) Å and 1.523(3) Å, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00710223
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...