Rotationally disordered phase of 1,3-dibromo-5-iodo-2,4,6-trimethylbenzene at 293 K.
作者： Soumia Ghanemi , Olivier Hernandez , Ali Boudjada , Jean Meinnel
DOI: 10.1107/S0108270109032715
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摘要: In the crystal state at room temperature, molecule of dibromoiodomesitylene (1,3-dibromo-5-iodo-2,4,6-trimethylbenzene), C9H9Br2I, is prone to strong disorder, apparently involving only three halogen sites (occupied identically by 66.7% Br and 33.3% I). This rotational type according previously published NMR measurements, corresponds fast 2π/3 stochastic in-plane reorientations whole between discernable locations. kind disorder can be revealed for first time diffractometry thanks C2v idealized molecular symmetry title compound, although it has been indirectly suspected temperature in other trihalogenomesitylenes similar packing but D3h symmetry. The average endocyclic angles facing Br/I methyl groups are 124.14 (6) 115.85 (2)°, respectively. angle normal aromatic ring (100) plane 4.1°. TLS analysis indicates that behave as a rigid body with respect thermal librations.
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sci-hub.se 参考文章(10)
J. Meinnel, M. Mani, A. Cousson, F. Boudjada, W. Paulus, M. Johnson, Structure of trihalogenomesitylenes and tunneling of the methyl groups protons II. Protonated tribromomesitylene principles and practice of constraint programming. ,vol. 261, pp. 165- 187 ,(2000) , 10.1016/S0301-0104(00)00242-1
Angela Altomare, Maria Cristina Burla, Mercedes Camalli, Giovanni Luca Cascarano, Carmelo Giacovazzo, Antonietta Guagliardi, Anna Grazia Giuseppina Moliterni, Giampiero Polidori, Riccardo Spagna, SIR97: a new tool for crystal structure determination and refinement Journal of Applied Crystallography. ,vol. 32, pp. 115- 119 ,(1999) , 10.1107/S0021889898007717
M. Plazanet, M.R. Johnson, A. Cousson, J. Meinnel, H.P. Trommsdorff, Molecular deformations of halogeno-mesitylenes in the crystal: structure, methyl group rotational tunneling, and numerical modeling Chemical Physics. ,vol. 285, pp. 299- 308 ,(2002) , 10.1016/S0301-0104(02)00817-0
P. Le Maguères, S. V. Lindeman, J. K. Kochi, Electron Redistribution of Aromatic Ligands in (Arene)Cr(CO)3 Complexes. Structural (Bond-Length) Changes as Quantitative Measures Organometallics. ,vol. 20, pp. 115- 125 ,(2001) , 10.1021/OM000658L
A. Boudjada, J. J. Meinnel, A. Boucekkine, O. J. Hernandez, M. T. Fernández-Diaz, Molecular conformation and methyl proton delocalization in triiodomesitylene: A combined density functional theory and single-crystal neutron diffraction study Journal of Chemical Physics. ,vol. 117, pp. 10173- 10183 ,(2002) , 10.1063/1.1519535
O. Hernandez, K.S. Knight, W. Van Beek, A. Boucekkine, A. Boudjada, W. Paulus, J. Meinnel, Phases II and IV of 1,3,5-trichloro-2,4,6-trimethylbenzene: Ab initio crystal structure determination by high‐resolution powder diffraction Journal of Molecular Structure. ,vol. 791, pp. 41- 52 ,(2006) , 10.1016/J.MOLSTRUC.2006.01.014
C. Malla Reddy, Michael T. Kirchner, Ravi C. Gundakaram, K. Anantha Padmanabhan, Gautam R. Desiraju, Isostructurality, Polymorphism and Mechanical Properties of Some Hexahalogenated Benzenes: The Nature of Halogen⋅⋅⋅Halogen Interactions Chemistry: A European Journal. ,vol. 12, pp. 2222- 2234 ,(2006) , 10.1002/CHEM.200500983
Paul W. Betteridge, J. Robert Carruthers, Richard I. Cooper, Keith Prout, David J. Watkin, CRYSTALS version 12: software for guided crystal structure analysis Journal of Applied Crystallography. ,vol. 36, pp. 1487- 1487 ,(2003) , 10.1107/S0021889803021800
Albert J. M. Duisenberg, Loes M. J. Kroon-Batenburg, Antoine M. M. Schreurs, An intensity evaluation method: EVAL-14 Journal of Applied Crystallography. ,vol. 36, pp. 220- 229 ,(2003) , 10.1107/S0021889802022628
Walter C. Hamilton, James W. Edmonds, Armin Tippe, Methyl group rotation and the low temperature transition in hexamethylbenzene. A neutron diffraction study Discussions of the Faraday Society. ,vol. 48, pp. 192- 204 ,(1969) , 10.1039/DF9694800192