A new family of diphenylethanes has been synthesized as conformationally restricted analogues of antimitotic combretastatins. The two phenyl rings are linked between the para-phenolic positions through a 3-oxapentamethylene or hexamethylene chain. The key macrocyclization step was achieved in moderate yields by using an intramolecular McMurry pinacol coupling of linked aromatic dialdehydes, except for the nitro-substituted compounds. The relative stereochemistry of the isomeric pinacols was determined by a combination of spectroscopic, chemical derivatization, and molecular-modeling approaches. The NMR spectra of these compounds (with a polyoxygenated crownophane skeleton) indicate severe conformational restrictions relative to their parent combretastatins; the rotation of the phenyl rings is hampered by interactions of their substituents and the linker and the conformational restrictions imposed by the substituted bridge.
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http://dx.doi.org/10.1002/chem.200700323 | DOI Listing |
J Chem Phys
January 2025
Department of Chemistry, University of Houston, Houston, Texas 77204, USA.
Rubrene is one of the leading organic semiconductors in scientific and industrial research, showing good conductivities and utilities in devices such as organic field-effect transistors. In these applications, the rubrene crystals often contact ionic liquids and other materials. Consequently, their surface properties and interfacial interactions influence the device's performance.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
October 2024
Department of PG Studies and Research in Physics Albert Einstein Block UCS Tumkur University, Tumkur Karnataka-572103 India.
In the title compound, CHNO, the torsion angle associated with the phenyl benzoate group is -173.7 (2)° and that for the benz-yloxy group is -174.8 (2)° establishing an -type conformation.
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October 2024
Department of Organic Chemistry University of Madras, Guindy Campus Chennai-600 025 Tamilnadu India.
Two new phenyl-sulfonyl-indole derivatives, namely, -{[3-bromo-1-(phenyl-sulfon-yl)-1-indol-2-yl]meth-yl}--(4-bromo-3-meth-oxy-phen-yl)benzene-sulfonamide, CHBrNOS, (), and ,-bis-{[3-bromo-1-(phenyl-sulfon-yl)-1-indol-2-yl]meth-yl}benzene-sulfonamide, CHBrNOS, (), reveal the impact of intra-molecular π-π inter-actions of the indole moieties as a factor not only governing the conformation of ,-bis-(1-indol-2-yl)meth-yl)amines, but also significantly influencing the crystal patterns. For , the crystal packing is dominated by C-H⋯π and π-π bonding, with a particular significance of mutual indole-indole inter-actions. In the case of , the mol-ecules adopt short intra-molecular π-π inter-actions between two nearly parallel indole ring systems [with the centroids of their pyrrole rings separated by 3.
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October 2024
In the title mol-ecule, CHClNO, the 2-chloro-phenyl group is disordered to a small extent [occupancies 0.875 (2)/0.125 (2)].
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October 2024
Institut für Organische Chemie Technische Universität Bergakademie, Freiberg, Leipziger Str 29 09599 Freiberg/Sachsen Germany.
Crystal growth of 2-(3,4,5-triphen-ylphen-yl)acetic acid () from aceto-nitrile yields a monosolvate, CHO·CHCN, of the space group 1. In the crystal, the title mol-ecule adopts a conformation in which the three phenyl rings are arranged in a paddlewheel-like fashion around the central arene ring and the carboxyl residue is oriented nearly perpendicular to the plane of this benzene ring. Inversion-symmetric dimers of O-H⋯O-bonded mol-ecules of represent the basic supra-molecular entities of the crystal structure.
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