The unusual title macrocyclic structure, C60H54B2O4, has been isolated from exposure of 3-BF(3)-1-phenylbuta-1,3-diene to both air and moisture in an attempt to obtain crystals of the starting butadiene compound. Formation of the macrocycle from six molecules of the starting butadiene material is rationalized and its structural features are compared with those of other B(OR)2-substituted cyclohexane and benzene ring containing structures. Molecules reside on crystallographic centers of inversion and there are no intermolecular interactions of note in the crystal structure.
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http://dx.doi.org/10.1107/S0108270107050986 | DOI Listing |
Macromol Rapid Commun
January 2025
School of Polymer Science and Engineering, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
As the demand for clean water intensifies, developing effective methods for removing pollutants from contaminated sources becomes increasingly crucial. This work establishes a method for additive manufacturing of functional polymer sorbents with hollow porous features, designed to enhance interactions with organic micropollutants. Specifically, core-shell filaments are used as the starting materials, which contain polypropylene (PP) as the shell and poly(acrylonitrile-co-butadiene-co-styrene) as the core, to fabricate 3-dimensional (3D) structures on-demand via material extrusion.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95447 Bayreuth, Germany.
Rubbers prepared from technical poly(butadiene) and natural poly(isoprene) are studied by field-cycling (FC) H NMR relaxometry to elucidate the changes of the relaxation spectrum. Starting with the non-cross-linked polymer successively cross-links are introduced via sulfur or peroxide vulcanization. Applying an advanced home-built relaxometer allows one to probe entanglement dynamics in addition to Rouse dynamics.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Key Laboratory of Organosilicon Material Technology of Zhejiang Province, College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou, 311121, P. R. China.
In industry, the two important nitrile starting materials, adiponitrile and 2-methylglutaronitrile, are primarily manufactured through the well-known DuPont process, which consists of a tandem sequence including first hydrocyanation, isomerization and second hydrocyanation. However, this mature process has the intrinsic defects of step efficiency and regioselectivity. Herein, we report a nickel-catalyzed divergent, one-step double hydrocyanation of 1,3-butadiene to produce either adiponitrile or 2-methylglutaronitrile in high regioselectivity.
View Article and Find Full Text PDFMolecules
October 2024
Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Hong Kong 999077, China.
The propagation rate coefficient () is one of the most crucial kinetic parameters in free-radical polymerization (FRP) as it directly governs the rate of polymerization and the resulting molecular weight distribution. The in FRP can typically be obtained through experimental measurements or quantum chemical calculations, both of which can be time consuming and resource intensive. Herein, we developed a machine learning model based solely on the structural features of monomers involved in FRP, utilizing molecular embedding and a Lasso regression algorithm to predict more efficiently and accurately.
View Article and Find Full Text PDFMolecules
March 2024
Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1-E4-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
The carboxylation of unsaturated amine and alcohol compounds, including 4-benzylamino-1-phenyl-1-butyne (homopropargylamine), 2-butyne-1-ol (propargylic alcohol), and 2,3-butadiene-1-ol (allenylmethyl alcohol), using the hydroxidogold(I) complex, AuOH(IPr) [IPr = 1,3-bis(2,6-diisopropylphenyl)-imidazol-2-ylidene], produces corresponding alkenylgold(I) complexes with a cyclic urethane or carbonate framework in high yields. The reaction takes place in aprotic THF at room temperature under the atmospheric pressure of CO in the absence of base additives. The products were characterized by NMR spectroscopy, elemental analysis, and X-ray crystallography.
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