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1.
Alan K. Brisdon Abeer M. T. Muneer Robin G. Pritchard 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(10):900-902
Halogen bonding is an intermolecular interaction capable of being used to direct extended structures. Typical halogen‐bonding systems involve a noncovalent interaction between a Lewis base, such as an amine, as an acceptor and a halogen atom of a halofluorocarbon as a donor. Vapour‐phase diffusion of 1,4‐diazabicyclo[2.2.2]octane (DABCO) with 1,2‐dibromotetrafluoroethane results in crystals of the 1:1 adduct, C2Br2F4·C6H12N2, which crystallizes as an infinite one‐dimensional polymeric structure linked by intermolecular N...Br halogen bonds [2.829 (3) Å], which are 0.57 Å shorter than the sum of the van der Waals radii. 相似文献
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A convenient and efficient method for the preparation of unsymmetrical and symmetrical diacetylenic ketones bearing a carboxylate group. 相似文献
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Farhad Haghjoo Nick Barnes Robin Pritchard 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(7):o219-o221
In the crystal structure of the title compound, 2C22H24P+·I82−, the I82− anion is located on a crystallographic inversion centre and consists of two tri‐iodide anions linked by di‐iodine at angles of 89.92 (4)° to form a planar `Z'‐shaped dianion. The octaiodides are linked via long‐range interactions [3.877 (11) Å] into infinite polyiodide ribbons. This is the first example of a structure containing an [(o‐tolyl)3PMe]+ cation, and the CMe—P—C—CMe torsion angles of −54.0 (11), −51.3 (11) and −48.2 (11)° indicate that the configuration is exo3. 相似文献
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Huw O. Pritchard 《Central European Journal of Chemistry》2011,9(5):753-760
The numerical simulation of the internal motions of a molecule undergoing a unimolecular reaction on an assumed potential
energy surface requires the step-by-step solution of a set of simultaneous differential equations. After several thousand
time steps, due to differences in the handling of rounding errors in different computing systems, the situation often arises
that no two computing machines will give the same result for a given trajectory, even when running the identical algorithm. 相似文献
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The Direct Synthesis of Hydrogen Peroxide Using Platinum‐Promoted Gold–Palladium Catalysts 下载免费PDF全文
Dr. Jennifer K. Edwards James Pritchard Li Lu Marco Piccinini Greg Shaw Dr. Albert F. Carley David J. Morgan Prof. Christopher J. Kiely Prof. Graham J. Hutchings 《Angewandte Chemie (International ed. in English)》2014,53(9):2381-2384
The direct synthesis of hydrogen peroxide offers a potentially green route to the production of this important commodity chemical. Early studies showed that Pd is a suitable catalyst, but recent work indicated that the addition of Au enhances the activity and selectivity significantly. The addition of a third metal using impregnation as a facile preparation method was thus investigated. The addition of a small amount of Pt to a CeO2‐supported AuPd (weight ratio of 1:1) catalyst significantly enhanced the activity in the direct synthesis of H2O2 and decreased the non‐desired over‐hydrogenation and decomposition reactions. The addition of Pt to the AuPd nanoparticles influenced the surface composition, thus leading to the marked effects that were observed on the catalytic formation of hydrogen peroxide. In addition, an experimental approach that can help to identify the optimal nominal ternary alloy compositions for this reaction is demonstrated. 相似文献