排序方式: 共有65条查询结果,搜索用时 15 毫秒
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Meiling Guo Prof. Dr. Zhaochi Feng Dr. Guanna Li Dr. Jan P. Hofmann Dr. Evgeny A. Pidko Dr. Pieter C. M. M. Magusin Qiang Guo Prof. Dr. Bert M. Weckhuysen Prof. Dr. Emiel J. M. Hensen Dr. Fengtao Fan Prof. Dr. Can Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(38):12078-12084
The mechanism of crystallization of microporous titanosilicate ETS‐10 was investigated by Raman spectroscopy combined with 29Si magic‐angle spinning (MAS) NMR spectroscopy, DFT calculations, and SEM imaging. The formation of three‐membered ring species is shown to be the key step in the hydrothermal synthesis of ETS‐10. They are formed by means of a complex process that involves the interaction of silicate species in the reaction mixture, which promotes the dissolution of TiO2 particles. These insights into the mechanism of ETS‐10 growth led to the successful development of a new synthesis route to the vanadosilicate AM‐6 that involves the use of intermediates that contain three‐membered ring species as an initiator. 相似文献
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van der Vlugt JI Pidko EA Vogt D Lutz M Spek AL Meetsma A 《Inorganic chemistry》2008,47(11):4442-4444
The versatile coordination behavior of the PNP ligands 1A (2,6-bis[(di-tert-butylphosphino)methyl]pyridine) and 1B (2,6-bis[(diphenylphosphino)methyl]pyridine) to CuI is described, whereby a hemilabile interaction of the pyridine N-donor atom to the copper center resulted in a rare T-shaped complex with 1A, while with 1B also a tetracoordinated species could be isolated. Theoretical calculations support the weak interaction of the pyridine N donor in 1A with the Cu center. 相似文献
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Dr. Coen Hendriksen Dr. Evgeny A. Pidko Dr. Gang Yang Dr. Benjamin Schäffner Prof. Dr. Dieter Vogt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(38):12037-12040
With regard to sustainability, carbon dioxide (CO2) is an attractive C1 building block. However, due to thermodynamic restrictions, reactions incorporating CO2 are relatively limited so far. One of the so‐called “dream reactions” in this field is the catalytic oxidative coupling of CO2 and ethene and subsequent β‐H elimination to form acrylic acid. This reaction has been studied intensely for decades. However up to this date no suitable catalytic process has been established. Here we show that the catalytic conversion of ethene and CO2 to acrylate is possible in the presence of a homogeneous nickel catalyst in combination with a “hard” Lewis acid. For the first time, catalytic conversion of CO2 and ethene to acrylate with turnover numbers (TON) of up to 21 was demonstrated. 相似文献
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Ming Shi Guanna Li Jianming Li Xu Jin Xiaoping Tao Bin Zeng Prof. Evgeny A. Pidko Prof. Rengui Li Prof. Can Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(16):6652-6657
Surface atomic arrangement and coordination of photocatalysts highly exposed to different crystal facets significantly affect the photoreactivity. However, controversies on the true photoreactivity of a specific facet in heterogeneous photocatalysis still exits. Herein, we exemplified well-defined BiOBr nanosheets dominating with respective facets, (001) and (010), to track the reactivity of crystal facets for photocatalytic water splitting. The real photoreactivity of BiOBr-(001) were evidenced to be significantly higher than BiOBr-(010) for both hydrogen production and oxygen evolution reactions. Further in situ photochemical probing studies verified the distinct reactivity is not only owing to the highly exposed facets, but dominated by the co-exposing facets, leading to an efficient spatial separation of photogenerated charges and further making the oxidation and reduction reactions separately occur with different reaction rates, which ordains the fate of the true photoreactivity. 相似文献
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Iris de Krom Dr. Evgeny A. Pidko Dr. Martin Lutz Prof. Dr. Christian Müller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(23):7523-7531
RhIII and IrIII complexes based on the λ3‐P,N hybrid ligand 2‐(2′‐pyridyl)‐4,6‐diphenylphosphinine ( 1 ) react selectively at the P?C double bond to chiral coordination compounds of the type [( 1 H ? OH)Cp*MCl]Cl ( 2 , 3 ), which can be deprotonated with triethylamine to eliminate HCl. By using different bases, the pKa value of the P? OH group could be estimated. Whereas [( 1 H ? O)Cp*IrCl] ( 4 ) is formed quantitatively upon treatment with NEt3, the corresponding rhodium compound [( 1 H ? O)Cp*RhCl] ( 5 ) undergoes tautomerization upon formation of the λ5σ4‐phosphinine rhodium(III) complex [( 1? OH)Cp*RhCl] ( 6 ) as confirmed by single‐crystal X‐ray diffraction. Blocking the acidic P? OH functionality in 3 by introducing a P? OCH3 substituent leads directly to the λ5σ4‐phosphinine iridium(III) complex ( 8 ) upon elimination of HCl. These new transformations in the coordination environment of RhIII and IrIII provide an easy and general access to new transition‐metal complexes containing λ5σ4‐phosphinine ligands. 相似文献
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Ethane adsorption on the hydrogen, sodium, and zinc forms of faujasite brings about polarization anisotropy of the C-H stretching vibrations. This anisotropy shows itself most clearly as perturbation of the vibrational mode analogous to the breathing C-H mode ν1 of free ethane. The relative intensity and the low-frequency shift of the absorption band due to the distorted ν1 mode increase with increasing perturbation caused by the C2H6-adsorption site interaction. The polarizing power of adsorption sites increases in the order H+ < Na+ < Zn2+. The C-H stretching vibrations in ethane adsorbed on the cationic forms of the Y zeolite are not symmetry-forbidden; accordingly, adsorbed ethane gives more absorption bands than gaseous ethane. The interaction between ethane and zinc cations in the Y zeolite structure eliminates not only the symmetry forbiddenness but also the twofold degeneracy of the C-H stretches.__________Translated from Kinetika i Kataliz, Vol. 46, No. 3, 2005, pp. 434–440.Original Russian Text Copyright © 2005 by Pidko, Kazanskii. 相似文献