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941.
Xian Tao Ke‐Cheng Shen Qing‐Yun Tang Meng Feng Jiang‐Tao Fang Yu‐Long Wang Ying‐Zhong Shen 《应用有机金属化学》2012,26(2):67-73
Six organophosphine/phosphite‐stabilized silver(I) N‐hydroxysuccinimide complexes of type [C4H4NO3Ag?Ln] (L = PPh3; n = 1, 2a; n = 2, 2b; L = P(OEt)3; n = 1, 2c; n = 2, 2 d; L = P(OMe)3; n = 1, 2e; n = 2, 2f) were prepared. These complexes were obtained in high yields and characterized by elemental analysis, 1H NMR, 13 C{1H} NMR and IR spectroscopy, respectively. The molecular structure of 2b has been determined by X‐ray single‐crystal analysis in which the silver atom is in a distorted tetrahedral geometry. An interstitial methanol solvent molecule is hydrogen bonded to the oxygen atom of N‐hydroxysuccinimide molecule. Complex 2f was used to deposit silver films by metal‐organic chemical vapor deposition (MOCVD) for the first time. The silver film obtained at 480 °C is dense and homogeneous, which is composed of many well‐isolated, granular particulates spreading all over the substrate surface. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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943.
Reactivity of [Ge9{Si(SiMe3)3}3]− Towards Transition‐Metal M2+ Cations: Coordination and Redox Chemistry
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Dr. Oleksandr Kysliak Dr. Claudio Schrenk Prof. Dr. Andreas Schnepf 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18787-18793
Recently the metalloid cluster compound [Ge9Hyp3]? ( 1 ; Hyp=Si(SiMe3)3) was oxidatively coupled by an iron(II) salt to give the largest metalloid Group 14 cluster [Ge18Hyp6]. Such redox chemistry is also possible with different transition metal (TM) salts TM2+ (TM=Fe, Co, Ni) to give the TM+ complexes [Fe(dppe)2][Ge9Hyp3] ( 3 ; dppe=1,2‐bis(diphenylphosphino)ethane), [Co(dppe)2][Ge9Hyp3] ( 4 ), [Ni(dppe)(Ge9Hyp3)] ( 5 ) and [Ni(dppe)2(Ge9Hyp3)]+ ( 6 ). Such a redox reaction does not proceed for Mn, for which a salt metathesis gives the first open shell [Hyp3Ge9‐M‐Ge9Hyp3] cluster ( 2 ; M=Mn). The bonding of the transition metal atom to 1 is also possible for Ni (e.g., compound 6 ), in which one or even two nickel atoms can bind to 1 . In contrast to this in case of the Fe and Co compounds 3 and 4 , respectively, the transition‐metal atom is not bound to the Ge9 core of 1 . The synthesis and the experimentally determined structures of 2 – 6 are presented. Additionally the bonding within 2 – 6 is analyzed and discussed with the aid of EPR measurements and quantum chemical calculations. 相似文献
944.
L. V. Constantino E. T. Lopes E. C. Frachini A. M. Monteiro M. J. Santos 《Surface and interface analysis : SIA》2017,49(12):1206-1213
Herein is reported the application of models on sorption isotherms for removal of silver ions from aqueous solution using 2 bentonites: SWy‐2 and BaVC‐1, low‐cost sorbents. Physicochemical attributes were determined for both materials, and sorption experiments were carried out in batch system. The pH before and after sorption decreased from 7.8 to 6.1 and 8.4 to 6.7 for SWy‐2 and BaVC‐1, respectively. Langmuir, Freundlich, Sips, Toth, Kolbe‐Corrigan, Khan, and Radke‐Prausnitiz models were applied to the data. The models showed good fit with R2 above 0.999 and RMSE < 2%. The adjustable parameters indicated high affinity of silver ions to BaVC‐1 sorption sites, demonstrating high sorption capacity and thermodynamic feasibility. In general, SWy‐2 showed most heterogeneous sorption sites, while BaVC‐1 showed most homogeneous sites. Moreover, BaVC‐1 has shown larger surface area and smaller particle size, which can explain its better sorption performance as compared with SWy‐2. 相似文献
945.
《应用有机金属化学》2017,31(10)
This work reports the preparation of multiwalled carbon nanotube/pramipexole/Ag (CNT/pra/Ag) as a novel antibacterial agent, in which pramipexole groups are utilized as linkers to secure Ag nanoparticles to carbon nanotube surfaces without agglomeration. The resulting CNT/pra/Ag sample was characterized by performing transmission and scanning electron microscopy, wavelength‐ and energy‐dispersive X‐ray, X‐ray diffraction, Fourier transform infrared, inductively coupled plasma and Raman measurements. Using this approach, monodisperse spherical Ag nanoparticles in CNT/pra/Ag have narrow size distributions with average diameters of ca 3–8 nm. The antibacterial activity of CNT/pra/Ag was investigated against bacterial species Staphylococcus aureus , methicillin‐resistant S. aureus , Pseudomonas aeruginosa and Escherichia coli using the paper‐disc diffusion method and by determining the minimal inhibitory concentration. CNT/pra/Ag showed better inhibitory activity towards Gram‐positive bacteria than Gram‐negative bacteria in this study, which indicates its potential as an antibacterial material for laboratory and medical purposes. 相似文献
946.
Oxidation of nitrogen-containing heteroaryl-2-methanols to esters with Ag2O and isopropyl iodide is reported. This methodology is very mild and can tolerate many functional groups. 相似文献
947.
An Atomically Precise Alkynyl‐Protected PtAg42 Superatom Nanocluster and Its Structural Implications
《化学:亚洲杂志》2017,12(22):2904-2907
The synthesis and structure determination of an alkynyl‐protected Pt‐doped Ag superatom nanocluster, [PtAg42(C≡CC6H4CH3)28](SbF6)6 (1) , are reported. The metallic core of this cluster can be viewed as a concentric three‐shell Russian doll comprising Pt@Ag12@Ag30, in which the missing icosidodecahedral Ag30 shell and a new structural unit, M43, have been observed. On the surface of 1 , 28 alkynyl groups and 4 SbF6− anions were found co‐protecting it. The protective role of SbF6− in nanoclusters is unprecedented. Moreover, of the 28 alkynyl ligands, 12 are connected not only with the outermost Ag30 shell, but also the inner Ag12 shell through the twelve pentagonal faces of the outermost icosidodecahedral Ag30 shell. Overall, by determining the crystal structure of 1 , we discovered the missing icosidodecahedral Ag30 shell and the protective effect of SbF6− anions and demonstrated a novel M43 structural unit and the unique penetrability of pentagonal faces. 相似文献
948.
《应用有机金属化学》2017,31(1)
A general and efficient synthesis of trifluoromethyl‐substituted 5‐alkylidene‐1,3‐dioxolanes using AgNO3 and DBU cooperatively catalyzed domino reaction of propargylic alcohols and trifluoromethyl ketones is described. The reaction tolerates a broad range of functional groups, and the desired products are obtained in good to excellent yields (62–99%) with acceptable diastereoselectivities. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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