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51.
Zhang P Jacques PA Chavarot-Kerlidou M Wang M Sun L Fontecave M Artero V 《Inorganic chemistry》2012,51(4):2115-2120
The combination of cobalt diimine-dioxime complexes with a cyclometalated iridium photosensitizer gives efficient systems for hydrogen generation under visible-light irradiation using triethylamine as a sacrificial electron donor. Interestingly, the addition of triphenylphosphine (PPh(3)) to the medium results in a significant improvement of the stability of the system, with up to ~700 turnovers achieved within 10 h. UV-visible spectroscopic monitoring of the reaction allows identification of a PPh(3)-coordinated Co(I) intermediate as the active species. Mechanistic issues regarding (i) the photogeneration of the Co(I) species, (ii) the nature of the active species, and (iii) the influence of PPh(3) on the H(2)-evolution mechanism are discussed. 相似文献
52.
Yan Suffren Isabelle Gautier‐Luneau Celine Darie Celine Goujon Murielle Legendre Olivier Leynaud 《ChemInform》2013,44(49):no-no
A new phase of silver iodate, β‐AgIO3, is obtained by heating α‐AgIO3 at 2.7 GPa at <240 °C for 30 min. 相似文献
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Prof. Dr. Christophe Copéret Florian Allouche Ka Wing Chan Prof. Matthew P. Conley Murielle F. Delley Dr. Alexey Fedorov Ilia B. Moroz Dr. Victor Mougel Margherita Pucino Dr. Keith Searles Dr. Keishi Yamamoto Dr. Pavel A. Zhizhko 《Angewandte Chemie (International ed. in English)》2018,57(22):6398-6440
Many industrial catalysts contain isolated metal sites on the surface of oxide supports. Although such catalysts have been used in a broad range of processes for more than 40 years, there is often a very limited understanding about the structure of the catalytically active sites. This Review discusses how surface organometallic chemistry (SOMC) engineers surface sites with well‐defined structures and provides insight into the nature of the active sites of industrial catalysts; the Review focuses in particular on olefin production and conversion processes. 相似文献
54.
Brigitte Bouteau Jean-Charles Lancelot Max Robba 《Journal of heterocyclic chemistry》1990,27(6):1649-1651
The synthesis of 1,2,4-triazolo[4,3-a] and [2,3-a]pyridines 7, 8 was achieved by cyclization of 2-hydrazino-8-nitropyridine 3a with formic acid. The 4,5,6,7-tetrahydro-1,2,4-triazolo[2,3-a]pyridine 13 and 8-amino-1,2,4-triazolo[2,3-a]pyridine 9 were obtained by catalytic hydrogenation. The reduction of triazolo pyridine 8 using stannous chloride led to the intermediate compound 10 which with acetic anhydride afforded 8-acetylamino-5-chloro-1,2,4-triazolo[2,3-a]pyridine 10a . The structure of the derivatives was determined by 1H-nmr (DMSO-d6). 相似文献
55.
Hamelin O Ménage S Charnay F Chavarot M Pierre JL Pécaut J Fontecave M 《Inorganic chemistry》2008,47(14):6413-6420
Bis(diimine)-ruthenium complexes constitute a class of catalysts with good activity for oxidation reactions, such as sulfoxidation and epoxidation. The synthesis and the full characterization of a new ruthenium complex bearing an original pentadentate ligand (L5pyr for 2,6-bis-(6-ethyl-2,2'-bipyridyl)-pyridine) is reported. Comparison of its activity with regard to[Ru(bpy)2(CH3CN)2](2+) and [Ru(bpy)2(py)(CH3CN)](2+) during alkene and sulfide oxidation allowed us to conclude that the addition of a fifth pyridine ligand in the coordination sphere improves the efficiency of the catalyst. Moreover, under these oxidation conditions a hydroxylation of the ligand L5pyr led to a better activity than its analogue [Ru(bpy)2(py)(CH3CN)](2+), especially during epoxidation of alkenes by PhI(OAc)2. 相似文献
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57.
Murielle Na?tali Jean-Marie Herry Eugen Hnatiuc Georges Kamgang Jean-Louis Brisset 《Plasma Chemistry and Plasma Processing》2012,32(4):675-692
The mechanism of bacterial inactivation by electric discharges (non-thermal plasma) is examined on the basis of the action of the formed peroxynitrite and hydrogen peroxide on the external membrane of bacteria. A model accounts for the gas to liquid transfer of the active species which react with the bacterial wall at the liquid surface or /and in the bulk solution. Direct exposure to the glidarc discharge induces a pseudo zero order decay of the bacterial concentration, followed by a pseudo 1st order step for low concentrations. Post-discharge reactions develop after switching off the discharge according to a 1st order mechanism and show that active species drift in the solution. Additionally the bactericidal properties of pure water exposed to the discharge (i.e., ??Plasma Activated Water??) was evidenced even 24?h after performing the plasma treatment. 相似文献
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59.
Microsecond X‐ray Absorption Spectroscopy Identification of CoI Intermediates in Cobaloxime‐Catalyzed Hydrogen Evolution
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Dr. Grigory Smolentsev Bianca Cecconi Alexander Guda Dr. Murielle Chavarot‐Kerlidou Prof. Jeroen A. van Bokhoven Dr. Maarten Nachtegaal Dr. Vincent Artero 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(43):15158-15162
Rational development of efficient photocatalytic systems for hydrogen production requires understanding the catalytic mechanism and detailed information about the structure of intermediates in the catalytic cycle. We demonstrate how time‐resolved X‐ray absorption spectroscopy in the microsecond time range can be used to identify such intermediates and to determine their local geometric structure. This method was used to obtain the solution structure of the CoI intermediate of cobaloxime, which is a non‐noble metal catalyst for solar hydrogen production from water. Distances between cobalt and the nearest ligands including two solvent molecules and displacement of the cobalt atom out of plane formed by the planar ligands have been determined. Combining in situ X‐ray absorption and UV/Vis data, we demonstrate how slight modification of the catalyst structure can lead to the formation of a catalytically inactive CoI state under similar conditions. Possible deactivation mechanisms are discussed. 相似文献
60.
The synthesis of new organophosphorus compounds containing a carbamoyl unit is performed by nucleophilic addition or cycloaddilion on substituted acetylisocyanates. 相似文献