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861.
Palladium-catalyzed allylic alkylation of sulfenate anions, generated from beta-sulfinylesters by retro-Michael reaction, can take place under biphasic conditions. This new reaction provides a simple, mild, and efficient route to allyl sulfoxides in good yields. 相似文献
862.
Jean‐Daniel Compain Pierre Mialane Prof. Anne Dolbecq Dr. Israël Martyr Mbomekallé Dr. Jérôme Marrot Dr. Francis Sécheresse Prof. Eric Rivière Dr. Guillaume Rogez Dr. Wolfgang Wernsdorfer Dr. 《Angewandte Chemie (International ed. in English)》2009,48(17):3077-3081
Iron sandwich on a tungstate bun : Two new polyoxotungstates with paramagnetic iron(III) heteroatoms (see structure, W blue, Fe yellow, O red) possess S=15/2 and S=5 ground states. Both compounds are single‐molecule magnets, and the hexairon species shows large hysteresis (see picture) and quantum tunneling effects at low temperature. Electrochemical studies indicate that these species are stable in solution for a wide range of pH values.
863.
Guillaume Lafitte Kana Kunihiro Céline Bonneaud Bénédicte Dréan Frédéric Gaigne Véronique Parnet Romain Pierre Catherine Raffin Rodolphe Vatinel Jean-François Fournier Branislav Musicki Gilles Ouvry Claire Bouix-Peter Loic Tomas Craig S. Harris 《Tetrahedron letters》2017,58(39):3757-3759
The preparation of the boroxole motif traditionally relies on a 3-step process and the use of n-butyl lithium that can limit substrate scope. Herein during our exploration toward novel RORγ inhibitors, we identified a convenient one-pot preparation of the motif in good yields with good substrate scope. 相似文献
864.
Today, seeking new materials for tailor-made applications and new devices leads to explore the potential offered by various kinds of functional building blocks. Hence, it concerns not only solid-state chemists, physicists or materials engineers, but also the area of (supra)molecular chemistry, and biochemistry as well. This is especially clear in the field of hybrid multifunctional materials. Indeed, their design requires investigating new concepts derived from principles developed in these different disciplines. The aim of this critical review is to present the last achievements concerning transition metal hydroxide hybrids, their synthesis, flexibility and functional properties. They often provide nice model systems for understanding the correlation between structure and physical properties brought by the molecular moieties grafted onto the metal hydroxide basis layers. The contribution of the atomic scale modelling to the electronic structure calculations and structural optimization is also reported (216 references). 相似文献
865.
Bruno Bujoli Hlne Roussire Gilles Montavon Samia Laïb Pascal Janvier Bruno Alonso Franck Fayon Marc Petit Dominique Massiot Jean-Michel Bouler Jrme Guicheux Olivier Gauthier Sarah M. Lane Guillaume Nonglaton Muriel Pipelier Jean Lger Daniel R. Talham Charles Tellier 《Progress in Solid State Chemistry》2006,34(2-4):257
A new process for preparing oligonucleotide arrays is described that uses surface grafting chemistry which is fundamentally different from the electrostatic adsorption and organic covalent binding methods normally employed. Solid supports are modified with a mixed organic/inorganic zirconium phosphonate monolayer film providing a stable, well-defined interface. Oligonucleotide probes terminated with phosphate are spotted directly to the zirconated surface forming a covalent linkage. Specific binding of terminal phosphate groups with minimal binding of the internal phosphate diesters has been demonstrated. On the other hand, the reaction of a bisphosphonate bone resorption inhibitor (Zoledronate) with calcium deficient apatites (CDAs) was studied as a potential route to local drug delivery systems active against bone resorption disorders. A simple mathematical model of the Zoledronate/CDA interaction was designed that correctly described the adsorption of Zoledronate onto CDAs. The resulting Zoledronate-loaded materials were found to release the drug in different phosphate-containing media, with a satisfactory agreement between experimental data and the values predicted from the model. 相似文献
866.
Agnideep Das Jules Schleinitz Lydia Karmazin Bruno Vincent Dr. Nolwenn Le Breton Guillaume Rogez Dr. Aurélie Guenet Prof. Sylvie Choua Dr. Laurence Grimaud Prof. Marine Desage-El Murr 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(35):e202200596
Mechanisms combining organic radicals and metallic intermediates hold strong potential in homogeneous catalysis. Such activation modes require careful optimization of two interconnected processes: one for the generation of radicals and one for their productive integration towards the final product. We report that a bioinspired polymetallic nickel complex can combine ligand- and metal-centered reactivities to perform fast hydrosilylation of alkenes under mild conditions through an unusual dual radical- and metal-based mechanism. This earth-abundant polymetallic complex incorporating a catechol-alloxazine motif as redox-active ligand operates at low catalyst loading (0.25 mol%) and generates silyl radicals and a nickel-hydride intermediate through a hydrogen atom transfer (HAT) step. Evidence of an isomerization sequence enabling terminal hydrosilylation of internal alkenes points towards the involvement of the nickel-hydride species in chain walking. This single catalyst promotes a hybrid pathway by combining synergistically ligand and metal participation in both inner- and outer- sphere processes. 相似文献
867.
Dr. Johanne Ling Dr. Antoine Bruneau-Voisine Dr. Guillaume Journot Prof. Gwilherm Evano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(44):e202201356
A general copper-catalyzed carbonylative cross-coupling between amines and alkyl iodides is reported. Using a simple combination of catalytic amounts of copper(I) chloride and N,N,N’,N”,N”-pentamethyldiethylenetriamine in the presence of sodium hydroxide under carbon monoxide pressure, a broad range of alkyl iodides and amines can be efficiently coupled to the corresponding amides that are obtained in good to excellent yields. Notable features of this process – the first one relying on a base metal catalyst – include the availability and low cost of the catalytic system, its successful use with primary, secondary, tertiary alkyl iodides and all classes of amines – with no or limited competing nucleophilic substitution without CO incorporation – as well as its efficiency with complex alkyl iodides and amines. Mechanistic studies demonstrated that a radical pathway is operative and the key role of CO. 相似文献
868.
Martin Gillard Guillaume Piraux Martin Daenen Michaël Abraham Dr. Ludovic Troian-Gautier Dr. Laure Bar Hugues Bonnet Prof. Frédérique Loiseau Dr. Hélène Jamet Dr. Jérôme Dejeu Prof. Eric Defrancq Prof. Benjamin Elias 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(66):e202202251
Photosensitizers that gather high photo-oxidizing power and strong visible-light absorption are of great interest in the development of new photo-chemotherapeutics. Indeed, such compounds constitute attractive candidates for the design of type I photosensitizers that are not dependent on the presence of oxygen. In this paper, we report on the synthesis and studies of new ruthenium(II) complexes that display strong visible-light absorption and can oxidize guanine residues under visible-light irradiation, as evidenced by nanosecond transient absorption spectroscopy. The reported compounds also tightly bind to G-quadruplex DNA structures from the human telomeric sequence (TTAGGG repeat). The kinetic and thermodynamic parameters of the interaction of these Ru(II) complexes with G-quadruplex and duplex DNA were studied thanks to luminescence titrations and bio-layer interferometry measurements, which revealed higher affinities towards the non-canonical G-quadruplex architecture. Docking experiments and non-covalent ionic analysis allowed us to gain information on the mode and the strength of the interaction of the compounds towards G-quadruplex and duplex DNA. The different studies emphasize the substantial influence of the position and the number of non-chelating nitrogen atoms on the interaction with both types of DNA secondary structures. 相似文献
869.
Arnaud de Zordo-Banliat Dr. Kevin Grollier Jordan Vigier Dr. Erwann Jeanneau Dr. Guillaume Dagousset Dr. Bruce Pegot Dr. Emmanuel Magnier Dr. Thierry Billard 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(63):e202202299
Trifluorometylselenolation via C−H activation is barely described in literature. In particular, no such vinylic functionalization has been yet described. Herein, a palladium-catalyzed trifluoromethylselenolation of vinylic C−H bonds is described. The 5-methoxy-8-aminoquinoline has been used as auxiliary directing group to perform this reaction. The reaction gives excellent yields with α-substituted compounds whatever the substituents and a microwave activation can be used to accelerate the reaction. With β-substituted substrates lower yields, but still satisfactory, are obtained. This methodology was also successfully extended to other fluoroalkylselenyl groups. 相似文献
870.
Guillaume James 《Archive for Rational Mechanics and Analysis》2001,160(1):41-90
We consider internal travelling waves in a perfect stratified fluid, in the singular limit case when smooth stratifications approach a discontinuous two-layer profile. Our analysis concerns two-dimensional waves of small amplitude, propagating in an infinite horizontal strip of finite depth. The problems with smooth or discontinuous stratification are formulated as a unifying spatial evolution problem, where the stratification ρ plays the role of a functional parameter. The vector field is not smooth with respect to ρ, but has some weak continuity. When the Froude number is close to a critical value, we reduce the problem to one on a center manifold in a neighborhood of the trivial state independent of ρ (for the usual topology). Considering a weaker topology, we prove the continuity in ρ of the center manifold. Then the small solutions are described by an ordinary differential equation in ?2, which depends continuously on ρ in the C k norm. 相似文献