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  • S. Garai, H. Bögge, A. Merca, O. A. Petina, A. Grego, P. Gouzerh, E. T. K. Haupt, I. A. Weinstock, et A. Müller, « Densely Packed Hydrophobic Clustering: Encapsulated Valerates Form a High-Temperature-Stable {Mo132 } Capsule System », Angewandte Chemie (International Ed. in English), vol. 55, nᵒ 23, p. 6634-6637.
    Résumé : Porous molecular nanocontainers of {Mo132 }-type Keplerates offer unique opportunities to study a wide variety of relevant phenomena. An impressive example is provided by the highly reactive {Mo132 -CO3 } capsule, the reaction of which with valeric acid results in the very easy release of carbon dioxide and the uptake of 24 valerate ions/ligands that are integrated as a densely packed aggregate, thus indicating the unique possibility of hydrophobic clustering inside the cavity. Two-dimensional NMR techniques were used to demonstrate the presence of the 24 valerates and the stability of the capsule up to ca. 100 °C. Increasing the number of hydrophobic parts enhances the stability of the whole system. This situation also occurs in biological systems, such as globular proteins or protein pockets.
    Mots-clés : confinement effects, dense packing, E-POM, hydrophobic interactions, NMR spectroscopy, POLE 2, porous capsules.

  • D. Garnier, J. - R. Jiménez, Y. Li, J. von Bardeleben, Y. Journaux, T. Augenstein, E. M. B. Moos, M. T. Gamer, F. Breher, et R. Lescouëzec, « K⊂{[FeII(Tp)(CN)3]4[CoIII(pzTp)]3[CoII(pzTp)]}: a neutral soluble model complex of photomagnetic Prussian blue analogues », Chemical Science, vol. 7, nᵒ 8, p. 4825-4831, 2016.

  • A. Giustiniani, P. Guégan, M. Marchand, C. Poulard, et W. Drenckhan, « Generation of Silicone Poly-HIPEs with Controlled Pore Sizes via Reactive Emulsion Stabilization », Macromolecular Rapid Communications, vol. 37, nᵒ 18, p. 1527-1532, 2016.

  • J. - P. Goddard, C. Ollivier, et L. Fensterbank, « Photoredox Catalysis for the Generation of Carbon Centered Radicals », Accounts of Chemical Research, vol. 49, nᵒ 9, p. 1924-1936.
    Résumé : ConspectusRadical chemistry has witnessed over the last decades important advances that have positioned it as a methodology of choice in synthetic chemistry. A number of great attributes such as specific reactivities, the knowledge of the kinetics of most elementary processes, the functional group tolerance, and the possibility to operate cascade sequences are clearly responsible for this craze. Nevertheless, at the end of the last century, radical chemistry appeared plagued by several hurdles to overcome such as the use of environmentally problematic mediators or the impossibility of scale up. While the concept of photocatalysis was firmly established in the coordination chemistry community, its diffusion in organic synthetic chemistry remained sporadic for decades until the end of the 2000s with the breakthrough merging of organocatalysis and photocatalysis by the MacMillan group and contemporary reports by the groups of Yoon and Stephenson. Since then, photoredox catalysis has enjoyed particularly active and intense developments. It is now the topic of a still increasing number of publications featuring various applications from asymmetric synthesis, total synthesis of natural products, and polymerization to process (flow) chemistry.In this Account, we survey our own efforts in this domain, focusing on the elaboration of new photocatalytic pathways that could lead to the efficient generation of C-centered functionalized alkyl and aryl radicals. Both reductive and oxidative manifolds are accessible through photoredox catalysis, which has guided us along these lines in our projects.Thus, we studied the photocatalytic reduction of onium salts such as sulfoniums and iodoniums for the production of the elusive aryl radical intermediates. Progressing to more relevant chemistry for synthesis, we examined the cleavage of C–O and the C–Br bonds for the generation of alkyl C-centered radicals. Activated epoxides could serve as valuable substrates of a photocatalyzed variant of the Nugent–RajanBabu–Gansäuer homolytic cleavage of epoxides. Using imidazole based carbamates, we could also devise the first photocatalyzed Barton–McCombie deoxygenation reaction. Finally, bromophenylacetate can be reduced using the [Au2(μ-dppm)2]Cl2 photocatalyst under UVA or visible-light. This was used for the initiation of the controlled atom transfer radical polymerization of methacrylates and acrylates in solution or laminate.Our next endeavors concerned the photocatalyzed oxidation of stabilized carbanions such as enolates of 1,3-dicarbonyl substrates, trifluoroborates, and more extensively bis-catecholato silicates. Because of their low oxidation potentials, the later have proved to be exquisite sources of radical entities, which can be engaged in diverse intermolecular reactions such as vinylation, alkynylation, and conjugate additions. The bis-catecholato silicates were also shown to behave as excellent partners of dual photoredox–nickel catalysis leading in an expeditious manner to libraries of cross coupling products.
    Mots-clés : MACO, POLE 1.

  • L. Goujard, P. - J. Roumanet, B. Barea, Y. Raoul, F. Ziarelli, J. L. Petit, N. Jarroux, E. Ferré, et P. Guégan, « Evaluation of the Effect of Chemical or Enzymatic Synthesis Methods on Biodegradability of Polyesters », Journal of Polymers and the Environment, vol. 24, nᵒ 1, p. 64-71, mars 2016.
    Résumé : This work compares the biodegradability of polyesters produced by an esterification reaction between glycerol and oleic di-acid (D 18:1) issued from green chemical pathways, via either classical thermo-chemical methods, or an enzymatic method using the immobilized lipase of Candida antartica B (Novozym 435). An elastomeric polymer synthesized by enzymatic catalysis is more biodegradable than an elastomeric thermo-chemical polyester synthesized by a standard chemical procedure. This difference lies in percentage of the dendritic motifs, in values of the degree of substitution, and certainly in cross-links inducing an hyper-branched structure less accessible to the lipolytic enzymes in a waste treatment plant. However, when the elastomeric polymer synthesized by enzymatic catalysis is processed at high temperature as required for certain industrial applications, it presents an identical rate of biodegradation than the chemical polyester. The advantages of the thermo-chemical methods are greater speed and lower cost. Enzymatic synthesis appears be suited to producing polyesters, devoid of metallic catalysts, which must be used without processing at high temperature to keep a high biodegradability.
    Mots-clés : POLE 4, POLYMERES.

  • C. Grazon, J. Rieger, P. Beaunier, R. Méallet-Renault, et G. Clavier, « Fluorescent core–shell nanoparticles and nanocapsules using comb-like macromolecular RAFT agents: synthesis and functionalization thereof », Polymer Chemistry, vol. 7, nᵒ 25, p. 4272-4283.
    Résumé : Fluorescent nanoparticles and nanocapsules (FNPs) were synthesized via a one-pot RAFT miniemulsion process copolymerizing BODIPY-methacrylate and styrene in water. Ultra-bright sub-100 nm core–shell nanoparticles could be obtained with BODIPY covalently linked in the core, and possessing various shells. The nature and architecture of the particle shells could be tuned by using different macromolecular RAFT (macro-RAFT) agents in the miniemulsion polymerization process. The macro-RAFT agents were composed of poly(ethylene oxide) acrylate (PEOA) and/or acrylic acid (AA), owing to their biocompatibility and functionality respectively, in different proportions. Interestingly, with comb-like macro-RAFT agents comprising a high number of PEOA, nanocapsules were formed, while with linear macro-RAFT agents or with those exhibiting a high number of AA, full core–shell nanoparticles were obtained. For all the structures the control over the polymerization, the size, morphology, and zeta-potential as well as the photophysical properties were measured and compared with FNPs exhibiting a linear PEO-b-PAA block copolymer shell structure (C. Grazon, J. Rieger, R. Méallet-Renault, G. Clavier and B. Charleux, Macromol. Rapid Commun., 2011, 32, 699). Regardless of the shell structures, the brightness of the formed nanoparticles was estimated to be 100–1000 times higher than that of quantum dots. Ultimately, the shell of the different FNPs was functionalized with a second fluorophore via the AA's carboxyl groups. Thus, water-soluble ultra-bright FNPs with two fluorophores in distinct environments (water and in polystyrene) were obtained. They should have great potential for bioimaging applications.
    Mots-clés : POLE 4, POLYMERES.

  • B. Guan et R. B. Cole, « The Background to Electrospray », in The Encyclopedia of Mass Spectrometry, Boston: Elsevier, p. 132-140.
    Résumé : This article traces the development of electrospray back to its earliest beginnings. Many readers may be surprised to learn that descriptions of the electrostatic attraction of liquids to surfaces appear in the scientific literature as early as the year 1600, and that true electrospray experiments are documented to have been performed in the eighteenth century. Progress in the development of electrospray is detailed through these earliest observations and subsequent ingenious applications, mathematical descriptions, and, finally, coupling to mass analyzer instrumentation.
    Mots-clés : CSOB, Electrospray development, Electrospray history, Geoffrey Taylor, Harold Ransburg, Jean-Antoine Nollet, John Ellicott, John William Strutt, John Zeleny, Lord Kelvin, Lord Rayleigh, Malcolm Dole, POLE 3, Sir Thomas Browne, Stephen Gray, W. A. Macky, William Gilbert, William Henley, William Thomson.

  • S. Guelen, M. Blazejak, V. Mouriès-Mansuy, et L. Fensterbank, « From Enynyl Esters to Functionalized Polycyclic Derivatives via Cycloisomerization and Post-Functionalization », Synthesis, vol. 48, nᵒ 19, p. 3199-3206.
    Résumé : Thieme E-Books & E-Journals
    Mots-clés : MACO, POLE 1.

  • B. Habchi, S. Alves, A. Paris, D. N. Rutledge, et E. Rathahao-Paris, « How to really perform high throughput metabolomic analyses efficiently? », TrAC Trends in Analytical Chemistry, vol. 85, Part C, p. 128-139.
    Résumé : High-throughput analyses are based on technologies characterized by their rapidity, simplicity, sensitivity, robustness, low cost and high efficiency. They offer the potential for screening a large number of samples per day, which cannot be done using classical methods. High-throughput analyses have shown their feasibility and efficiency in multidisciplinary fields such as drug screening, bioassays of compound against mycobacteria. Another successful application is based on direct introduction mass spectrometry for the analysis of very complex organic materials in petroleomics. High-throughput analyses appear to be very attractive in metabolomics, which aims to study the interface between the chemical universe and biology, to detect general metabolic disruptions induced by external factors through a metabolite profiling approach. In this review, we focus on high-throughput metabolomics using high resolution mass spectrometry (HRMS). Specifically, performances and limits of available analytical techniques dedicated to high-throughput analyses, including sample introduction methods, HRMS and data processing tools are discussed.
    Mots-clés : CSOB, Data processing, DIMS, FTMS, High-throughput analyses, metabolomics, POLE 3.

  • X. Han, Y. Shi, L. Si, Z. Fan, H. Wang, R. Xu, P. Jiao, K. Meng, Z. Tian, X. Zhou, H. Jin, X. Wu, H. Chen, Y. Zhang, L. Zhang, S. Xiao, et D. Zhou, « Design, synthesis and biological activity evaluation of novel conjugated sialic acid and pentacyclic triterpene derivatives as anti-influenza entry inhibitors », MedChemCom, vol. 7, nᵒ 10, p. 1932-1945.
    Résumé : Influenza virus is a major human pathogen that causes annual epidemics and occasional pandemics. Recently, plant-derived pentacyclic triterpenes have been shown to act as highly potent anti-viral agents by efficiently preventing the attachment of the virion to the host cells. In this report, we conjugated sialic acid with oleanolic acid (OA), a natural product with broad antiviral entry activity, as well as three other analogs echinocystic acid (EA), ursolic acid (UA) and betulinic acid (BA). A total of 24 conjugated sialic acid and pentacyclic triterpene derivatives with different linkers were synthesized and evaluated for antiviral activity against influenza A/WSN/33 (H1N1) virus in MDCK cell culture. The most potent compound had an IC50 of 41.2 μM. Time-of-addition, hemagglutination inhibition (HI), surface plasmon resonance (SPR) and molecular docking assays demonstrated that compound 20a acted as an influenza virus entry inhibitor by preventing the binding of influenza virus hemagglutinin (HA) protein to host cells.
    Mots-clés : GOBS, POLE 3.

  • C. T. Howells, K. Marbou, H. Kim, K. J. Lee, B. Heinrich, S. J. Kim, A. Nakao, T. Aoyama, S. Furukawa, J. - H. Kim, E. Kim, F. Mathevet, S. Mery, I. D. W. Samuel, A. A. Ghaferi, M. S. Dahlem, M. Uchiyama, S. Y. Kim, J. W. Wu, J. - C. Ribierre, C. Adachi, D. - W. Kim, et P. André, « Enhanced organic solar cells efficiency through electronic and electro-optic effects resulting from charge transfers in polymer hole transport blends », Journal of Materials Chemistry, vol. 4, nᵒ 11, p. 4252-4263.
    Résumé : We demonstrate that blending fluorinated molecules in PEDOT:PSS hole transport layers (HTL) induces charge transfers which impact on both charge extraction and photogeneration within organic photovoltaic (OPV) devices. OPVs fabricated with modified HTL and two photoactive polymer blends led systematically to power conversion efficiencies (PCE) increases, with PTB7:PC70BM blend exhibiting PCE of ∼8.3%, i.e. ∼15% increase compared to pristine HTL devices. A reduced device-to-device characteristics variations was also noticed when fluorinated additives were used to modify the PEDOT:PSS. Shading lights onto the effect of HTL fluorination, we show that the morphology of the polymer:PCBM blends remains surprisingly unaffected by the fluorinated HTL surface energy but that, instead, the OPVs are impacted not only by the HTL electronic properties (work function, dipole layer, open circuit voltage, charge transfer dynamic) but also by alteration of the complex refractive indices (photogeneration, short circuit current density, external quantum efficiencies, electro-optic modelling). Both mechanisms find their origin in fluorination induced charge transfers. This work points towards fluorination as a promising strategy toward combining both external quantum efficiency modulation and power conversion efficiency enhancement in OPVs. Charge transfers could also be used more broadly to tune the optical constants and electric field distribution, as well as to reduce interfacial charge recombinations within OPVs.
    Mots-clés : POLE 4, POLYMERES.

  • L. Huder, C. Rinfray, D. Rouchon, A. Benayad, M. Baraket, G. Izzet, F. Lipp-Bregolin, G. Lapertot, L. Dubois, A. Proust, L. Jansen, et F. Duclairoir, « Evidence for Charge Transfer at the Interface between Hybrid Phosphomolybdate and Epitaxial Graphene », Langmuir, vol. 32, nᵒ 19, p. 4774-4783.
    Résumé : The interfacing of polyoxometalates and graphene can be considered to be an innovative way to generate hybrid structures that take advantage of the properties of both components. Polyoxometalates are redox-sensitive and photosensitive compounds with high temperature stability (up to 400 °C for some), showing tunable properties depending on the metal incorporated inside the complex. Graphene has a unique electronic band structure combined with good material properties for electrical and optical applications. The spontaneous, rather than electrochemical, functionalization of epitaxial graphene on SiC with Keggin phosphomolybdate derivative TBA3[PMo11O39{Sn(C6H4)C≡C(C6H4)N2}] (named KMoSn[N2+]) bearing a phenyl diazonium unit is investigated. Graphene decoration is evidenced by means of AFM, Raman, XPS, and cyclic voltammetry, indicating a successful immobilization of the polyoxomolybdate. The covalent bonding of the polyoxometalate to the graphene substrate can be deduced from the appearance of a D band in the Raman spectra and from the loss of mobility in the electrical conduction. High-resolution XPS spectra reveal an electron transfer from the graphene to the Mo complex. The comparison of charge-carrier density measurements before and after grafting supports the p-type doping effect, which is further evidenced by work function UPS measurements.
    Mots-clés : E-POM, POLE 2.

  • S. Humbert, G. Izzet, et P. Raybaud, « Competitive adsorption of nitrogen and sulphur compounds on a multisite model of NiMoS catalyst: A theoretical study », Journal of Catalysis, vol. 333, p. 78-93.
    Résumé : Using density functional theory including dispersion corrections, we establish a scale of enthalpies and Gibbs energies of adsorption of various organo-nitrogen molecules on a multisite model of the NiMoS active phase, which includes coordinatively unsaturated Lewis sites (Mo or Ni) and Brønsted –SH sites located on the M-edge and S-edge. Dispersion corrections and entropic effects are shown to impact significantly Gibbs energies of adsorption. In particular, protonation of pyridine derivatives is enhanced at high temperature on the Brønsted –SH sites of the M-edge and S-edge. For pyridine, a vibrational frequency analysis of the adsorption modes is undertaken. Stable adsorption configurations are identified for thiophene and 4,6-DMDBT on Lewis and Brønsted sites, and compared to N-containing molecules. While pyrrole derivatives are weak poisons of adsorption sites, pyridine derivatives are the stronger inhibitors. Furthermore, ammonia exhibits a non-negligible inhibitor character. We finally discuss the impact of inhibitors on 4,6-DMDBT hydrodesulphurization pathways.
    Mots-clés : 4,6-Dimethyldibenzothiophene, density functional theory, E-POM, Hydrodenitrogenation, Hydrodesulphurization, Inhibition, NiMoS, Nitrogen compounds, POLE 2, Vibrational modes.

  • B. Isare, S. Pensec, M. Raynal, et L. Bouteiller, « Bisurea-based supramolecular polymers: From structure to properties. », Comptes Rendus Chimie, vol. 19, nᵒ 1–2, p. 148-156, janv. 2016.
    Résumé : This review focuses on the synthesis, self-assembled structure and properties of bisurea-based supramolecular polymers. The straightforward synthetic accessibility of the bisurea synthon has allowed the systematic description of the relationship between the molecular structure and supramolecular assembly. Remarkably, these systems self-assemble at equilibrium into two competing supramolecular structures. Therefore, the assembly of low molar mass bisureas can lead to stimuli responsive viscoelastic gels as well as to systems which are able to report on weak intermolecular interactions. When deposited on surfaces, these hydrogen-bonded chains of molecules form well-organized monolayers in spite of defects from the substrate. Moreover, polymers with improved rheological or adhesive properties can be designed by grafting bisurea stickers.
    Mots-clés : Gels, monolayers, nanostructures, nanotubes, POLE 4, POLYMERES, Self-assembly, supramolecular chemistry, Thermodynamics.

  • G. Izzet, B. Abécassis, D. Brouri, M. Piot, B. Matt, S. A. Serapian, C. Bo, et A. Proust, « Hierarchical Self-Assembly of Polyoxometalate-Based Hybrids Driven by Metal Coordination and Electrostatic Interactions: From Discrete Supramolecular Species to Dense Monodisperse Nanoparticles », Journal of the American Chemical Society, vol. 138, nᵒ 15, p. 5093-5099.
    Résumé : The metal-driven self-assembly processes of a covalent polyoxometalate (POM)-based hybrid bearing remote terpyridine binding sites have been investigated. In a strongly dissociating solvent, a discrete metallomacrocycle, described as a molecular triangle, is formed and characterized by 2D diffusion NMR spectroscopy (DOSY), small-angle X-ray scattering (SAXS), and molecular modeling. In a less dissociating solvent, the primary supramolecular structure, combining negatively charged POMs and cationic metal linkers, further self-assemble through intermolecular electrostatic interactions in a reversible process. The resulting hierarchical assemblies are dense monodisperse nanoparticles composed of ca. 50 POMs that were characterized by SAXS and transmission electron microscopy (TEM). This multiscale organized system directed by metal coordination and electrostatic interactions constitutes a promising step for the future design of POM self-assemblies with controllable structure-directing factors.
    Mots-clés : E-POM, POLE 2.

  • J. Jacquet, S. Blanchard, E. Derat, M. D. - E. Murr, et L. Fensterbank, « Redox-ligand sustains controlled generation of CF3 radicals by well-defined copper complex », Chemical Science, vol. 7, nᵒ 3, p. 2030-2036.
    Résumé : A well-defined copper complex bearing iminosemiquinone ligands performs single electron reduction of an electrophilic CF3+ source into CF˙3 radicals. This redox behavior is enabled by the ligand which shuttles through two different redox states (iminosemiquinone and iminobenzoquinone) while the copper center is preserved as a Cu(II). This system was used in the trifluoromethylation of silyl enol ethers, heteroaromatics and in the hydrotrifluoromethylation of alkynes. This is the first example of cooperative redox catalysis for the controlled generation of CF˙3 radicals.
    Mots-clés : E-POM, MACO, POLE 1, POLE 2.

  • J. Jacquet, P. Chaumont, G. Gontard, M. Orio, H. Vezin, S. Blanchard, M. Desage-El Murr, et L. Fensterbank, « C−N Bond Formation from a Masked High-Valent Copper Complex Stabilized by Redox Non-Innocent Ligands », Angewandte Chemie International Edition, vol. 55, nᵒ 36, p. 10712-10716, 2016.
    Résumé : The reactivity of a stable copper(II) complex bearing fully oxidized iminobenzoquinone redox ligands towards nucleophiles is described. In sharp contrast with its genuine low-valent counterpart...
    Mots-clés : E-POM, MACO, POLE 1, POLE 2.

  • S. F. Jafri, E. S. Koumousi, P. Sainctavit, A. Juhin, V. Schuler, O. Bunǎu, D. Mitcov, P. Dechambenoit, C. Mathonière, R. Clérac, E. Otero, P. Ohresser, C. Cartier dit Moulin, et M. - A. Arrio, « Large Orbital Magnetic Moment Measured in the [TpFeIII(CN)3]− Precursor of Photomagnetic Molecular Prussian Blue Analogues », Inorganic Chemistry, vol. 55, nᵒ 14, p. 6980-6987, juill. 2016.

  • F. Jaroschik, A. Simonneau, G. Lemière, K. Cariou, N. Agenet, H. Amouri, C. Aubert, J. - P. Goddard, D. Lesage, M. Malacria, Y. Gimbert, V. Gandon, et L. Fensterbank, « Assessing Ligand and Counterion Effects in the Noble Metal Catalyzed Cycloisomerization Reactions of 1,6-Allenynes: a Combined Experimental and Theoretical Approach », ACS Catalysis, vol. 6, nᵒ 8, p. 5146-5160.
    Résumé : 1,6-Allenynes are useful mechanistic probes in noble-metal catalysis, since they can give rise to very distinct products in a highly selective fashion. Various cycloisomerization reactions have been described, and discrete mechanisms have been postulated. Of particular interest, whereas Alder-ene types of products can be obtained in a variety of ways using noble-metal catalysts (Au, Pt, Rh, ...), hydrindienes have been reported solely with gold and platinum under specific conditions. It was shown in a previous study that this intriguing transformation required the presence of chloride ligands at the active catalytic species. Herein, the factors governing the fate of 1,6-allenynes under cycloisomerization conditions have been studied more thoroughly, revealing a much more complex scenario. The nature of ligands, counterions, and metals was examined, showing that hydrindienes can be isolated in the absence of halides, using electron-rich, bulky triorganophosphines or carbene ligands. This crucial finding could also be used to access hydrindienes in high yields, not only with gold or platinum but also with silver. On the basis of mass spectrometry, NMR spectroscopy, and computations, refined mechanistic scenarios have been put forward, also rationalizing counterion effects. Notably, a metal vinylidene intermediate has been proposed for the formation of the hydrindiene derivatives. Finally, in the presence of tris((triphenylphosphine)gold)oxonium tetrafluoroborate as catalyst, a new pathway has been unveiled, involving gold alkyne σ,π complexes and leading to previously unobserved [2 + 2] cycloaddition compounds.
    Mots-clés : ARC, CSOB, MACO, POLE 1, POLE 2, POLE 3.

  • J. - R. Jiménez, A. Mondal, L. - M. Chamoreau, P. Fertey, F. Tuna, M. Julve, A. Bousseksou, R. Lescouëzec, et L. Lisnard, « An {Fe60 } tetrahedral cage: building nanoscopic molecular assemblies through cyanometallate and alkoxo linkers », Dalton Transactions, 2016.

  • Z. Ku, N. H. Tiep, B. Wu, T. C. Sum, D. Fichou, et H. J. Fan, « Solvent engineering for fast growth of centimetric high-quality CH3NH3PbI3 perovskite single crystals », New Journal of Chemistry, vol. 40, nᵒ 9, p. 7261-7264.
    Résumé : Centimetre-scale CH3NH3PbI3 perovskite single crystals of high structural quality are grown by a new versatile method based on the use of a binary solvent mixture at a temperature as low as 70 degrees C. The growth rate is fast enough for a millimeter scale seed crystal to grow to the centimeter scale in a few hours.
    Mots-clés : crystallization, deposition, diffusion, electron, lead iodide perovskite, NASCO, organometal halide perovskites, performance, POLE 2, room-temperature, sensitized solar-cell, v hysteresis.

  • S. H. Kyne, C. Lévêque, S. Zheng, L. Fensterbank, A. Jutand, et C. Ollivier, « Iron(II) catalyzed reductive radical cyclization reactions of bromoacetals in the presence of NaBH4: optimization studies and mechanistic insights », Tetrahedron, vol. 72, nᵒ 48, p. 7727-7737.
    Résumé : 5-Exo-trig radical reductive cyclization reactions of bromoacetals are catalyzed by iron in the presence of the reducing agent NaBH4. Both iron(II) and iron(III) were found to effectively mediate these reactions. As shown by cyclic voltammetry, iron(III) can be reduced to an iron(II) precatalyst before passing through an identical reaction mechanism in which monoelectronic activation of the substrate would occur by an anionic hydridoiron(I) complex. Further studies have established that both the substrate (iodo- vs bromo-derivative) and the precatalytic mixture are decisive in determining the reaction outcome.
    Mots-clés : Electrochemistry, Homogenous catalysis, iron, MACO, NMR spectroscopy, POLE 1, Radical cyclization, reduction.

  • P. - H. Lanoë, J. Chan, G. Gontard, F. Monti, N. Armaroli, A. Barbieri, et H. Amouri, « Deep-Red Phosphorescent Iridium(III) Complexes with Chromophoric N-Heterocyclic Carbene Ligands: Design, Photophysical Properties, and DFT Calculations (Eur. J. Inorg. Chem. 11/2016) », European Journal of Inorganic Chemistry, vol. 2016, nᵒ 11, p. n/a-n/a.
    Mots-clés : ARC, Carbene ligands, Charge transfer, Iridium, luminescence, Photophysics, POLE 1.

  • J. Lazko, T. Sénéchal, A. Bouchut, Y. Paint, L. Dangreau, A. Fradet, M. Tessier, J. M. Raquez, et P. Dubois, « Acid-free extraction of cellulose type I nanocrystals using Brønsted acid-type ionic liquids », Nanocomposites, vol. 2, nᵒ 2, p. 65-75.
    Résumé : Extraction of cellulose type I nanocrystals from cotton fibers was straightforwardly carried out using exclusively Brønsted acid-type ionic liquids (ILs) via a two-step swelling/hydrolysis route, the switch between these two stages being induced by water addition. Since the whole process was achieved in a single reaction medium predominantly based on 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) and 1-(4-sulfobutyl)-3-methylimidazolium hydrogen sulfate ([SBMIM]HSO4), the process parameters were investigated in order to ensure a perfect compatibility and sequencing towards the two-step route proposed here. The impacts on nanoparticle morphology, crystallinity evolution, and cellulose type I to type II denaturation were observed under field-emission gun scanning electron microscopy and corroborated by X-ray diffraction characterizations. ILs recovery and reuse were also demonstrated, opening up new prospects of conception of multi-cycle, environmentally and economically sustainable processes.
    Mots-clés : Cellulose nanocrystals, hydrolysis, Ionic liquids, POLE 4, POLYMERES, Recycling, Swelling.

  • S. Le Liepvre, P. Du, D. Kreher, F. Mathevet, A. - J. Attias, C. Fiorini-Debuisschert, L. Douillard, et F. Charra, « Fluorescent Self-Assembled Molecular Monolayer on Graphene », ACS Photonics, vol. 3, nᵒ 12, p. 2291-2296, déc. 2016.
    Résumé : We report the first fluorescent molecular self-assembly on graphene. The quenching of the fluorescence of the adsorbed dye by the adjacent graphene is hindered at the molecular scale based on a spacer approach, through a specifically designed dual-functionalized self-assembling building block. This 3D tecton presents two faces, one forming a noncovalent graphene-binding pedestal and the other carrying a dye group linked by a spacer to the pedestal. The spontaneous ordering of the adsorbed layer is investigated by scanning tunneling microscopy, whereas the resulting optical properties of the whole graphene–dye hybrid system are characterized by absorption and fluorescence spectroscopies.
    Mots-clés : POLE 4, POLYMERES.

  • D. Lebœuf, L. Marin, B. Michelet, A. Perez-Luna, R. Guillot, E. Schulz, et V. Gandon, « Harnessing the Lewis Acidity of HFIP through its Cooperation with a Calcium(II) Salt: Application to the Aza-Piancatelli Reaction », Chemistry - A European Journal, vol. 22, nᵒ 45, p. 16165-16171.
    Résumé : A method to extend the scope of the aza-Piancatelli reaction between 2-furylcarbinols and anilines is depicted. We found that 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) is the solvent of choice for this transformation, as it outcompetes the usual solvents in terms of rate and yield. Side reactions and other issues raised by the title reaction are prevented, thereby providing an avenue to complex molecules that were previously inaccessible. Lewis acidity studies and computations were carried out to unveil the role of HFIP. Based on these results, we propose that HFIP is, in fact, acting as a Lewis acid and that its acidity can be enhanced when combined with a calcium(II) salt.
    Mots-clés : alcohol, Calcium, cooperative catalysis, density functional calculations, electrocyclic reactions, POLE 1, ROCS.

  • K. J. Lee, J. H. Woo, E. Kim, Y. Xiao, X. Su, L. M. Mazur, A. - J. Attias, F. Fages, O. Cregut, A. Barsella, F. Mathevet, L. Mager, J. W. Wu, A. D'Aléo, et J. - C. Ribierre, « Electronic energy and electron transfer processes in photoexcited donor–acceptor dyad and triad molecular systems based on triphenylene and perylene diimide units », Physical Chemistry Chemical Physics, vol. 18, nᵒ 11, p. 7875-7887.
    Résumé : We investigate the photophysical properties of organic donor–acceptor dyad and triad molecular systems based on triphenylene and perylene diimide units linked by a non-conjugated flexible bridge in solution using complementary optical spectroscopy techniques. When these molecules are diluted in dichloromethane solution, energy transfer from the triphenylene to the perylene diimide excited moieties is evidenced by time-resolved fluorescence measurements resulting in a quenching of the emission from the triphenylene moieties. Simultaneously, another quenching process that affects the emission from both donor and acceptor units is observed. Solution ultrafast transient absorption measurements provide evidence of photo-induced charge transfer from either the donor or the acceptor depending upon the excitation. Overall, the analysis of the detailed time-resolved spectroscopic measurements carried out in the dyad and triad systems as well as in the triphenylene and perylene diimide units alone provides useful information both to better understand the relations between energy and charge transfer processes with molecular structures, and for the design of future functional dyad and triad architectures based on donor and acceptor moieties for organic optoelectronic applications.
    Mots-clés : POLE 4, POLYMERES.

  • K. J. Lee, J. H. Woo, Y. Xiao, E. Kim, L. M. Mazur, D. Kreher, A. - J. Attias, K. Matczyszyn, M. Samoc, B. Heinrich, S. Méry, F. Fages, L. Mager, A. D'Aléo, J. W. Wu, F. Mathevet, P. André, et J. - C. Ribierre, « Structure–charge transfer property relationship in self-assembled discotic liquid-crystalline donor–acceptor dyad and triad thin films », RCS Advances, vol. 6, nᵒ 63, p. 57811-57819.
    Résumé : The photophysical properties of donor–acceptor (D–A) and donor–acceptor–donor (D–A–D) liquid crystalline dyads and triads based on two different discotic mesogens are examined in thin films by steady-state optical spectroscopy and subpicosecond transient absorption measurements. In these systems, triphenylene and perylene bisimide units are covalently linked by flexible decyloxy chain(s) and act as an electron donor (D) and acceptor (A), respectively. These discotic liquid-crystalline systems form well-separated D and A π-stacked columnar structures in thin films. The absorption spectra of the films indicate an aggregation of the perylene bisimide and triphenylene moieties along the columns. Steady-state photoluminescence measurements show a strong fluorescence quenching that is mainly attributed to a photo-induced charge transfer process taking place between the triphenylene and perylene bisimide units. Subpicosecond transient absorption measurements show that the photoinduced charge transfer (CT) states in the dyad and triad films are formed within 0.3 ps and recombine on a 150–360 ps time scale. In addition, a correlation between the dynamics of the charge recombination process and the spacing distances between D and A units can be established in the dyad and triad films. This study provides important information on the relationship between molecular packing and the charge transfer properties in such self-organized D and A columnar nanostructures.
    Mots-clés : POLE 4, POLYMERES.

  • D. Lesage, J. Blu, J. - C. Tabet, et Y. Gimbert, « Intermolecular versus intramolecular Pauson-Khand reaction in gas phase: Limitation and feasibility », Journal of Organometallic Chemistry, vol. 809, p. 7-13.

  • C. Lévêque, L. Chenneberg, V. Corcé, J. - P. Goddard, C. Ollivier, et L. Fensterbank, « Primary alkyl bis-catecholato silicates in dual photoredox/nickel catalysis: aryl- and heteroaryl-alkyl cross coupling reactions », Organic Chemistry Frontiers, vol. 3, nᵒ 4, p. 462-465.

  • C. Lévêque, L. Chenneberg, V. Corcé, C. Ollivier, et L. Fensterbank, « Organic photoredox catalysis for the oxidation of silicates: applications in radical synthesis and dual catalysis », Chemical Communications, vol. 52, nᵒ 64, p. 9877-9880.
    Résumé : Metal free photooxidation of alkyl bis(catecholato)silicates with the organic dye 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyano-benzene (4CzIPN) allows the smooth formation of alkyl radicals. The latter can be efficiently engaged either with radical acceptors to provide homolytic addition products or in photoredox/nickel dual catalysis reactions to obtain cross-coupling products.
    Mots-clés : MACO, POLE 1.

  • X. - C. Liu, Z. - Y. Zhu, Y. - L. Tang, M. -fei Wang, Z. Wang, A. - J. Liu, et Y. - M. Zhang, « Structural properties of polysaccharides from cultivated fruit bodies and mycelium of Cordyceps militaris », Carbohydrate Polymers, vol. 142, p. 63-72.
    Résumé : The structural properties of polysaccharides, respectively, obtained from the fermented mycelium and cultivated fruiting bodies of the Cordyceps militaris were investigated and compared in this paper. First, the crude polysaccharides were extracted from the mycelium and the fruiting bodies, respectively. The polysaccharides were successively purified by Sevag and chromatography on Sephadex G-100 column to produce two polysaccharides fractions termed CMPS-II and CBPS-II, respectively. The average molecular weights of CMPS-II and CBPS-II were 1.402×10(3) kDa and 1.273×10(3) kDa, respectively, and they were mainly composed of mannose, glucose and galactose in the mole ratios of 1:28.63:1.41 and 1:12.41:0.74, respectively, for CMPS-II and CBPS-II. Afterward, the structural features of CMPS-II and CBPS-II were investigated by a combination of chemical and instrumental analysis, such as FT-IR, periodate oxidation-Smith degradation, GC-MS, NMR and methylation analysis. The results indicated that structurally, both CMPS-II and CBPS-II were 1,3-branched-galactomannoglucan that had a linear backbone of (1→4)-linked α-D-glucopyranose (Glcp). Congo-red test revealed that CMPS-II and CBPS-II existed as triple-helical chains in 0.05-0.15 M NaOH solution.
    Mots-clés : Cordyceps militaris, GOBS, POLE 3, Polysaccharide, structure.

  • Z. Liu, Q. Zheng, W. Chen, S. Man, Y. Teng, X. Meng, Y. Zhang, P. Yu, et W. Gao, « Paris saponin I inhibits proliferation and promotes apoptosis through down-regulating AKT activity in human non-small-cell lung cancer cells and inhibiting ERK expression in human small-cell lung cancer cells », RCS Advances, vol. 6, nᵒ 75, p. 70816-70824.
    Résumé : Paris Saponin I (PSI), a steroidal saponin derivative extracted from a traditional Chinese herbal Paris polyphylla, has shown cytotoxic effects on several tumor cell lines. However, the mechanisms of its antitumor activity especially for lung cancers remain to be elucidated. In this present investigation, we continue to explore the efficacy and mechanisms underlying the cytotoxic effects of PSI in lung cancer cell lines. Three non-small cell lung cancer (NSCLC) cells (H1299, H520, H460) and one small cell lung cancer (SCLC) cell (H446) were treated with PSI for the first time. PSI significantly induced cell cycle arrest at the G2/M phase and mitochondrial-related apoptosis NSCLC cells but not SCLC cells. Additionally, PSI reduced phosphorylation of AKT in NSCLC and ERK in SCLC in general. Interestingly, we observed that PSI influenced different signaling pathways among the four kinds of lung cancer cells. After PSI treatment, p38 MAPK and ERK activation were observed in H1299, while p38 MAPK increased and JNK decreased in H520. On the contrary, we found JNK activation in H460 cells with PSI. However, PSI upregulated the AKT activity and inhibited the JNK expression in H446 cells. The results indicate that PSI exhibits the cytotoxicity in different pathways depending on the cancer types.
    Mots-clés : GOBS, POLE 3.

  • A. Lombana, C. Rinfray, F. Volatron, G. Izzet, N. Battaglini, S. Alves, P. Decorse, P. Lang, et A. Proust, « Surface Organization of Polyoxometalate Hybrids Steered by a 2D Supramolecular PTCDI/Melamine Network », The Journal of Physical Chemistry C, vol. 120, nᵒ 5, p. 2837-2845.
    Résumé : A 2D supramolecular honeycomb network built on hydrogen bonding of perylene-3,4,9,10-tetracarboxylic acid diimide (PTCDI) and 1,3,5-triazine-2,4,6-triamine (Melamine) has been self-assembled on Au(111) by a solution processed method. The ability of the porous network to host functional molecular oxides or polyoxometalates (POMs) has been investigated using a functionalized species [PW11O39Ge{p-C6H4-C≡C–C6H4-NHC(O) (CH2)4{-CH(CH2)2S-S-}}]4– (KWGe[S-S]): this inorganic/organic hybrid built on a Keggin-type POM core and an organic tether incorporating a thioctic acid function has been designed to enhance the host–guest interaction by the formation of covalent Au–S bonds. XPS analysis confirmed the presence of the POMs that are covalently held onto the surface. Probed by STM operating under ambient conditions, the spatial organization of the POMs display some reminiscence of the organic template, while monitoring the POM deposition at various immersion times by PM-IRRAS showed that the POM raising at the substrate is fostered.
    Mots-clés : CSOB, E-POM, POLE 2, POLE 3.

  • M. M. Lorion, F. J. S. Duarte, M. J. Calhorda, J. Oble, et G. Poli, « Opening the Way to Catalytic Aminopalladation/Proxicyclic Dehydropalladation: Access to Methylidene γ-Lactams », Organic Letters, vol. 18, nᵒ 5, p. 1020-1023.
    Résumé : A new aerobic intramolecular palladium(II)-based catalytic system that triggers aminopalladation/dehydropalladation of N-sulfonylalkenylamides to give the corresponding methylidene γ-lactams has been identified. Use of triphenylphosphine and chloride anion as ligands is mandatory for optimal yields, and molecular oxygen can be used as the sole terminal oxidant. Scope and limitations of the methods are described. A mechanism is proposed on the basis of experimental results as well as density functional theory calculations.
    Mots-clés : POLE 1, ROCS.

  • M. M. Lorion, C. Kammerer, G. Prestat, et G. Poli, « Sequential Pd-catalyzed allylic alkylation / Ru-catalyzed ring-closing metathesis, », in Comprehensive Organic Chemistry Experiments for the Laboratory Classroom, C. A. M. Afonso, N. R. Candeias, D. P. Simao, A. F. Trindade, J. A. S. Coelho, et B. Tan, Éd. Royal Society of Chemistry Press, p. 650-655.
    Résumé : This expansive and practical textbook contains organic chemistry experiments for teaching in the laboratory at the undergraduate level covering a range of functional group transformations and key organic reactions.The editorial team have collected contributions from around the world and standardized them for publication. Each experiment will explore a modern chemistry scenario, such as: sustainable chemistry; application in the pharmaceutical industry; catalysis and material sciences, to name a few. All the experiments will be complemented with a set of questions to challenge the students and a section for the instructors, concerning the results obtained and advice on getting the best outcome from the experiment. A section covering practical aspects with tips and advice for the instructors, together with the results obtained in the laboratory by students, has been compiled for each experiment.Targeted at professors and lecturers in chemistry, this useful text will provide up to date experiments putting the science into context for the students.
    Mots-clés : POLE 1, ROCS.

  • M. M. Lorion, J. Oble, et G. Poli, « Palladium catalyzed oxidative aminations and oxylations: where are we? », Pure and Applied Chemistry, vol. 88, nᵒ 4, p. 381–389.
    Résumé : Selective product formation in the Pd-catalyzed cyclization of unsaturated amide and carboxylic acid derivatives is an intriguing and challenging task. We recently discovered that the oxidative intramo-lecular Pd(II)-catalyzed amination or oxylation of unsaturated N-sulfonyl carbamates, N-sulfonyl carbox-amides and carboxylic acids takes place through the involvement of cyclic (usually, 5-or 6-membered) aminopalladated (AmPIs) or oxypalladated (OxPI) intermediates. Such cyclic intermediates can undergo a variety of transformations such as distocyclic β-H elimination, oxidative acetoxylation or intramolecular car-bopalladation, depending upon the substrate and/or the reaction conditions. In the absence of appropriate reaction pathways, the cyclic nucleopalladated intermediates (NuPIs) simply engage in an inconsequential equilibrium with the initial substrate and other transformations occur such as allylic C–H activation or, in the particular case of allyl carbamates, [3,3]-sigmatropic rearrangement.
    Mots-clés : POLE 1, ROCS.

  • R. Maazaoui, M. Pin-Nó, K. Gervais, R. Abderrahim, F. Ferreira, A. Perez-Luna, F. Chemla, et O. Jackowski, « Domino Methylenation/Hydrogenation of Aldehydes and Ketones by Combining Matsubara's Reagent and Wilkinson's Catalyst », European Journal of Organic Chemistry, p. 5732-5737.
    Résumé : The methylenation/hydrogenation cascade reaction of aldehydes or ketones through a domino process involving two ensuing steps in a single pot is realized. The compatibility of Matsubara's reagent and Wilkinson's complex give a combination that allows, under dihydrogen, the transformation of a carbonyl function into a methyl group. This new method is suitable to introduce an ethyl motif from aromatic and aliphatic aldehydes with total chemoselectivity and total retention of α-stereochemical purity. The developed procedure is also extended to the introduction of methyl groups from ketones.
    Mots-clés : aldehydes, chemoselectivity, domino reactions, hydrogenation, ketones, Methylenation, POLE 1, ROCS.

  • N. Mansour, K. Hriz, N. Jaballah, D. Kreher, et M. Majdoub, « Synthesis, characterization, optical and electrical properties of bis(phenylvinyl)anthracene-based polymers », Optical Materials, vol. 58, p. 296-305, 2016.
    Résumé : A series of bis(phenylvinyl)anthracene-based polymers containing different lengths of polar ethylene glycol groups in the main chain (P1–3) were efficiently synthesized by Wittig polycondensation. These polymers are fully soluble in volatile solvents, which helped a lot to obtain high quality films. Moreover, these semi-conducting materials exhibited semi-crystalline morphology with relatively high glass transition temperature. In this article, the UV–visible absorption and fluorescence properties of P1–3 were studied consequently both in solution and as thin solid film: tan absorption-onset at 433 nm was observed and all these bis(phenylvinyl)anthracene-based polymers (P1–3) show a blue emission in solution, fluorescence quantum efficiencies being respectively 52% for P1, 75% for P2 and 67% for P3. In addition, the HOMO/LUMO energy levels were evaluated by cyclic voltammetry measurements and indicate a p-type semi-conducting materials. Finally, the electrical properties of P1–3 were investigated by recording current-tension characteristics and these experimental results were modeled by the current space-charge-limited (SCLC) mechanism.
    Mots-clés : Anthracene, Optical properties, Organic thin layer, POLE 4, polymer synthesis, POLYMERES, Semi-conducting polymer, Space-charge limited current (SCLC).

  • A. Martin, A. Arda, J. Désiré, A. Martin-Mingot, N. Probst, P. Sinaÿ, J. Jiménez-Barbero, S. Thibaudeau, et Y. Blériot, « Catching elusive glycosyl cations in a condensed phase with HF/SbF5 superacid », Nature Chemistry, vol. 8, nᵒ 2, p. 186-191.
    Résumé : Glycosyl cations are universally accepted key ionic intermediates in the mechanism of glycosylation, the reaction that covalently links carbohydrates to other molecules. These ions have remained hypothetical species so far because of their extremely short life in organic media as a consequence of their very high reactivity. Here, we report the use of liquid hydrofluoric acid–antimony pentafluoride (HF/SbF5) superacid to generate and stabilize the glycosyl cations derived from peracetylated 2-deoxy and 2-bromoglucopyranose in a condensed phase. Their persistence in this superacid medium allows their three-dimensional structure to be studied by NMR, aided by complementary computations. Their deuteration further confirms the impact of the structure of the glycosyl cation on the stereochemical outcome of its trapping.
    Mots-clés : Carbohydrate chemistry, GOBS, POLE 3, Structure elucidation.

  • T. Matsushima, F. Mathevet, B. Heinrich, S. Terakawa, T. Fujihara, C. Qin, A. S. D. Sandanayaka, J. - C. Ribierre, et C. Adachi, « N-channel field-effect transistors with an organic-inorganic layered perovskite semiconductor », Applied Physics Letters, vol. 109, nᵒ 25, p. 253301.

  • L. Meziane, C. Salzemann, C. Aubert, H. Gérard, C. Petit, et M. Petit, « Hcp cobalt nanocrystals with high magnetic anisotropy prepared by easy one-pot synthesis », Nanoscale, vol. 8, nᵒ 44, p. 18640-18645, nov. 2016.
    Résumé : Herein we describe the first synthesis of pure mono-disperse spherical hcp-nanocrystals ferromagnetic at room temperature. Our strategy, based on the simple combination of oleylamine and ClCo(PPh3)3, allows the one-pot synthesis of size-controlled hcp-nanocrystals. The size and shape of the nanocrystals can be tuned by varying the reaction time or the concentration.
    Mots-clés : MACO, POLE 1.

  • I. Minguez-Bacho, S. Rodriguez-Lopez, A. Climent-Font, D. Fichou, M. Vazquez, et M. Hernandez-Velez, « Variation of the refractive index by means of sulfate anion incorporation into nanoporous anodic aluminum oxide films », Microporous and Mesoporous Materials, vol. 225, p. 192-197.
    Résumé : The variation in the refractive index of nanoporous anodic aluminum oxide (AAO) films regarding the sulfur anion incorporation is studied in this work. For this purpose, different samples are grown under potentiostatic conditions at different voltages and concentrations of sulfuric acid in the electrolyte. The samples are analyzed by Rutherford backscattering spectroscopy and infrared spectrometry, confirming the presence of sulfate anions and water embedded into the nanoporous MO films. The incorporation of. sulfate ions into the alumina matrix varies from 63 up to 11.7% regarding aluminum content. We have studied Fabry-Perot optical interferences by shining incident monochromatic light in specular reflectance conditions. The reflected monochromatic light waves interact in internal reflectivity generating constructive and destructive interferences known as Fabry-Perot optical interferences. An iterative method based on the equation for constructive interferences conditions in thin films and Snell equations is developed in order to calculate the refractive index of the nanoporous AAO films as a function of the wavelength. The calculated refractive indices increase when the sulfur content of the nanoporous MO films decreases. The variation of the calculated refractive index is 0.08 and remains constant in the wavelength range 400-1200 nm. (C) 2015 Elsevier Inc. All rights reserved.
    Mots-clés : Anion incorporation, electrolyte, Fabry-Perot interferences, membranes, nanohole arrays, Nanoporous anodic alumina, nanotube arrays, NASCO, optical-properties, POLE 2, porous alumina, Refractive index, templates, thin-films, transmission, volume expansion.

  • R. Mokhtari, A. Adkhis, O. Berradj, F. Michaud, Y. Rousselin, et S. Top, « Synthesis, spectroscopic, and X-ray structural study of aqua-bis(thymine-N 1 ,N 4 )-ethylenediamine copper(II)dihydrate [Cu(Thy) 2 (en)(H 2 O)].2H 2 O », Inorganic and Nano-Metal Chemistry, vol. 47, nᵒ 6, p. 841 - 844, 2016.

  • M. Mon, T. Grancha, M. Verdaguer, C. Train, D. Armentano, et E. Pardo, « Solvent-Dependent Self-Assembly of an Oxalato-Based Three Dimensional Magnet Exhibiting a Novel Architecture », Inorganic Chemistry, vol. 55, nᵒ 14, p. 6845-6847.
    Résumé : The old but evergreen family of bimetallic oxalates still offers innovative and intetesting results. When (Me4N)(3)[Cr(ox)(3)]center dot 3H(2)O is reacted with Mn-II ions in a noriaqueous solvent, A novel three-dimensional magnet Of the formula [N(CH3)(4)](6)[Mn(3)Ct(4)(ox)(12)]center dot 6CH(3)OH is obtained instead of the one-dimensional compound obtained in water. This new material exhibits an unprecedented stoichiometry with a binodal (3,4) net topology and the highest critical temperature (T-C = 7 K) obsetved so fat in a iananese-chromium oxalate based magnet.
    Mots-clés : cations, complex, conductivity, coordination polymers, crystal, design, framework, HorsPole, m-ii, molecule-based magnets, networks.

  • J. Moussa, L. M. Chamoreau, M. P. Gullo, A. D. Esposti, A. Barbieri, et H. Amouri, « Induced phosphorescence from Pt → Ag and Ag(I)⋯Ag(I) metallophilic interactions in benzenedithiolatodiimine-Pt2/Ag2 clusters: a combined experimental and theoretical investigation », Dalton Transactions, vol. 45, nᵒ 7, p. 2906-2913.
    Résumé : We report the synthesis and luminescence properties of a novel platinum(II)–silver(I) cluster exhibiting supramolecular donor–acceptor dative Pt → Ag bonds as well as d10⋯d10 argentophilic interactions. This compound was obtained by a self-assembly process upon mixing silver triflate with the [Pt(bdt)(bpy)] (1) building block. The new compound was characterized by infrared, NMR (1H, 13C) and UV-vis spectroscopy. In addition, the molecular structure was unequivocally ascertained by a single-crystal X-ray diffraction study and shows that the assembly is identified as [(Pt2Ag2(o-bdt)2(bpy)2](CF3SO3)2 (2). Remarkably, the structure shows that complex 2 exists as two isomers I and II displaying different types of argentophilic interactions Ag⋯Ag as well as Pt → Ag dative bonds. These interactions are highly important and turn on phosphorescent emissions at low temperature depending on the nature of the isomer. The photophysical properties of both isomers were investigated and rationalized through TD-DFT calculations. This work paves the way to the synthesis of novel supramolecular assemblies displaying peculiar properties imparted from metallophilic as well as donor–acceptor metal–metal interactions.
    Mots-clés : ARC, POLE 1.

  • J. Moussa, G. R. Freeman, J. A. G. Williams, L. - M. Chamoreau, P. Herson, et H. Amouri, « Synthesis and Luminescence Properties of Cycloplatinated Complexes with a Chelating N∧C Pyridine-Derived N-Heterocyclic Carbene – Influence of 2,4,6-Triphenyl­phosphinine versus Triphenylphosphine », European Journal of Inorganic Chemistry, vol. 2016, nᵒ 5, p. 761-767.
    Résumé : Two cycloplatinated complexes of the form [Pt(NC)CH3(P)]+ incorporating a rare, bidentate NC-chelating pyridylpyridylidene ligand are reported. The phosphorus-based ligand P is either 2,4,6-triphenylphosphinine or triphenylphosphine. These mononuclear complexes have been fully characterised in solution and by single-crystal X-ray diffraction analysis. UV/Vis absorption and photoluminescence spectroscopy studies reveal strong phosphorescence from the phosphinine compound at 77 K but no emission from its triphenylphosphine analogue. This contrasting behaviour can be traced to the π-acceptor ability of the phosphabenzene ring, as corroborated by electrochemical and time-dependent DFT (TD-DFT) calculations.
    Mots-clés : ARC, Carbene ligands, luminescence, N li­gands, Phosphinines, Platinum, POLE 1.

  • J. Moussa, K. Haddouche, L. - M. Chamoreau, H. Amouri, et J. A. G. Williams, « New N^C^N-coordinated Pd(II) and Pt(II) complexes of a tridentate N-heterocyclic carbene ligand featuring a 6-membered central ring: synthesis, structures and luminescence », Dalton Transactions, vol. 45, nᵒ 32, p. 12644-12648.
    Résumé : We describe Pd(II) and Pt(II) complexes of an N^C^N-coordinating pincer-like ligand featuring two lateral pyridine rings and a 6-membered carbene core. Their crystal structures display 1-dimensional chains with short π–π and M(II)⋯M(II) interactions. Such interactions also impact on the photophysical properties, with the Pt(II) complex being luminescent in the solid state at room temperature.
    Mots-clés : ARC, POLE 1.

  • Y. Nie, M. Zhong, Z. Jiang, J. Sun, Y. Gao, F. Ding, H. Li, Y. Zhang, et X. He, « Synthesis and potential anticonvulsant activity of new aryl sulfonyl semicarbazide derivatives », Medicinal Chemistry Research, vol. 25, nᵒ 7, p. 1425-1432.
    Résumé : In the present study on the development of new anticonvulsants, twelve new aryl sulfonyl semicarbazide derivatives were synthesized and tested for anticonvulsant activity using maximal electroshock (MES), subcutaneous pentylenetetrazole screens. Their neurotoxicity was determined by the rotorod test. The most active compound 5i showed the MES-induced seizures with ED50 value of 7.3 mg/kg and TD50 value of 402.3 mg/kg after intraperitoneally injection to mice, which provided compound 5i with a protective index (TD50/ED50) of 55.1 in the MES test.
    Mots-clés : GOBS, POLE 3.

  • R. Piccardi, L. Micouin, et O. Jackowski, « The Chemistry of Alkynylaluminum Species », in PATAI'S Chemistry of Functional Groups, I. Marek, Éd. John Wiley & Sons, Ltd, p. 1-47.
    Résumé : Among organoaluminum reagents, alkynylaluminum species exhibit peculiar physicochemical properties and reactivity. Depending on the nature of easily controlled parameters such as substituents on the aluminum center or additives and solvent, their Lewis acidity and nucleophilicity can be independently fine-tuned in a very precise manner. This chapter describes the preparation of alkynylaluminum compounds, their structure, and their reactivity in several synthetic transformations involving the transfer of their alkynyl group such as nucleophilic substitution reactions, additions to C–X multiple bonds, epoxide and aziridine ring-opening reactions, reactions with oxonium and iminium species, metal-assisted cross-coupling reactions, as well as in rearrangements. The reactivity of the triple bond of these reagents is also presented.
    Mots-clés : acetylides, alanates, alanes, alkynylaluminum, Lewis acidity, POLE 1, ROCS, triethylaluminum, trimethylaluminum.

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