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  • M. Abdellaoui, A. Millanvois, E. Levernier, C. Ollivier, et L. Fensterbank, « Visible-Light-Mediated Z-Stereoselective Monoalkylation of β,β-Dichlorostyrenes by Photoredox/Nickel Dual Catalysis », Synlett, janv. 2021.
    Résumé : <p>Metal-catalyzed alkylation of 1,1-dihalovinyl moiety commonly suffers from both a lack of stereoselectivity and the overreaction leading to the dialkylation product. The methodology described herein features a new pathway to alkylate stereoselectively β,β-dichlorostyryl substrates to provide the <i>Z</i>-trisubstituted olefin only with fair to good yields. This cross-coupling reaction bears on the smooth and photoinduced formation of a C-centered radical that engages in a nickel-catalyzed organometallic cycle to form the key C<sub>sp2</sub>–C<sub>sp3</sub> bond.</p>
    Mots-clés : MACO.
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  • M. Balas, S. Beaudoin, A. Proust, F. Launay, et R. Villanneau, « Advantages of Covalent Immobilization of Metal-Salophen on Amino-Functionalized Mesoporous Silica in Terms of Recycling and Catalytic Activity for CO2 Cycloaddition onto Epoxides », European Journal of Inorganic Chemistry, vol. 2021, nᵒ 16, p. 1581-1591, 2021.
    Résumé : NiII and MnIII Schiff base complexes (Salophen-Ni and Salophen-MnCl) bearing a pending carboxylic group were prepared and characterized. Both complexes were grafted onto a mesoporous amino-functionalized SBA-15 silica, by formation of an amide function between the propylamine groups of the support and the carboxylic acid functions of the salophen ligand (corresponding respective to 1.30 wt.% of Ni and 1.06 wt.% of Mn). The co-catalytic behaviour of the free and grafted complexes was then evaluated in the CO2 cycloaddition reaction onto styrene oxide, using tetra-butylammonium bromide (n−Bu4NBr) as the main catalyst. In homogeneous conditions, the MnIII Schiff base complex and the NiII one, to a lesser extent, behave as efficient co-catalysts for this reaction (styrene conversion of 100 % and 65 % respectively after 3 h at 120 °C, under 15 bars of CO2). Upon immobilization at the surface of the amino-functionalized SBA-15, we showed that the co-catalytic activity of the less efficient one, i. e. Ni2+ salophen complex, could be enhanced (reaching a full conversion after 7 h), hence highlighting a potential synergistic effect between the unused amine functions of the support and the Ni2+ salophen co-catalyst. Both salophen complexes were successfully re-used in homogeneous conditions or after their immobilization without any appreciable loss of activity. This work is only a first step towards a completely heterogeneous catalytic system, in which the tetraalkylammonium halide catalyst and the metal-salophen co-catalyst will both be covalently anchored on the same support.
    Mots-clés : CO2 valorization, Cyloaddition, E-POM, Hybrid catalysts, Mesoporous materials, POLE 2, Salen derivatives.
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  • M. Balas, L. K/Bidi, F. Launay, et R. Villanneau, « Chromium-Salophen as a Soluble or Silica-Supported Co-Catalyst for the Fixation of CO2 Onto Styrene Oxide at Low Temperatures », Frontiers in Chemistry, vol. 9, p. 765108, oct. 2021.
    Résumé : Addition of a soluble or a supported Cr III -salophen complex as a co-catalyst greatly enhances the catalytic activity of Bu 4 NBr for the formation of styrene carbonate from styrene epoxide and CO 2 . Their combination with a very low co-catalyst:Bu 4 NBr:styrene oxide molar ratio = 1:2:112 (corresponding to 0.9 mol% of Cr III co-catalyst) led to an almost complete conversion of styrene oxide after 7 h at 80°C under an initial pressure of CO 2 of 11 bar and to a selectivity in styrene carbonate of 100%. The covalent heterogenization of the complex was achieved through the formation of an amide bond with a functionalized {NH 2 }-SBA-15 silica support. In both conditions, the use of these Cr III catalysts allowed excellent conversion of styrene already at 50°C (69 and 47% after 24 h, respectively, in homogeneous and heterogeneous conditions). Comparison with our previous work using other metal cations from the transition metals particularly highlights the preponderant effect of the nature of the metal cation as a co-catalyst in this reaction, that may be linked to its calculated binding energy to the epoxides. Both co-catalysts were successfully reused four times without any appreciable loss of performance.
    Mots-clés : E-POM, POLE 2.

  • A. Benchohra, Y. Li, L. - M. Chamoreau, B. Baptiste, E. Elkaïm, N. Guillou, D. Kreher, et R. Lescouëzec, « The Atypical Hysteresis of [Fe(C6F5Tp)2]: Overlay of Spin-Crossovers and Symmetry-Breaking Phase Transition », Angewandte Chemie, vol. 133, nᵒ 16, p. 8885-8889, 2021.
    Résumé : The [FeII(C6F5Tp)2] spin-crossover complex is an atypical molecular switch, which can be converted upon annealing between two archetypal spin-crossover behaviours: from an extremely gradual spin-crossover to a broad hysteretic spin-transition (of ca. 65 K). The hysteresis shows an uncommon “rounded shape” that is reproducible upon cycling temperature. In depth structural studies reveal a first crystal phase transition, which occurs upon melting and recrystallizing at high temperature. This first irreversible transition is associated with a radical change in the crystal packing. More importantly, the “rounded and broad” hysteretic transition is shown to occur in a non-cooperative SCO system and is associated with the occurrence of a symmetry-breaking phase transition that appears when roughly ca. 50 % of the SCO complexes are switched.
    Mots-clés : ERMMES, POLE 2.

  • S. Boujday et M. Salmain, « Nanoparticules d’or pour les biocapteurs : lecture optique de la reconnaissance moléculaire », Photoniques, nᵒ 106, p. 39-43, janv. 2021.
    Résumé : Les propriétés extraordinaires des nanoparticules d’or et/ou d’argent en ont fait des objets courtisés par les scientifiques toutes disciplines confondues. L’intensité de leur couleur ainsi que leur grande sensibilité optique au milieu environnant en font de puissants transducteurs pour les biocapteurs ; que ce soit grâce à des spectrophotomètres ou simplement par observation à l’oeil nu. Elles assurent la lecture de la reconnaissance moléculaire via des scénarios variés alliant simplicité et faible coût.
    Mots-clés : CHEMBIO, POLE 3.

  • F. Carlet, G. Bertarini, G. Broggini, A. Pradal, et G. Poli, « Oxoammonium-Mediated Allylsilane–Ether Coupling Reaction », European Journal of Organic Chemistry, vol. 2021, nᵒ 15, p. 2162-2168, 2021.
    Résumé : A new C(sp3)−H functionalization reaction consisting of the oxidative α-allylation of allyl- and benzyl- methyl ethers has been developed. The C−C coupling could be carried out under mild conditions thanks to the use of cheap and green oxoammonium salts. The scope of the reaction was studied over 27 examples, considering the nature of the substituents on the two coupling partners.
    Mots-clés : Allylation, Benzyl ethers, C(sp3)−H functionalization, Cinnamyl ethers, Oxoammonium, ROCS.

  • L. Chang, N. Fischer-Durand, G. Gontard, B. Bertrand, S. Thorimbert, et L. Dechoux, « A solvent-free, catalyst-free formal [3+3] cycloaddition dearomatization strategy: towards new fluorophores for biomolecules labelling », ChemSusChem, vol. n/a, nᵒ n/a, 2021.
    Résumé : A general, sustainable dearomatization reaction for nitrogen-containing heterocycles was developed. Under solvent free conditions and without catalyst, the biorenewable methyl coumalate ( MC ) reacts as an efficient C3 partner to convert eleven types of basic aromatic rings into their pyrido[1,2-a] fused derivatives in good to excellent yields. The fluorescence properties of some of the products were harnessed to conjugate fluorescent tags to BSA and immunoglobulin G.
    Mots-clés : CHEMBIO, dearomatization reaction, fluorescent probes, methyl coumalate, Michael addition, Nitrogen heterocycles, POLE 3.
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  • F. Chemla et A

    . Perez-Luna, « 2.5 Radical–Polar Crossover Reactions », in Free Radicals: Fundamentals and Applications in Organic Synthesis 2, 2021ᵉʳ éd., Thieme Verlag, 2021.
    Résumé : Radical–polar crossover reactions, that is, single-electron redox events allowing for the interconversion between radical and ionic intermediates, make it possible to connect radical and polar processes in the same synthetic transformation. Such a combination is the basis of much original synthetic methodology, which is particularly useful in the context of domino, tandem, or multicomponent reactions. This chapter comprehensively covers the field of radical–polar crossover reactions, with a primary emphasis on transformations wherein both the radical and polar processes provide synthetic elaboration.
    Mots-clés : Organic Chemistry, POLE 1, ROCS.
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  • S. Curpanen, G. Poli, J. Oble, et A. Perez‐Luna, « C(sp2)−Si Bond Functionalization through Intramolecular Activation by Alkoxides », European Journal of Organic Chemistry, vol. 2021, nᵒ 7, p. 1055-1071, 2021.
    Résumé : Organosilicon reagents are invaluable tools in the hands of the modern chemist that allow accomplishing a number of synthetically useful transformations. While some are standard reactions, others are more complex transformations, such as the Brook rearrangement and its variants. This carbon-to-oxygen silyl migration represents a privileged method to generate transient carbanionic species well suited to undergo functionalization upon electrophilic substitution in the presence of an electrophile. This minireview focuses on recent advances in C(sp2)−Si bond functionalization through intramolecular activation by alkoxides. The key elements of reactivity will be highlighted in the introduction to allow the proper understanding of the migration process. Then, an overview of the reactivity of substrates incorporating the C(sp2)−Si motif and their synthetic applications will be provided.
    Mots-clés : Anion Relay Chemistry, Brook rearrangement, Hiyama cross-coupling, POLE 1, ROCS, Silyl migration, Synthetic methods.
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  • K. de la Vega-Hernández, F. Chemla, F. Ferreira, O. Jackowski, et A. Perez-Luna, « Radical Germylzincation of Aryl- and Alkyl-Substituted Internal Alkynes », Organic Letters, vol. 23, nᵒ 11, p. 4426-4430, juin 2021.
    Résumé : The stereoselective germylzincation of internal alkynes delivering trisubstituted vinylgermanes is achieved via a radical chain process involving Ph3GeH and Et2Zn with AIBN as the initiator. Excellent levels of regiocontrol are observed for nonsymmetric (aryl, alkyl)-substituted alkynes and for propargylic alcohols with aryl-, alkyl-, or silyl-substituted alkynes. The germylzincation reaction can be combined in one pot with the Cu(I)-mediated electrophilic substitution of the C(sp2)–Zn bond to obtain synthetically challenging tetrasubstituted vinylgermanes.
    Mots-clés : POLE 1, ROCS.

  • H. Dossmann, L. Fontaine, T. Weisgerber, V. Bonnet, E. Monflier, A. Ponchel, et C. Przybylski, « First Steps to Rationalize Host–Guest Interaction between α-, β-, and γ-Cyclodextrin and Divalent First-Row Transition and Post-transition Metals (Subgroups VIIB, VIIIB, and IIB) », Inorganic Chemistry, vol. 60, nᵒ 2, p. 930-943, janv. 2021.
    Mots-clés : CSOB, Cyclodextrin, POLE 3.

  • Y. Fu, Y. Ding, L. Zhang, Y. Zhang, J. Liu, et P. Yu, « Poly ethylene glycol (PEG)-Related controllable and sustainable antidiabetic drug delivery systems », European Journal of Medicinal Chemistry, vol. 217, p. 113372, 2021.

  • D. Gatineau, H. Dossmann, H. Clavier, A. Memboeuf, L. Drahos, Y. Gimbert, et D. Lesage, « Ligand effects in gold-carbonyl complexes: evaluation of the bond dissociation energies using blackbody infrared radiative dissociation », International Journal of Mass Spectrometry, p. 116545, févr. 2021.

  • A. Gillet, S. Cher, M. Tassé, T. Blon, S. Alves, G. Izzet, B. Chaudret, A. Proust, P. Demont, F. Volatron, et S. Tricard, « Polarizability is a key parameter for molecular electronics », Nanoscale Horizons, vol. 6, nᵒ 3, p. 271-276, mars 2021.
    Résumé : Identifying descriptors that govern charge transport in molecular electronics is of prime importance for the elaboration of devices. The effects of molecule characteristics, such as size, bulkiness or charge, have been widely reported. Herein, we show that the molecule polarizability can be a crucial parameter to consider. To this end, platinum nanoparticle self-assemblies (PtNP SAs) are synthesized in solution, including a series of polyoxometalates (POMs). The charge of the POM unit can be modified according to the nature of the central heteroatom while keeping its size constant. POM hybrids that display remote terminal thiol functions strongly anchor the PtNP surface to form robust SAs. IV curves, recorded by conductive AFM, show a decrease in Coulomb blockade as the dielectric constant of the POMs increases. In this system, charge transport across molecular junctions can be interpreted as variations in polarizability, which is directly related to the dielectric constant.
    Mots-clés : E-POM, POLE 2.
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  • A. Harbi, Y. L. Godec, Y. Li, H. Moutaabbid, S. Benmokhtar, et M. Moutaabbid, « Experimental and theoretical investigation of the electronic, magnetic, and optical properties of a new oxyphosphate, Ni0.25Mn0.25TiO(PO4) », Journal of Physics and Chemistry of Solids, vol. 148, p. 109633, 2021.
    Résumé : The structural, magnetic, and optical properties of a new oxyphosphate, Ni0.25Mn0.25TiOPO4, have been investigated by X-ray diffraction (XRD) analysis, magnetic FC-ZFC measurements, and vibrational spectroscopy (Raman, IR, WDS, and UV/visible). XRD analysis showed that the compound crystallizes in a monoclinic structure, space group P21/c, with unit cell parameters of a = 7.3758(2) Å, b = 7.3255(2) Å, c = 7.3448(2) Å, and β = 120.25(2)°. Elemental analysis of the powder confirmed the presence of Ni, Mn, Ti, and P therein. Raman and IR spectra show strong bands at 749 and 787 cm−1, respectively, attributable to the vibration of –Ti–O–Ti–O– bonds in infinite chains. Magnetic studies have been performed in the temperature range from 2 to 300 K. The results revealed a weak antiferromagnetic coupling between spins in Ni0.25Mn0.25TiOPO4. The band-gap energy was estimated as Eg = 1.99 eV based on UV/Vis spectrophotometry. To better understand the experimental data, density functional theory (DFT) computations were performed within the generalized gradient approximation (GGA) and GGA + U. The partial density of states (PDOS) shows strong hybridization between O 2p, Mn 3d, and Ni 3d in the valence band and between Mn 3d, Ni 3d, and Ti 3d in the conduction band.
    Mots-clés : ERMMES, POLE 2.

  • X. He, Y. Nie, M. Zhong, S. Li, X. Li, Y. Guo, Z. Liu, Y. Gao, F. Ding, D. Wen, et Y. Zhang, « New organoselenides (NSAIDs-Se derivatives) as potential anticancer agents: Synthesis, biological evaluation and in silico calculations », European Journal of Medicinal Chemistry, vol. 218, p. 113384, 2021.

  • S. C. L. Kamerlin, D. J. Allen, B. de Bruin, E. Derat, et H. Urdal, « Journal Open Access and Plan S: Solving Problems or Shifting Burdens? », Development and Change, vol. n/a, nᵒ n/a, 2021.
    Résumé : This academic thought piece provides an overview of the history of, and current trends in, publishing practices in the scientific fields known to the authors (chemical sciences, social sciences and humanities), as well as a discussion of how open access mandates such as Plan S from cOAlition S will affect these practices. It begins by summarizing the evolution of scientific publishing, in particular how it was shaped by the learned societies, and highlights how important quality assurance and scientific management mechanisms are being challenged by the recent introduction of ever more stringent open access mandates. The authors then discuss the various reactions of the researcher community to the introduction of Plan S, and elucidate a number of concerns: that it will push researchers towards a pay-to-publish system which will inevitably create new divisions between those who can afford to get their research published and those who cannot; that it will disrupt collaboration between researchers on the different sides of cOAlition S funding; and that it will have an impact on academic freedom of research and publishing. The authors analyse the dissemination of, and responses to, an open letter distributed and signed in reaction to the introduction of Plan S, before concluding with some thoughts on the potential for evolution of open access in scientific publishing.
    Mots-clés : MACO.
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  • S. Khodjoyan, E. Remadna, H. Dossmann, D. Lesage, G. Gontard, J. Forté, H. Hoffmeister, U. Basu, I. Ott, P. Spence, Z. Waller, M. Salmain, et B. Bertrand, « [(C^C)Au(N^N)]+ complexes as a new family of anticancer candidates: synthesis, characterization and exploration of the antiproliferative properties », Chemistry – A European Journal, vol. n/a, nᵒ n/a, 2021.
    Résumé : A library of eleven cationic gold(III) complexes of the general formula [(C^C)Au(N^N)] + when C^C is either biphenyl or 4,4’-ditertbutyldiphenyl and N^N is a bipyridine, phenanthroline or dipyridylamine derivative have been synthesized and characterized. Contrasting effects on the viability of the triple negative breast cancer cells MDA-MB-231 was observed from a preliminary screening. The antiproliferative activity of the seven most active complexes were further assayed on a larger panel of human cancer cells as well as on non-cancerous cells for comparison. Two complexes stood out for being either highly active or highly selective. Eventually, reactivity studies with biologically meaningful amino acids, glutathione, higher order DNA structures and thioredoxin reductase (TrxR) revealed a markedly different behavior from that of the well-known coordinatively isomeric [(C^N^C)Au(NHC)] + structure. This makes the [(C^C)Au(N^N)] + complexes a new class of organogold compounds with an original mode of action.
    Mots-clés : Bioorganometallics, Biphenyl, Cancer, Chelate, CHEMBIO, CSOB, Gold, POLE 3.

  • G. Lemière, A. Millanvois, C. Ollivier, et L. Fensterbank, « A Parisian Vision of the Chemistry of Hypercoordinated Silicon Derivatives », The Chemical Record, vol. 21, nᵒ 5, p. 1119-1129, 2021.
    Résumé : Less than ten years of acquaintance with hypercoordinated silicon derivatives in our lab is described in this account. Martin's spirosilane derivatives open new opportunities as ligands and as agents for the activation of small molecules and bis-catecholato silicates have proven to be exquisite radical precursors in photoredox conditions for broad synthetic applications.
    Mots-clés : Lewis acid, MACO, photoredox, radical, silicate, Silicon.
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  • A. Lepoetre, S. Ognier, M. Zhang, J. Wengler, S. Al Ayoubi, C. Ollivier, L. Fensterbank, X. Duten, et M. Tatoulian, « Amination of Cyclohexane by Dielectric Barrier Discharge Processing in a Continuous Flow Microreactor: Experimental and Simulation Studies », Plasma Chemistry and Plasma Processing, vol. 41, nᵒ 1, p. 351-368, 2021.
    Résumé : A miniaturized flow device has been developed to combine microfluidics technology and plasma process. In this microreactor, atmospheric pressure dielectric barrier discharges are generated in a gas in contact with a liquid phase. This study was conducted with plasma generated in ammonia in contact with a flow of liquid cyclohexane. Cyclohexylamine was synthesized with a good selectivity, and the process can be implemented to improve conversion and effectiveness. Numerical simulations confirmed that N­ H2 radicals are generated in the plasma and react with cyclohexyls radicals to achieve the reaction, giving a selectivity of 50% and a total molar conversion of 20% of cyclohexane. The effects of voltage and frequency on the selectivity and the experimental conversion rate were studied and discussed.
    Mots-clés : MACO.

  • A. Li, L. - M. Chamoreau, B. Baptiste, Y. Li, Y. Journaux, et L. Lisnard, « Solvothermal synthesis, structure and magnetic properties of heterometallic coordination polymers based on a phenolato-oxamato co-bidentate-tridentate ligand », Dalton Transactions, vol. 50, nᵒ 2, p. 681-688, janv. 2021.
    Résumé : The use of solvothermal conditions has succesfully led to the preparation of heterometallic 1D coordination polymers from a co-bidentate-tridentate phenolato-oxamato ligand. The reaction of the N-(2-hydoxyphenyl)oxamic acid (ohpma) with acetate salts of transition metal ions at 80 °C has yielded the heterobimetallic [Cu(ohpma)M(OAc)(DMF)2] (M = Co (1); Mn (2)) and the heterotrimetallic [Cu(ohpma)Co0.57Mn0.43(OAc)(DMF)2] (3) chain compounds. Single-crystal and powder diffraction studies show that the polymers are isostructural. Magnetic studies suggest the existence of an inter-chain two-dimensional antiferromagnetic interaction taking place in compounds 1–3.
    Mots-clés : ERMMES, POLE 2.

  • A. Li, L. - M. Chamoreau, B. Baptiste, Y. Li, Y. Journaux, et L. Lisnard, « Solvothermal synthesis, structure and magnetic properties of heterometallic coordination polymers based on a phenolato-oxamato co-bidentate-tridentate ligand », Dalton Transactions, vol. 50, nᵒ 2, p. 681-688, 2021.
    Résumé : First examples of 1D oxamate-based coordination polymers obtained solvothermally. , The use of solvothermal conditions has succesfully led to the preparation of heterometallic 1D coordination polymers from a co-bidentate-tridentate phenolato-oxamato ligand. The reaction of the N -(2-hydoxyphenyl)oxamic acid (ohpma) with acetate salts of transition metal ions at 80 °C has yielded the heterobimetallic [Cu(ohpma)M(OAc)(DMF) 2 ] (M = Co ( 1 ); Mn ( 2 )) and the heterotrimetallic [Cu(ohpma)Co 0.57 Mn 0.43 (OAc)(DMF) 2 ] ( 3 ) chain compounds. Single-crystal and powder diffraction studies show that the polymers are isostructural. Magnetic studies suggest the existence of an inter-chain two-dimensional antiferromagnetic interaction taking place in compounds 1–3 .

  • A. Li, J. Forté, Y. Li, Y. Journaux, et L. Lisnard, « Synthesis, structure and magnetic properties of an oxamate-based 1D coordination polymer built on pentametallic links », Inorganica Chimica Acta, vol. 521, p. 120320, juin 2021.
    Résumé : The solvothermal reaction of the hexadentate 2-(oxamato)benzoic acid ligand (oaba) with copper(II) and cobalt(II) ions has yielded the [Cu4Co3(oaba)4(OH)2(DMF)6]·2(DMF)·1H2O (1) 1D coordination polymer. The single-crystal X-ray diffraction study reveals the formation of a neutral chain built from pentametallic complexes where each multi-polydentate ligand bridges four metal centres. The atypical morphology observed here for an oxamate-based 1D polymer arises from the use of a ligand bearing extra coordination sites. Magnetometry indicates strong dominating antiferromagnetic interactions within the polymer resulting in a non-zero ferrimagnetic state at low temperature.
    Mots-clés : ERMMES, POLE 2.

  • J. Liu, X. Ding, Y. Fu, C. Xiang, Y. Yuan, Y. Zhang, et P. Yu, « Cyclodextrins based delivery systems for macro biomolecules », European Journal of Medicinal Chemistry, vol. 212, p. 113105, 2021.

  • J. Liu, B. Wang, C. Przybylski, O. Bistri‐Aslanoff, M. Ménand, Y. Zhang, et M. Sollogoub, « Programmed Synthesis of Hepta‐Differentiated β‐Cyclodextrin: 1 out of 117655 Arrangements », Angewandte Chemie International Edition, vol. 60, nᵒ 21, p. 12090-12096, mai 2021.
    Mots-clés : CSOB, GOBS, POLE 3.

  • S. Mabrouk, H. Rinnert, L. Balan, S. Blanchard, J. Jasniewski, G. Medjahdi, R. B. Chaabane, et R. Schneider, « Aqueous synthesis of highly luminescent ternary alloyed Mn-doped ZnSeS quantum dots capped with 2-mercaptopropionic acid », Journal of Alloys and Compounds, vol. 858, p. 158315, mars 2021.
    Résumé : Highly photoluminescent and water dispersible ternary alloyed Mn-doped ZnSeS and core/shell Mn:ZnSeS/ZnS quantum dots (QDs) with pure dopant emission were synthesized through a simple aqueous route using thiolactic acid (2-MPA) as a capping ligand. Transmission electron microscopy and X-ray diffraction show that Mn:ZnSeS nanocrystals are of spherical shape, with a diameter of 2.4 nm and a cubic zinc blende structure. With the overcoating of the ZnS shell, the particle size increases to 3.7 nm, which confirms the epitaxial growth of the shell on Mn:ZnSeS cores. The photoluminescence (PL) quantum yield depends on the Mn loading and reaches 22% for Mn:ZnSeS cores doped with 10% Mn and 41% after the growth of ZnS at the surface of the cores due to the effective elimination of surface-trap states. Mn:ZnSeS QDs exhibit also long PL lifetimes (up to 681 μs) indicating that the emission originates from the spin forbidden Mn2+ 4T1 → 6A1 transition. Electron paramagnetic resonance and X-ray photoelectron spectroscopy results suggest that Mn2+ ions are located at the interface of core/shell Mn:ZnSeS/ZnS QDs. Further, the stability of Mn:ZnSeS/ZnS QDs was also investigated along with their transfer in organic phase using octanethiol.
    Mots-clés : 2-Mercaptopropionic acid, Core/shell Mn:ZnSeS/ZnS, E-POM, Mn-doped ZnSeS, Photoluminescence, POLE 2, Quantum dots, Stability.

  • J. - P. Mahy, F. Avenier, W. Ghattas, R. Ricoux, et M. Salmain, « Current Applications of Artificial Metalloenzymes and Future Developments », in Enzymes for Solving Humankind's Problems: Natural and Artificial Systems in Health, Agriculture, Environment and Energy, J. J. G. Moura, I. Moura, et L. B. Maia, Éd. Cham: Springer International Publishing, 2021, p. 363-411.
    Résumé : In between traditional homogeneous metal catalysts and enzyme catalysts, a new class of hybrid catalysts named artificial metalloenzymes resulting from the controlled embedding of transition metal species (ions, synthetic inorganic or organometallic complexes) within natural, genetically-engineered or even de novo protein scaffolds currently undergoes a tremendous development at the academic level. This family of hybrid assemblies ideally combines the features of their individual components, allowing a wide range of chemical reactions, including new-to-nature reactions, to be catalyzed under mild, eco-compatible conditions with high chemo- and/or stereoselectivity. This chapter intends to summarize the most remarkable achievements in artificial metalloenzyme design and properties with emphasis put on industrially relevant chemical reactions, including oxidations, imine reductions, C–C and C–N bonds formation. It also gives an up-to-date survey on the most advanced applications of artificial metalloenzymes in cascade reactions and in vivo catalysis.
    Mots-clés : Carbene insertion, Cascade reactions, CHEMBIO, Directed evolution, In vivo catalysis, Metathesis, Oxidation, POLE 3, Polymerization, Reduction, Uncaging.

  • Y. Mazouzi, A. Miche, A. Loiseau, B. Beito, C. Méthivier, D. Knopp, M. Salmain, et S. Boujday, « Design and Analytical Performances of a Diclofenac Biosensor for Water Resources Monitoring », ACS sensors, août 2021.
    Résumé : Because the broadly consumed pain killer diclofenac (DCF) is a recognized pollutant, monitoring of its concentration is routinely performed in surface waters. As a valuable alternative to chromatographic and immunochemical assays, we developed a piezoelectric immunosensor to quantify DCF, first in buffer (PBS) and then in river water samples. A sensing layer comprising DCF was built up on the surface of silica-coated quartz sensors using a robust coupling chemistry. Binding of a highly affine monoclonal anti-DCF antibody was monitored in real time by quartz crystal microbalance with dissipation (QCM-D) measurements from which were determined a dissociation constant KD of 0.24 nM and an acoustic antibody surface coverage of 1120 ng/cm2 at saturation. On the other hand, an optical antibody surface coverage of 260 ng/cm2 was determined by combined nanoplasmonic sensing measurement, giving a hydration percentage of 75% for the antibody monolayer. DCF assay was further set up following a competitive format for which binding of antibody to the sensing layer is inhibited by DCF in solution. The piezoelectric sensor response expressed as frequency shift ΔF was inversely related to the concentration of DCF with a dynamic range of 15-46 nM and a limit of detection (LoD) of 9.5 nM (2.8 μg/L) in PBS. This piezoelectric immunosensor was eventually applied to the assay of DCF in surface water samples taken at three different locations in the Seine and Marne rivers. The calculated concentration of DCF in these samples was in good agreement with official data published by the French center of water analysis eaufrance.
    Mots-clés : antibody, CHEMBIO, immunosensor, nanoplasmonics, nonsteroidal anti-inflammatory drug, POLE 3, quartz crystal microbalance.

  • C. Medena, C. Aubert, E. Derat, L. Fensterbank, G. Gontard, O. Khaled, C. Ollivier, N. Vanthuyne, M. Petit, et M. Barbazanges, « Helical Bisphosphinites in Asymmetric Tsuji-Trost Allylation: a Remarkable P:Pd Ratio Effect », ChemCatChem, vol. 13, nᵒ 21, p. 4543-4548, 2021.
    Résumé : This article discloses a study on a chiral bis-phosphorylated-helical ligand in the palladium-catalyzed Tsuji-Trost allylation. The use of 2,15-bisphosphinite-[6]-helicenes revealed a remarkable ligand effect, in which the (R) and (S) isomeric products can be selectively formed as a direct function of the amount of ligand introduced. Investigation of the organometallic species involved through 31P NMR spectroscopic analysis of a model complex and X-Ray diffraction analysis together with DFT calculations shed light on this phenomenon.
    Mots-clés : chirality, helicene, homogeneous catalysis, MACO, phosphinite, POLE 1, Tsuji-Trost allylation.

  • G. Mellot, J. - M. Guigner, J. Jestin, L. Bouteiller, F. Stoffelbach, et J. Rieger, « Unexpected thermo-responsiveness of bisurea-functionalized hydrophilic polymers in water », Journal of Colloid and Interface Science, vol. 581, p. 874-883, janv. 2021.
    Résumé : Hypothesis Thermoresponsive polymers are important materials for various applications. However, the number of polymers that exhibit this property in the temperature range of interest remains limited. The development of novel rational design strategies through the understanding of the thermal transition’s origin is therefore of utmost importance. Experiments Bisurea-functionalized water-soluble polymers were synthesized by RAFT polymerization. After direct dissolution in water, the supramolecular assemblies were analyzed by cryo-TEM and SANS. Their temperature-dependent water-solubility was characterized by various techniques, namely DLS, SANS, DSC, IR, to understand the origin of the temperature sensitivity. Findings The supramolecular assemblies exhibit an unexpected temperature-dependent solubility. For instance, a cloud point of only 39 °C was measured for poly(N,N-dimethylacrylamide) assemblies. This property is not restricted to one specific polymer but is rather a general feature of bisurea-functionalized polymers that form supramacromolecular bottlebrushes in water. The results highlight the existence of two distinct transitions; the first one is a visually perceptible cloud point due to the aggregation of individual micelles, presumably driven by the hydrophobic effect. The second transition is related to the dissociation of intermolecular bisurea hydrogen bonds. Finally, we show that it is possible to widely tune the cloud point temperature through the formation of co-assemblies.
    Mots-clés : Bisurea, Cloud point, Cylindrical micelles, Hydrogen bonding, LCST, nano-DSC, POLE 4, POLYMERES, Supramacromolecular assemblies, Supramolecular bottlebrushes, Thermoresponsive.

  • G. Passos Gomes, G. Xu, X. Zhu, L. ‐M. Chamoreau, Y. Zhang, O. Bistri‐Aslanoff, S. Roland, I. V. Alabugin, et M. Sollogoub, « Mapping C−H⋅⋅⋅M Interactions in Confined Spaces: (α‐ICyD <sup>Me</sup> )Au, Ag, Cu Complexes Reveal “Contra‐electrostatic H Bonds” Masquerading as Anagostic Interactions** », Chemistry – A European Journal, p. chem.202100263, mai 2021.

  • V. Pellas, J. Blanchard, C. Guibert, J. - M. Krafft, A. Miche, M. Salmain, et S. Boujday, « Gold Nanorod Coating with Silica Shells Having Controlled Thickness and Oriented Porosity: Tailoring the Shells for Biosensing », ACS Applied Nano Materials, août 2021.
    Résumé : The coating of gold nanorods with a silica shell (AuNR@SiO2) is an effective way to extend their use in a wide variety of biomedical applications including biosensing, drug delivery and photothermal therapy. A silica shell offers numerous advantages as it provides more stability, frees the surface from toxic cetyltrimethylammonium bromide (CTAB), and preserves the rod shape under photothermal conditions. This shell needs to be very thin for applications such as plasmonic biosensing, while a thicker and porous shell is suited for drug encapsulation and further controlled release. We introduce herein a strategy to perform silica coating based on dissociation of tetraethylorthosilicate (TEOS) hydrolysis and condensation reactions. This dissociation is achieved by a pH modulation of the reaction medium, and, depending on selected pH conditions, AuNR@SiO2 with a thick silica shell having an organized mesoporosity aligned either parallel (AuNR@//m-SiO2) or perpendicular (AuNR@⊥m-SiO2) to the AuNR surface was generated. Moreover, when mercaptopropyltrimethoxysilane (MPTMS) was used as a surface primer prior to TEOS condensation, ultrathin and homogeneous silica shells (AuNR@t-SiO2) of controllable thickness in the range 2–6 nm were produced. While formation, at high TEOS concentration, of core-free silica nanoparticles is evidenced by TEM analysis before the purification procedure, their total elimination during the purification step was achieved by addition of a suitable amount of CTAB to ensure the colloidal stability of the core-free and core–shell nanoparticles. Complete elimination of CTAB from AuNR@SiO2 was demonstrated by XPS, Raman, and ζ-potential measurements. Finally, the efficiency of AuNR@t-SiO2 in label-free plasmonic biosensing of a model target was demonstrated and their refractive index sensitivity factor was improved by 30% compared to CTAB-capped AuNRs.
    Mots-clés : CHEMBIO, POLE 3.

  • C. Przybylski et V. Bonnet, « Discrimination of isomeric trisaccharides and their relative quantification in honeys using trapped ion mobility spectrometry », Food Chemistry, vol. 341, p. 128182, 2021.

  • J. P. Rada, J. Forté, G. Gontard, C. - M. Bachelet, N. A. Rey, M. Salmain, et V. Corcé, « Novel luminescent benzopyranothiophene- and BODIPY-derived aroylhydrazonic ligands and their dicopper(II) complexes: syntheses, antiproliferative activity and cellular uptake studies », Journal of biological inorganic chemistry: JBIC: a publication of the Society of Biological Inorganic Chemistry, vol. 26, nᵒ 6, p. 675-688, sept. 2021.
    Résumé : Two novel unsymmetrical binucleating aroylhydrazonic ligands and four dicopper(II) complexes carrying fluorescent benzopyranothiophene (BPT) or boron dipyrromethene (BODIPY) entities were synthesized and fully characterized. Complex 1, derived from the BPT-containing ligand H3L1, had its crystal structure elucidated through X-ray diffraction measurements. The absorption and fluorescence profiles of all the compounds obtained were discussed. Additionally, the stability of the ligands and complexes was monitored by UV-vis spectroscopy in DMSO and biologically relevant media. All the compounds showed moderate to high cytotoxicity towards the triple negative human breast cancer cell line MDA-MB-231. BPT derivatives were the most cytotoxic, specially H3L1, reaching an IC50 value up to the nanomolar range. Finally, fluorescence microscopy imaging studies employing mitochondria- and nucleus-staining dyes showed that the BODIPY-carrying ligand H3L2 was highly cell permeant and suggested that the compound preferentially accumulates in the mitochondria.
    Mots-clés : Anticancer agents, Aroylhydrazones, Cellular uptake, CHEMBIO, Copper complexes, Cytotoxicity, POLE 3.

  • E. Rathahao-Paris, S. Alves, et A. Paris, « High-Throughput Metabolomics Using Flow Injection Analysis and Fourier Transform Ion Cyclotron Resonance Mass Spectrometry », in Metabolomics, vol. 159, New York, NY: Humana, 2021, p. 9-23.
    Résumé : The hyphenation of flow injection analysis (FIA) with Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) is an efficient approach usable to perform high throughput and very high resolution metabolomic data acquisition. Instrumental and analytical conditions for performing FIA-MS are provided. The procedure to optimize dilution factor of biological samples as well as to evaluate quality of acquisition data are also described. In this protocol, urine is chosen as a matrix example to illustrate the application of procedures. Last, some indications on an adapted data processing are given.
    Mots-clés : CSOB, POLE 3.

  • E. Romain, K. de la Vega-Hernández, F. Guégan, J. S. García, C. Fopp, F. Chemla, F. Ferreira, H. Gerard, O. Jackowski, S. Halbert, M. Oestreich, et A. Perez-Luna, « Development of a Radical Silylzincation of (Het)Aryl-Substituted Alkynes and Computational Insights into the Origin of the trans-Stereoselectivity », Advanced Synthesis & Catalysis, vol. 363, nᵒ 10, p. 2634-2647, 2021.
    Résumé : Aryl- and hetaryl-substituted acetylenes undergo regio- and stereoselective silylzincation by reaction with [(Me3Si)3Si]2Zn in the presence of Et2Zn (10–110 mol%) as additive. The distinctive feature of this addition across the C−C triple bond is its trans stereoselectivity. The radical nature of the silylzincation process is supported by diagnostic experiments and DFT calculations, which also corroborate the role played by steric effects to obtain that stereoselectivity. The procedure can be combined in one-pot with the copper(I)-mediated electrophilic substitution of the C(sp2)−Zn bond, with retention of the double bond geometry. This makes it valuable for the synthesis of stereodefined di- and trisubstituted vinylsilanes.
    Mots-clés : POLE 1, Radical reactions, ROCS, Silylmetalation, Silylzinc reagents, Vinylsilanes, Zinc.
    Pièce jointe Full Text PDF 5.6 Mo (source)

  • S. Topin-Ruiz, A. Mellinger, E. Lepeltier, C. Bourreau, J. Fouillet, J. Riou, G. Jaouen, L. Martin, C. Passirani, et N. Clere, « p722 ferrocifen loaded lipid nanocapsules improve survival of murine xenografted-melanoma via a potentiation of apoptosis and an activation of CD8+ T lymphocytes », International Journal of Pharmaceutics, p. 120111, janv. 2021.
    Résumé : Metastatic melanoma is a malignant tumor with a poor prognosis. Recent new therapeutics improved the survival of patients at a metastatic stage. However, the low response rate to immunotherapy, explained in part by resistance to apoptosis, needs to develop new strategies. The ferrocifen family represents promising bioorganometallic molecules for melanoma treatment since they show potent anticancer properties. The aim of this study is (i) to evaluate the benefits of a strategy involving encapsulated p722 in lipid nanocapsules (LNC) in B16F10 melanoma mice models and (ii) to compare the beneficial effects with an existing therapy such as anti-CTLA4 mAb. Interestingly, LNC-p722 induces a significant decrease of melanoma cell viability. In vivo data shows a significant improvement in the survival rate and a slower tumor growth with p722-loaded LNC in comparison with anti-CTLA4 mAb. Western blots confirm that LNC-p722 potentiates intrinsic apoptotic pathway. Treatment with LNC-p722 significantly activates CD8+ T lymphocytes compared to treatment with anti-CTLA4 mAb. This study uncovers a new therapeutic strategy with encapsulated p722 to prevent B16F10 melanoma growth and to improve survival of treated mice.
    Mots-clés : apoptosis, CD8 T lymphocytes, CHEMBIO, Ferrocifen, metastatic melanoma, POLE 3.

  • A. Vessières, E. Quissac, N. Lemaire, A. Alentorn, P. Domeracka, P. Pigeon, M. Sanson, A. Idbaih, et M. Verreault, « Heterogeneity of Response to Iron-Based Metallodrugs in Glioblastoma Is Associated with Differences in Chemical Structures and Driven by FAS Expression Dynamics and Transcriptomic Subtypes », International Journal of Molecular Sciences, vol. 22, nᵒ 19, p. 10404, janv. 2021.
    Résumé : Glioblastoma (GBM) is the most frequent and deadliest primary brain cancer in adults, justifying the search for new treatments. Some members of the iron-based ferrocifen family have demonstrated a high cytotoxic effect on various cancer cell lines via innovative mechanisms of action. Here, we evaluated the antiproliferative activity by wst-1 assay of six ferrocifens in 15 molecularly diverse GBM patient-derived cell lines (PDCLs). In five out of six compounds, the half maximal inhibitory concentration (IC50) values varied significantly (10 nM &lt; IC50 &lt; 29.8 µM) while the remaining one (the tamoxifen-like complex) was highly cytotoxic against all PDCLs (mean IC50 = 1.28 µM). The pattern of response was comparable for the four ferrocifens bearing at least one phenol group and differed widely from those of the tamoxifen-like complex and the complex with no phenol group. An RNA sequencing differential analysis showed that response to the diphenol ferrocifen relied on the activation of the Death Receptor signaling pathway and the modulation of FAS expression. Response to this complex was greater in PDCLs from the Mesenchymal or Proneural transcriptomic subtypes compared to the ones from the Classical subtype. These results provide new information on the mechanisms of action of ferrocifens and highlight a broader diversity of behavior than previously suspected among members of this family. They also support the case for a molecular-based personalized approach to future use of ferrocifens in the treatment of GBM.
    Mots-clés : biomarkers, bioorganometallic chemistry, CHEMBIO, death receptor signaling pathway, ferrocene, personalized medicine, POLE 3, targeted therapy.

  • A. Vessières, Y. Wang, M. J. McGlinchey, et G. Jaouen, « Multifaceted chemical behaviour of metallocene (M = Fe, Os) quinone methides. Their contribution to biology », Coordination Chemistry Reviews, vol. 430, p. 213658, 2021.

  • Q. P. Xuan, J. Glatz, A. Benchohra, J. - R. Jiménez, R. Plamont, L. - M. Chamoreau, A. Flambard, Y. Li, L. Lisnard, D. Dambournet, O. J. Borkiewicz, M. - L. Boillot, L. Catala, A. Tissot, et R. Lescouëzec, « Building responsive materials by assembling {Fe4Co4} switchable molecular cubes », Journal of Materials Chemistry C, vol. 9, nᵒ 28, p. 8882-8890, juill. 2021.
    Résumé : Responsive materials that can answer to chemical or physical external stimuli offer numerous prospects in material science. Here, we have elaborated a two-step synthetic approach that allows incorporating molecular cubic switches into a polymeric material. Firstly, a preformed half-capped, Cs+-templated {Fe4Co4} cyanido-polymetallic cubic unit (“pro-cube”) is obtained and proven to be stable in solution, as demonstrated by paramagnetic NMR. Secondly, the reaction of the pro-cube with a ditopic scorpionate ligand enables the precipitation of a polymeric network containing the cubic unit. Furthermore, the adequately chosen ditopic ligand that coordinates the Co ions of the pro-cube allows us to preserve the switchable properties of the cubic unit. Indeed, the magnetic properties of the polymeric material compare well with those of the molecular cubic model that is obtained by reacting a non-bridging scorpionate ligand, and that was prepared as a reference. Both the polymeric material and the molecular model cube show a thermally-induced metal–metal electron transfer near room temperature. Interestingly, the magnetic state of the polymeric material is shown to depend on its hydration state, indicating its capability to act as a chemo-sensor.
    Mots-clés : ERMMES, POLE 2.

  • L. Zhang, M. - A. Arrio, S. Mazerat, L. Catala, W. Li, E. Otero, P. Ohresser, L. Lisnard, C. Cartier dit Moulin, T. Mallah, et P. Sainctavit, « Magnetic Hysteresis in a Monolayer of Oriented 6 nm CsNiCr Prussian Blue Analogue Nanocrystals », Inorganic Chemistry, vol. 60, nᵒ 21, p. 16388-16396, nov. 2021.
    Résumé : Prussian blue analogue nanocrystals of the CsINiII[CrIII(CN)6] cubic network with 6 nm size were assembled as a single monolayer on highly organized pyrolytic graphite (HOPG). X-ray magnetic circular dichroism (XMCD) studies, at the Ni and Cr L2,3 edges, reveal the presence of an easy plane of magnetization evidenced by an opening of the magnetic hysteresis loop (coercive field of ≈200 Oe) when the magnetic field, B, is at 60° relative to the normal to the substrate. The angular dependence of the X-ray natural linear dichroism (XNLD) reveals both an orientation of the nanocrystals on the substrate and an anisotropy of the electronic cloud of the NiII and CrIII coordination sphere species belonging to the nanocrystals’ surface. Ligand field multiplet (LFM) calculations that reproduce the experimental data are consistent with an elongated tetragonal distortion of surface NiII coordination sphere responsible for the magnetic behavior of monolayer.
    Mots-clés : ERMMES, POLE 2.

  • T. Zhang, A. Solé‐Daura, H. Fouilloux, J. M. Poblet, A. Proust, J. J. Carbó, et G. Guillemot, « Reaction Pathway Discrimination in Alkene Oxidation Reactions by Designed Ti-Siloxy-Polyoxometalates », ChemCatChem, vol. 13, nᵒ 4, p. 1220-1229, 2021.
    Résumé : Titanium complexes of silanol functionalized polyoxometalates (THA)3[SbW9O33(RSiO)3Ti(OiPr)] (Ti-SiloxPOMs) catalyze alkene oxidation with tert-butyl hydrogen peroxide (TBHP). However catalytic activity and product distribution in the oxidation of allylic alcohols are shown to depend on the steric surrounding generated by the SiloxPOM (R=tBu, iPr, nPr). Combined experimental and computational studies clarify how steric repulsions between the oxidant (tBu group) and the surrounding SiloxPOM govern the reaction pathways leading either to oxidation of the alcohol function (R=tBu) or to alkene epoxidation (R=nPr). Moreover, another consequence of this steric repulsive interactions is that outer-sphere mechanisms become competitive with the inner-sphere ones (coordination of allylic alcohol), whether for the oxidative dehydrogenation reaction or for the epoxidation reaction. In the case of unfunctionalized olefins (linear and cyclic), we show that reducing the bulkiness surrounding the active site leads to higher conversion to epoxide, emphasizing that these Ti-SiloxPOMs may behave as structural and functional models for metal single-site in Ti-Silicates.
    Mots-clés : alkene, DFT, E-POM, mechanistic study, oxidation, POLE 2, polyoxotungstates, titanium.


  • Abdmouleh, Fatma, El Arbi, Mehdi, Hajer, Ben Saad, Jellali, Karim, Etata, Emna, Amara, Ibtissem Ben, Pigeon, Pascal, Hanen, Ben Hassen, Top, Siden, Jaouen, Gérard, Hammami, Riadh, Mamdouh, Ben Ali, et Gupta, Girish Kumar, « Antimicrobial, Antitumor and Side Effects Assessment of a Newly Synthesized Tamoxifen Analog », Current Topics in Medicinal Chemistry, vol. 20, nᵒ 25, p. 2281-2288, sept. 2020.
    Résumé : Background: Tamoxifen citrate is a very prevalent drug marketed under several trade names like Apo-Tamox, Nolvadex, Tamec, Tamizam, and Tamoplex. This molecule is approved by the FDA for breast cancer treatment. Some studies have shown that tamoxifen has anti-tuberculosis and antiparasitic activities. Like any drug, tamoxifen possesses side effects, more or less dangerous. Aims: Basically, this work is a comparative study that aims to: primarily compare the antimicrobial and antitumor activities of tamoxifen and a newly synthesized tamoxifen analog; and to determine the molecule with lesser side effects. Methods: Three groups of mice were injected with tamoxifen citrate and compound 2(1,1-bis[4-(3- dimethylaminopropoxy)phenyl]-2-phenyl-but-1-ene dihydrochloride) at doses corresponding to C1 (1/10), C2 (1/50), and C3 (1/100) to compound 2 lethal dose (LD50 = 75 mg/kg) administered to adult mice. A group of noninjected mice served as a study control. Results: Experimental results suggest that compound 2 has better antitumor and antimicrobial activity than tamoxifen citrate besides its lower toxicity effects. Conclusion: The results obtained from the present study confirmed the antitumor and antimicrobial effect of tamoxifen citrate and its hematological side effects. Compound 2 seems to be more effective than tamoxifen citrate for antitumor and antimicrobial treatment while having less hematological side effects and less disruption of the blood biochemical parameters. These findings encourage us to perform further studies on compound 2 and test it for other therapeutic uses for which tamoxifen was found effective.
    Mots-clés : POLE 3.

  • S. Alves, A. Paris, et E. Rathahao-Paris, « Mass spectrometry-based metabolomics for an in-depth questioning of human health », in Advances in Clinical Chemistry, Elsevier, 2020, p. S0065242320300214.

  • N. Audureau, F. Coumes, J. - M. Guigner, T. P. T. Nguyen, C. Ménager, F. Stoffelbach, et J. Rieger, « Thermoresponsive properties of poly(acrylamide-co-acrylonitrile)-based diblock copolymers synthesized (by PISA) in water », Polymer Chemistry, vol. 11, nᵒ 37, p. 5998-6008, sept. 2020.
    Résumé : In this present work, we report the synthesis of UCST-thermoresponsive diblock copolymers using reversible addition fragmentation chain transfer (RAFT) polymerization in aqueous media. A water-soluble poly(N,N-dimethylacrylamide) macromolecular chain transfer agent (PDMAc macroRAFT) is used to promote and control the copolymerization of acrylamide and acrylonitrile in water and obtain PDMAc-b-P(AAm-co-AN) diblock copolymers. The fAN,0 and the length of the thermosensitive block (DPn) are systematically varied, in order to study their influence on the thermoresponsiveness of the block copolymers. A good blocking efficiency is generally evidenced by size exclusion chromatography. Remarkably, amphiphilic copolymer nanoparticles are formed in situ for the highest fAN,0. This is indeed the first time that such particles are produced by a polymerization-induced self-assembly (PISA) process. The morphology of the in situ formed nanoparticles and their behavior with temperature are studied by means of dynamic light scattering (DLS), (cryogenic) transmission electron microscopy ((cryo-)TEM) and turbidimetry. Spherical and worm-like nanoparticles are formed which exhibit unexpected properties, such as an unprecedented heating-induced worm-to-sphere morphological transition in water.
    Mots-clés : POLE 4, POLYMERES.
    Pièce jointe Full Text PDF 1.7 Mo (source)

  • P. Bayat, D. Lesage, et R. B. Cole, « Tutorial: Ion activation in tandem Mass spectrometry using ultra-high resolition spectroscopy », Mass Spectrometry Reviews, p. mas.21623, févr. 2020.

  • L. Bedoin, S. Alves, et J. - F. Lambert, « Origins of Life and Molecular Information: Selectivity in Mineral Surface-Induced Prebiotic Amino Acid Polymerization », ACS Earth and Space Chemistry, p. acsearthspacechem.0c00183, sept. 2020.

  • A. Beghennou, K. Passador, A. Passador, V. Corcé, S. Thorimbert, et C. Botuha, « Synthetic Strategy Studies for a Concise Access to Functionalized Pyrano[4,3-b]pyridin-7-ones: An Entry to Semi-Rigid Analogs of Antihistamines », European Journal of Organic Chemistry, vol. 2020, nᵒ 36, p. 5880-5889, sept. 2020.
    Résumé : We report short and efficient syntheses of polyfunctionalized 5,8-dihydro-7H-pyrano[4,3-b]pyridin-7-ones and 1,4-dihydro-3H-pyrano[4,3-c]pyridin-3-ones which can be considered as new aza analogs of 3-isochromanones and as promising scaffolds for medicinal chemistry. Depending on the nature of the substituent, three different and complementary synthetic methodologies were used allowing the introduction of significant diversity in the substituent on the lactone ring of the pyranopyridinones. The selective α-arylation of nitrile (SNAr) and tert-butyl ester enolate (Pd catalyzed) followed by an acidic mediated lactonisation gives access to original C8-functionalized pyrano[4,3-b]pyridin-7-ones and a seleno-mediated cyclization to C1-functionalized pyrano[4,3-c]pyridin-3-ones. We have also applied the outlined synthetic methodologies to the preparation of potential semi-rigid analogs of antihistamines.
    Mots-clés : Antihistamines, CHEMBIO, Pinner reaction, POLE 3, Pyridopyridinones, Seleno-mediated cyclization, δ-Lactone.
    Note Note
    <p>doi: 10.1002/ejoc.202001016</p>

  • Y. Ben M’Barek, T. Rosser, J. Sum, S. Blanchard, F. Volatron, G. Izzet, R. Salles, J. Fize, M. Koepf, M. Chavarot-Kerlidou, V. Artero, et A. Proust, « Dye-Sensitized Photocathodes: Boosting Photoelectrochemical Performances with Polyoxometalate Electron Transfer Mediators », ACS Applied Energy Materials, vol. 3, nᵒ 1, p. 163-169, janv. 2020.

  • A. Benchohra, C. Méthivier, J. Landoulsi, D. Kreher, et R. Lescouëzec, « Electrospray ionization: an efficient approach to deposit polymetallic molecular switches onto gold surfaces », Chemical Communications, vol. 56, nᵒ 48, p. 6587-6589, 2020.
    Résumé : Electrospray ionization (EI) deposition is proven efficient in obtaining monolayers of a polymetallic charge transfer complex on gold surfaces. , Electrospray ionization (EI) deposition is proven efficient in obtaining monolayers of a polymetallic charge transfer complex on gold surfaces. The molecule's integrity is monitored by using PM-IRRAS and XPS. This approach broadens the perspective of molecular magnetic switch deposition, which is currently dominated by the thermal evaporation of monometallic spin crossover (SCO) complexes.
    Mots-clés : ERMMES, POLE 2.
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