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  • « Quasi‐alternating polyesteramides from ε‐caprolactone and α‐amino acids ». [Online]. Available:

  • « C-2 Alkylation and Alkenylation of Indoles Catalyzed by a Low-Valent Cobalt Complex in the Absence of Reductant ». [Online]. Available:

  • M. E. Arbi, K. Jalléli, F. Trigui, P. Pigeon, M. Görmen, S. Top, S. Aifa, I. Fliss, G. Jaouen, et R. Hammami, « Efficacy of a novel ferrocenyl diaryl butene citrate compound as a biocide for preventing healthcare-associated infections », vol. 7, nᵒ 5, p. 948-954.
    Résumé : The antiseptic and disinfectant potential of a formulation containing the tamoxifen analogue 1,1-bis[4-(3-dimethylaminopropoxy)phenyl]-2-ferrocenyl-but-1-ene citrate was assessed according to European standards and pharmacopeia in comparison with a commercial antiseptic product containing hexamidine diisethionate, chlorhexidine digluconate and chlorocresol as active ingredients. The formulation met the phase 1 requirement of reducing by 5 cycles the counts of microorganisms frequently involved in healthcare-associated infections, namely Escherichia coli ATCC 10536, Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538, Enterococcus hirae ATCC 10541 and Candida albicans ATCC 10231. It also killed a clinical isolate of Acinetobacter baumannii which is highly resistant to antibiotics and antiseptics. In phase 2/step 2 tests, it reduced the counts of E. coli ATCC 10536 by 4 log cycles within 60 seconds on hands (standard EN 1499). The novel formula is a potent biocide, and this demonstration could lead to the development of a new commercial antiseptic.
    Mots-clés : CHEMBIO, POLE 3.

  • J. J. Baldoví, Y. Duan, C. Bustos, S. Cardona-Serra, P. Gouzerh, R. Villanneau, G. Gontard, J. M. Clemente-Juan, A. Gaita-Ariño, C. Giménez-Saiz, A. Proust, et E. Coronado, « Single ion magnets based on lanthanoid polyoxomolybdate complexes », Dalton Transactions, vol. 45, nᵒ 42, p. 16653 - 16660.
    Résumé : Polyoxometalate (POM) chemistry has recently offered excellent examples of single ion magnets (SIMs) and molecular spin qubits. Compared with conventional coordination compounds, POMs provide rigid and highly symmetric coordination sites. However, all POM-based SIMs reported to date exhibit a very limited range of possibilities for chemical processability. We present herein two new families of POM-based SIMs which are soluble in organic solvents: [Ln(β-Mo8O26)2]5− {LnIII = Tb, Dy, Ho, Er, Tm and Yb} and the functionalised POMs [Ln{Mo5O13(OMe)4NNC6H4-p-NO2}2]3− {LnIII = Tb, Dy, Ho, Er, Yb and Nd}. In addition, these two families represent the first SIMs based on polyoxomolybdates. A magneto-structural analysis of these families is presented, which is based on an effective crystal field model, and compared with the results reported in analogous lanthanoid SIMs based on polyoxotungstates.
    Mots-clés : EPOM, POLE 2.

  • M. Beauperin, S. Top, M. - A. Richard, D. Plażuk, P. Pigeon, S. Toma, V. Poláčková, et G. Jaouen, « The length of the bridging chain in ansa-metallocenes influences their antiproliferative activity against triple negative breast cancer cells (TNBC) », vol. 45, nᵒ 33, p. 13126-13134.
    Résumé : In order to examine whether the length of the bridging chain in ansa-ferrocenes affects their antiproliferative activity against MDA-MB-231 triple negative breast cancer cell lines (TNBC), we synthesized derivatives of the type 1-[bis-(4-hydroxyphenyl)]methylidene-[n]ferrocenophane and 1-[(4-hydroxyphenyl)-phenyl]methylidene-[n]ferrocenophane with n = 3, 4, 5. We found that the derivatives of [3]ferrocenophane, the compounds with the shortest bridging chains, are the most active. IC50 values were 0.09 ± 0.01, 2.41 ± 0.10, and 1.85 ± 0.25 μM for the dihydroxyphenyl derivatives, with n = 3, 4, 5, respectively. These differences can be explained in terms of modification of the key metabolites (radical versus quinone methides) within the ansa series depending on the length of the bridging chain. The derivative of [5]ferrocenophane, possessing two –[bis-(4-hydroxyphenyl)]methylidene groups, was also prepared. Surprisingly, this relatively large molecule is also active (IC50 = 2.7 ± 0.3 μM). Two ruthenocenophane analogs were also synthesized. These ruthenium compounds are practically inactive against MDA-MB-231 cells. The unusual chemistry of these different compounds is discussed in terms of elucidating the mechanism underlying their diverse antiproliferative activity, and their specific advantages are evaluated.
    Mots-clés : CHEMBIO, POLE 3.

  • K. Belal, S. Poitras-Jolicoeur, J. Lyskawa, G. Pembouong, G. Cooke, P. Woisel, et F. Stoffelbach, « A triple carboxylic acid-functionalized RAFT agent platform for the elaboration of well-defined telechelic 3-arm star PDMAc », vol. 52, nᵒ 9, p. 1847-1850.
    Résumé : This communication describes the synthesis of a triple acid-functionalized RAFT agent and its use to prepare well-defined 3-arm star polymers of N,N-dimethylacrylamide (DMAc). A simple esterification reaction allowed the convenient integration of three electron-rich naphthalene recognition units on the RAFT agent platform and subsequently the elaboration of a naphthalene end-decorated telechelic 3-arm star PDMAc. This functionalized star polymer was further exploited to build a hydrogel with a complementary homoditopic host unit featuring tetracationic macrocycle cyclobis(paraquat-p-phenylene) units.
    Mots-clés : POLE 4, POLYMERES.

  • V. Besse, N. Illy, G. David, S. Caillol, et B. Boutevin, « A Chitosan Derivative Containing Both Carboxylic Acid and Quaternary Ammonium Moieties for the Synthesis of Cyclic Carbonates », ChemSusChem, vol. 9, nᵒ 16, p. 2167-2173.
    Résumé : Chitosan, a renewable feedstock, is modified and used as a catalytic support in the presence of potassium iodide. The system is highly efficient towards the incorporation of carbon dioxide (CO2) into epoxides. It demonstrates very good thermal stability and is recyclable more than five times without loss of activity. The optimal reaction conditions were determined using allylglycidyl ether as a model and extended to a wide range of other epoxides. Cyclic carbonates were obtained with very high yield in a few hours under mild conditions (2–7 bar≈0.2–0.7 MPa, 80 °C) and no solvent.
    Mots-clés : chitosan, cyclic carbonates, epoxides, heterogeneous catalysis, POLE 4, POLYMERES, supported catalyst.

  • J. E. Boulicault, S. Alves, et R. B. Cole, « Negative Ion MALDI Mass Spectrometry of Polyoxometalates (POMs): Mechanism of Singly Charged Anion Formation and Chemical Properties Evaluation », Journal of The American Society for Mass Spectrometry, vol. 27, nᵒ 8, p. 1301-1313.
    Résumé : MALDI-MS has been developed for the negative ion mode analysis of polyoxometalates (POMs). Matrix optimization was performed using a variety of matrix compounds. A first group of matrixes offers MALDI mass spectra containing abundant intact singly charged anionic adduct ions, as well as abundant in-source fragmentations at elevated laser powers. A relative ranking of the ability to induce POM fragmentation is found to be: DAN > CHCA > CNA > DIT> HABA > DCTB > IAA. Matrixes of a second group provide poorer quality MALDI mass spectra without observable fragments. Sample preparation, including the testing of salt additives, was performed to optimize signals for a model POM, POMc12, the core structure of which bears four negative charges. The matrix 9-cyanoanthracene (CNA) provided the best signals corresponding to singly charged intact POMc12 anions. Decompositions of these intact anionic species were examined in detail, and it was concluded that hydrogen radical-induced mechanisms were not prevalent, but rather that the observed prompt fragments originate from transferred energy derived from initial electronic excitation of the CNA matrix. Moreover, in obtained MALDI mass spectra, clear evidence of electron transfer to analyte POM species was found: a manifestation of the POMs ability to readily capture electrons. The affinity of polyanionic POMc12 toward a variety of cations was evaluated and the following affinity ranking was established: Fe3+ > Al3+ > Li+ > Ga3+ > Co2+ > Cr3+ > Cu2+ > [Mn2+, Mg2+] > [Na+, K+]. Thus, from the available cationic species, specific adducts are preferentially formed, and evidence is given that these higher affinity POM complexes are formed in the gas phase during the early stages of plume expansion.Graphical Abstractᅟ
    Mots-clés : CSOB, POLE 3.

  • R. Breitwieser, T. Auvray, F. Volatron, C. Salzemann, A. - T. Ngo, P. - A. Albouy, A. Proust, et C. Petit, « Binary Superlattices from {Mo132} Polyoxometalates and Maghemite Nanocrystals: Long-Range Ordering and Fine-Tuning of Dipole Interactions », Small, vol. 12, nᵒ 2, p. 220-228.
    Résumé : In the present article, the successful coassembly of spherical 6.2 nm maghemite (γ-Fe2O3) nanocrystals and giant polyoxometalates (POMs) such as 2.9 nm {Mo132} is demonstrated. To do so, colloidal solutions of oleic acid-capped γ-Fe2O3 and long-chain alkylammonium-encapsulated {Mo132} dispersed in chloroform are mixed together and supported self-organized binary superlattices are obtained upon the solvent evaporation on immersed substrates. Both electronic microscopy and small angles X-ray scattering data reveal an AB-type structure and an enhanced structuration of the magnetic nanocrystals (MNCs) assembly with POMs in octahedral interstices. Therefore, {Mo132} acts as an efficient binder constituent for improving the nanocrystals ordering in 3D films. Interestingly, in the case of didodecyldimethylammonium (C12)-encapsulated POMs, the long-range ordered binary assemblies are obtained while preserving the nanocrystals magnetic properties due to weak POMs–MNCs interactions. On the other hand, POMs of larger effective diameter can be employed as spacer blocks for MNCs as shown by using {Mo132} capped with dioctadecyldimethylammonium (C18) displaying longer chains. In that case, it is shown that POMs can also be used for fine-tuning the dipolar interactions in γ-Fe2O3 nanocrystal assemblies.
    Mots-clés : binary superlattices, E-POM, EPOM, maghemites, magnetic dipolar interactions, POLE 2, Polyoxometalates, {mo132}.

  • N. Bridonneau, L. - M. Chamoreau, G. Gontard, J. - L. Cantin, J. von Bardeleben, et V. Marvaud, « A high-nuclearity metal-cyanide cluster [Mo6Cu14] with photomagnetic properties », vol. 45, nᵒ 23, p. 9412-9418.
    Résumé : A high-nuclearity metal-cyanide cluster [Mo6Cu14] has been prepared and its photomagnetic properties investigated. The photoswitchable magnetic phenomenon observed is thermally reversible (T ≈ 230 K). In the field of photomagnetism, [Mo6Cu14] represents a unique example of a nanocage and the highest nuclearity observed so far.
    Mots-clés : EPOM, POLE 2.

  • M. C. Bridoux, A. Schwarzenberg, S. Schramm, et R. B. Cole, « Combined use of direct analysis in real-time/Orbitrap mass spectrometry and micro-Raman spectroscopy for the comprehensive characterization of real explosive samples », Analytical and Bioanalytical Chemistry, vol. 408, nᵒ 21, p. 5677-5687.
    Résumé : Direct Analysis in Real Time (DART™) high-resolution Orbitrap™ mass spectrometry (HRMS) in combination with Raman microscopy was used for the detailed molecular level characterization of explosives including not only the charge but also the complex matrix of binders, plasticizers, polymers, and other possible organic additives. A total of 15 defused military weapons including grenades, mines, rockets, submunitions, and mortars were examined. Swabs and wipes were used to collect trace (residual) amounts of explosives and their organic constituents from the defused military weapons and micrometer-size explosive particles were transferred using a vacuum suction-impact collection device (vacuum impactor) from wipe and swap samples to an impaction plate made of carbon. The particles deposited on the carbon plate were then characterized using micro-Raman spectroscopy followed by DART-HRMS providing fingerprint signatures of orthogonal nature. The optical microscope of the micro-Raman spectrometer was first used to localize and characterize the explosive charge on the impaction plate which was then targeted for identification by DART-HRMS analysis in both the negative and positive modes. Raman spectra of the explosives TNT, RDX and PETN were acquired from micrometer size particles and characterized by the presence of their characteristic Raman bands obtained directly at the surface of the impaction plate nondestructively without further sample preparation. Negative mode DART-HRMS confirmed the types of charges contained in the weapons (mainly TNT, RDX, HMX, and PETN; either as individual components or as mixtures). These energetic compounds were mainly detected as deprotonated species [M–H]−, or as adduct [M + 35Cl]−, [M + 37Cl]−, or [M + NO3]− anions. Chloride adducts were promoted in the heated DART reagent gas by adding chloroform vapors to the helium stream using an “in-house” delivery method. When the polarity was switched to positive mode, DART-HRMS revealed a very complex distribution of polymeric binders (mainly polyethylene glycols and polypropylene glycols), plasticizers (e.g., dioctyl sebacate, tributyl phosphate), as well as wax-like compounds whose structural features could not be precisely assigned. In positive mode, compounds were identified either as protonated molecules or ammonium adduct species. These results clearly demonstrate the complementarity of micro-Raman microscopy combined with DART-MS. The former technique provides structural information on the type of explosives present at the surface of the sample, whereas the latter provides not only a confirmation of the nature of the explosive charge but also useful additional information regarding the nature of the complex organic matrix of binders, plasticizers, polymers, oils, and potentially other organic additives and contaminants present in the sample. Combining these two techniques provides a powerful tool for the screening, comprehensive characterization, and differentiation of particulate explosive samples for forensic sciences and homeland security applications.Graphical AbstractComprehensive characterization of explosive particles collected from swipe samples by micro-Raman and DART™-HRMS
    Mots-clés : CSOB, POLE 3.

  • X. Callies, C. Fonteneau, S. Pensec, L. Bouteiller, G. Ducouret, et C. Creton, « Adhesion and non-linear rheology of adhesives with supramolecular crosslinking points », vol. 12, nᵒ 34, p. 7174-7185.
    Résumé : Soft supramolecular materials are promising for the design of innovative and highly tunable adhesives. These materials are composed of polymer chains functionalized by strongly interacting moieties, sometimes called “stickers”. In order to systematically investigate the effect of the presence of associative groups on the debonding properties of a supramolecular adhesive, a series of supramolecular model systems has been characterized by probe-tack tests. These model materials, composed of linear and low dispersity poly(butylacrylate) chains functionalized in the middle by a single tri-urea sticker, are able to self-associate by six hydrogen bonds and range in molecular weight (Mn) between 5 and 85 kg mol−1. The linear rheology and the nanostructure of the same materials (called “PnBA3U”) were the object of a previous study. At room temperature, the association of polymers via hydrogen bonds induces the formation of rod-like aggregates structured into bundles for Mn < 40 kg mol−1 and the behavior of a soft elastic material was observed (G′ ≪ G′′ and G′ ∼ ω0). For higher Mn materials, the filaments were randomly oriented and the polymers displayed a crossover towards viscous behavior although terminal relaxation was not reached in the experimental frequency window. All these materials show, however, similar adhesive properties characterized by a cohesive mode of failure and low debonding energies (Wadh < 40 J m−2 for a debonding speed of 100 μm s−1). The debonding mechanisms observed during the adhesion tests have been investigated in detail with an Image tools analysis developed by our group. The measure of the projected area covered by cavities growing in the adhesive layer during debonding can be used to estimate the true stress in the walls of the cavities and thus to characterize the in situ large strain deformation of the thin layer during the adhesion test itself. This analysis revealed in particular that the PnBA3U materials with Mn < 40 kg mol−1 soften very markedly at large deformation like yield stress fluids, explaining the low adhesion energies measured for these viscoelastic gels.
    Mots-clés : POLE 4, POLYMERES.

  • S. Catrouillet, L. Bouteiller, O. Boyron, C. Lorthioir, E. Nicol, S. Pensec, et O. Colombani, « Patchy Supramolecular Bottle-Brushes Formed by Solution Self-Assembly of Bis(urea)s and Tris(urea)s Decorated by Two Incompatible Polymer Arms », Langmuir, vol. 32, nᵒ 35, p. 8900-8908.
    Résumé : In an attempt to design urea-based Janus nanocylinders through a supramolecular approach, nonsymmetrical bis(urea)s and tris(urea)s decorated by two incompatible polymer arms, namely, poly(styrene) (PS) and poly(isobutylene) (PIB), were synthesized using rather straightforward organic and polymer chemistry techniques. Light scattering experiments revealed that these molecules self-assembled in cyclohexane by cooperative hydrogen bonds. The extent of self-assembly was limited for the bis(urea)s. On the contrary, reasonably anisotropic 1D structures (small nanocylinders) could be obtained with the tris(urea)s (Nagg ∼ 50) which developed six cooperative hydrogen bonds per molecule. 1H transverse relaxation measurements and NOESY NMR experiments in cyclohexane revealed that perfect Janus nanocylinders with one face consisting of only PS and the other of PIB were not obtained. Nevertheless, phase segregation between the PS and PIB chains occurred to a large extent, resulting in patchy cylinders containing well separated domains of PIB and PS chains. Reasons for this behavior were proposed, paving the way to improve the proposed strategy toward true urea-based supramolecular Janus nanocylinders.
    Mots-clés : POLE 4, POLYMERES.

  • L. Chenneberg, C. Lévêque, V. Corcé, A. Baralle, J. - P. Goddard, C. Ollivier, et L. Fensterbank, « Single-Electron-Transfer Oxidation of Trifluoroborates and Silicates with Organic Reagents: A Comparative Study », Synlett, vol. 27, nᵒ 05, p. 731-735.

  • M. C. Chong, G. Reecht, H. Bulou, A. Boeglin, F. Scheurer, F. Mathevet, et G. Schull, « Narrow-Line Single-Molecule Transducer between Electronic Circuits and Surface Plasmons », Physical Review Letters, vol. 116, nᵒ 3, p. 036802.
    Résumé : A molecular wire containing an emitting molecular center is controllably suspended between the plasmonic electrodes of a cryogenic scanning tunneling microscope. Passing current through this circuit generates an ultranarrow-line emission at an energy of ≈1.5 eV which is assigned to the fluorescence of the molecular center. Control over the linewidth is obtained by progressively detaching the emitting unit from the surface. The recorded spectra also reveal several vibronic peaks of low intensities that can be viewed as a fingerprint of the emitter. Surface plasmons localized at the tip-sample interface are shown to play a major role in both excitation and emission of the molecular excitons.
    Mots-clés : POLE 4, POLYMERES.

  • M. W. Cooke, M. - P. Santoni, B. Hasenknopf, et G. S. Hanan, « Heteroleptic ruthenium(II) chromophores based on tunable polytopic 4′-(benzamidinato)-2,2′:6′,2′′-terpyridines », vol. 45, nᵒ 44, p. 17850-17858.
    Résumé : A modulable and simple approach towards heteroleptic ruthenium(II) complexes of amidine-based polypyridine ligands is presented. New complexes 1 and 2 ([(terpyridine)Ru(terpyridine-C6H4-C(NR)(NHR))]2+ with R = propyl and R = phenyl derivatives, respectively) were characterized by NMR spectroscopy in solution and by X-ray diffraction, which confirmed the obtention of the (E) stereoisomer alone. Depending on the bulkiness of the R-substituents introduced on the amidine moiety, rotational isomerism around the C–N bond could be observed at r.t. Spectroscopic and electrochemical studies showed that the nature of the R-substituents introduced on the amidine moiety can significantly influence the redox and ground-state acido-basic properties of the complexes, while maintaining their electronic features. This particular tunability of polytopic 4′-(amidinato)-terpyridines offers an interesting perspective for photoactive units in larger multi-functional arrays.
    Mots-clés : GOBS, POLE 3.

  • A. Desmarchelier, B. G. Alvarenga, X. Caumes, L. Dubreucq, C. Troufflard, M. Tessier, N. Vanthuyne, J. Idé, T. Maistriaux, D. Beljonne, P. Brocorens, R. Lazzaroni, M. Raynal, et L. Bouteiller, « Tuning the nature and stability of self-assemblies formed by ester benzene 1,3,5-tricarboxamides: the crucial role played by the substituents », vol. 12, nᵒ 37, p. 7824-7838.
    Résumé : As the benzene 1,3,5-tricarboxamide (BTA) moiety is commonly used as the central assembling unit for the construction of functionalized supramolecular architectures, strategies to tailor the nature and stability of BTA assemblies are needed. The assembly properties of a library of structurally simple BTAs derived from amino dodecyl esters (ester BTAs, 13 members) have been studied, either in the bulk or in cyclohexane solutions, by means of a series of analytical methods (NMR, DSC, POM, FT-IR, UV-Vis, CD, ITC, high-sensitivity DSC, SANS). Two types of hydrogen-bonded species have been identified and characterized: the expected amide-bonded helical rods (or stacks) that are structurally similar to those formed by BTAs with simple alkyl side chains (alkyl BTAs), and ester-bonded dimers in which the BTAs are connected by means of hydrogen bonds linking the amide N–H and the ester CO. MM/MD calculations coupled with simulations of CD spectra allow for the precise determination of the molecular arrangement and of the hydrogen bond pattern of these dimers. Our study points out the crucial influence of the substituent attached on the amino-ester α-carbon on the relative stability of the rod-like versus dimeric assemblies. By varying this substituent, one can precisely tune the nature of the dominant hydrogen-bonded species (stacks or dimers) in the neat compounds and in cyclohexane over a wide range of temperatures and concentrations. In the neat BTAs, stacks are stable up to 213 °C and dimers above 180 °C whilst in cyclohexane stacks form at c* > 3 × 10−5 M at 20 °C and dimers are stable up to 80 °C at 7 × 10−6 M. Ester BTAs that assemble into stacks form a liquid-crystalline phase and yield gels or viscous solutions in cyclohexane, demonstrating the importance of controlling the structure of these assemblies. Our systematic study of these structurally similar ester BTAs also allows for a better understanding of how a single atom or moiety can impact the nature and stability of BTA aggregates, which is of importance for the future development of functionalized BTA supramolecular polymers.
    Mots-clés : POLE 4, POLYMERES.

  • D. Diamante, S. Gabrieli, T. Benincori, G. Broggini, J. Oble, et G. Poli, « Dehydrogenative Allylic Aminations of But-3-enoic Acid Derivatives », ResearchGate.
    Résumé : Two complementary Pd-catalyzed protocols enabling the γ-selective intermolecular allylic amination of but-3-enoic acid derivatives are reported. These transformations can be successfully achieved...
    Mots-clés : POLE 1, ROCS.

  • F. J. S. Duarte, G. Poli, et M. J. Calhorda, « Mechanistic Study of the Direct Intramolecular Allylic Amination Reaction Catalyzed by Palladium(II) », ACS Catalysis, vol. 6, nᵒ 3, p. 1772-1784.
    Résumé : DFT calculations (PBE1PBE/6-31G(d,p), Def2-TZVPPD) were performed to study the intramolecular C–H amination of an unsaturated carbamate catalyzed by [Pd(LL)(OAc)2] (2), where LL is the bis(sulfoxide) ligand PhS(O)(CH2)2S(O)Ph. The coordination takes place by an associative path over a trigonal-bipyramidal transition state. The LL ligand undergoes a coordination shift from κ2S,S to κ1S, leaving an open position for binding of the substrate (C═C). In the next step, the C–H activation, the transition state for the hydrogen abstraction from the substrate to form the σ-allyl complex has an energy of 124.0 kJ mol–1, which is the highest energy in the whole mechanism (TOF-determining transition state). The σ-allyl converts easily in the π-allyl, the acetic acid molecule leaving the coordination sphere. The remaining acetate receives the second hydrogen from the NH group, while the newly formed acetic acid molecule is replaced by the pendant arm of the LL ligand, and the cyclization takes place (nucleophilic attack). During these changes, the metal is reduced to Pd(0) in the form of the Pd(0) complex of the oxazolidinone product, the most stable species in the cycle (TOF-determining intermediate). Either the C–H activation or the Pd(0) oxidation may be the step determining the energy span of the reaction, depending on reaction conditions.
    Mots-clés : POLE 1, ROCS.

  • J. Dubarle-Offner, J. Moussa, H. Amouri, B. Jouvelet, L. Bouteiller, et M. Raynal, « Induced Circular Dichroism in Phosphine Gold(I) Aryl Acetylide Urea Complexes through Hydrogen-Bonded Chiral Co-Assemblies », Chemistry – A European Journal, vol. 22, nᵒ 12, p. 3985-3990.
    Résumé : Phosphine gold(I) aryl acetylide complexes equipped with a central bis(urea) moiety form 1D hydrogen-bonded polymeric assemblies in solution that do not display any optical activity. Chiral co-assemblies are formed by simple addition of an enantiopure (metal-free) complementary monomer. Although exhibiting an intrinsically achiral linear geometry, the gold(I) aryl acetylide fragment is located in the chiral environment displayed by the hydrogen-bonded co-assemblies, as demonstrated by induced circular dichroism (ICD).
    Mots-clés : ARC, gold complexes, induced circular dichroism, POLE 1, POLE 4, POLYMERES, sergeants and soldiers, supramolecular chirality, supramolecular polymers.

  • Q. Dumont, M. Bárcenas, H. Dossmann, I. Bailloux, C. Buisson, N. Mechin, A. Molina, F. Lasne, N. S. Rannulu, et R. B. Cole, « Improved Steroids Detection and Evidence for Their Regiospecific Decompositions Using Anion Attachment Mass Spectrometry », Analytical Chemistry, vol. 88, nᵒ 7, p. 3585-3591.
    Résumé : Nonpolar anabolic steroids are doping agents that typically do not provide strong signals by electrospray ionization-mass spectrometry (ESI-MS) owing especially to the low polarity of the functional groups present. We have investigated the addition of anions, in ammonium salt form, to anabolic steroid samples as ionization enhancers and have confirmed that lower instrumental limits of detection (as low as 10 ng/mL for fluoxymesterone-M) are obtained by fluoride anion attachment mass spectrometry, as compared to ESI(+)/(−) or atmospheric pressure photoionization (APPI)(+). Moreover, collision-induced decomposition (CID) spectra of precursor fluoride adducts of the bifunctional steroid “reduced pregnenolone” (containing two hydroxyl groups) and its d4-analogue provide evidence of regiospecific decompositions after attachment of fluoride anion to a specific hydroxyl group of the steroid. This type of charting of specific CID reaction pathways can offer value to selected reaction monitoring experiments (SRM) as it may result in a gain in selectivity in detection as well as in improvements in quantification.
    Mots-clés : CSOB, POLE 3.

  • B. J. Fallon, V. Corcé, M. Amatore, C. Aubert, F. Chemla, F. Ferreira, A. Perez-Luna, et M. Petit, « A well-defined low-valent cobalt catalyst Co(PMe3)4 with dimethylzinc: a simple catalytic approach for the reductive dimerization of benzyl halides ».
    Résumé : Herein, we report the first catalytic version of a cobalt-catalysed reductive homocoupling of benzyl halides which proceeds with low catalyst loadings (0.5 to 5 mol%). By synthetizing each cobalt intermediate we demonstrate that reaction proceeds through two single electron transfers (SET) and that dimethylzinc is only involved in the regeneration of the catalytic species.
    Mots-clés : MACO, POLE 1, ROCS.

  • B. J. Fallon, E. Derat, M. Amatore, C. Aubert, F. Chemla, F. Ferreira, A. Perez-Luna, et M. Petit, « C2-Alkylation and Alkenylation of Indoles Catalyzed by a Low-Valent Cobalt Complex in the Absence of Reductant », Organic Letters, vol. 18, nᵒ 9, p. 2292-2295.
    Résumé : Herein an extremely versatile, well-defined, low-valent cobalt catalyst [Co(PMe3)4] capable of intermolecular and intramolecular imine-directed C2-alkylation and alkenylation of indoles is reported. The reaction proceeds in the absence of reducing agents or additives, affording a range of substituted indoles and dihydropyrroloindoles in high yields and regioselectivities. With the aid of deuterium labeling studies and DFT (Density Functional Theory) calculations, a mechanism is proposed that is based on a Ligand-to-Ligand Hydrogen Transfer pathway.

  • C. Fopp, K. Isaac, E. Romain, F. Chemla, F. Ferreira, O. Jackowski, M. Oestreich, et A. Perez-Luna, « Stereodivergent Synthesis of β-Heteroatom-Substituted Vinyl­silanes by Sequential Silylzincation–Copper(I)-Mediated Electrophilic­ Substitution », Synthesis.
    Résumé : Thieme E-Books & E-Journals
    Mots-clés : POLE 1, ROCS.

  • S. L. Gac, B. Boitrel, M. Sollogoub, et M. Ménand, « Protonated hexaphyrin–cyclodextrin hybrids: molecular recognition tuned by a kinetic-to-thermodynamic topological adaptation », vol. 52, nᵒ 60, p. 9347-9350.
    Résumé : Protonation study of [26/28]hexaphyrin-capped cyclodextrins revealed a temperature controlled conformational transition of the cap. The hexaphyrin undergoes a rectangular-to-triangular shape-shifting which strongly modifies the shape of the confined environment featured by the hybrids, and ultimately affects the encapsulation of the counterions. It provides an attractive access to innovative allosteric host–guest systems.
    Mots-clés : GOBS, POLE 3.

  • Y. Gao, X. He, F. Ding, et Y. Zhang, « Recent Progress in Chemical Syntheses of Sphingosines and Phytosphingosines », Synthesis, vol. 48, nᵒ 23, p. 4017-4037.
    Résumé : Thieme E-Books & E-Journals
    Mots-clés : GOBS, POLE 3.

  • 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, EPOM, hydrophobic interactions, NMR spectroscopy, POLE 2, porous capsules.

  • 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.

  • 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 », 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.

  • J. R. Hernandez, F. Chemla, F. Ferreira, O. Jackowski, J. Oble, A. Perez-Luna, et G. Poli, « tert-Butanesulfinamides as Nitrogen Nucleophiles in Carbon–Nitrogen Bond Forming Reactions », CHIMIA International Journal for Chemistry, vol. 70, nᵒ 1, p. 84-92.
    Résumé : The use of tert-butanesulfinamides as nitrogen nucleophiles in carbon–nitrogen bond forming reactions is reviewed. This field has grown in the shadow of the general interest in N-tert-butanesulfinyl imines for asymmetric synthesis and occupies now an important place in its own right in the chemistry of the chiral amine reagent tert-butanesulfinamide. This article provides an overview of the area and emphasizes recent contributions wherein the tert-butanesulfinamides act as chiral auxiliaries or perform as nitrogen donors in metal-catalyzed amination reactions.
    Mots-clés : 2015, amination, Chiral Nucleophiles, POLE 1, ROCS, Tert-Butanesulfinamide.

  • 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, EPOM, 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, EPOM, Hydrodenitrogenation, Hydrodesulphurization, Inhibition, NiMoS, Nitrogen compounds, POLE 2, Vibrational modes.

  • 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, EPOM, POLE 2.

  • G. Izzet, F. Volatron, et A. Proust, « Tailor-made Covalent Organic-Inorganic Polyoxometalate Hybrids: Versatile Platforms for the Elaboration of Functional Molecular Architectures », The Chemical Record, p. n/a-n/a.
    Résumé : Post-functionalization of organically modified polyoxometalates (POMs) is a powerful synthetic tool to devise functional building blocks for the rational elaboration of POM-based molecular materials. In this personal account we focus on iodoaryl-terminated POM platforms, describe reliable routes to the synthesis of covalent organic-inorganic POM-based hybrids and their integration into advanced molecular architectures or multi-scale assemblies as well as their immobilization onto surfaces. Valorisation of the remarkable redox properties of POMs in the fields of artificial synthesis and molecular electronic is especially considered.
    Mots-clés : artificial photosynthesis, EPOM, modified electrodes, organic-inorganic hybrids, palladium cross-coupling, POLE 2, Polyoxometalates.

  • 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 : EPOM, 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 », ResearchGate.
    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.

  • 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.

  • N. B. Kingsley, T. J. Doyon, et L. E. Shephard, « Synthesis and characterization of dialkylaluminum arylimine complexes », Journal of Organometallic Chemistry, vol. 801, p. 48-53.
    Résumé : A series of six new aluminum(III) complexes with o-metalated arylimine ligands [o-C6H4(CHNR') (R' = 2,6-iPr2C6H3, 2,6-Me2C6H3)] have been synthesized from the reactions of R2AlCl (R = Me, Et) with o-C6H4(CHNR')Li (R' = 2,6-iPr2C6H3, 2,6-Me2C6H3, t-Bu) in pentane. The complexes all have 4 coordinate pseudo-tetrahedral aluminum centers ligated by two alkyl groups and one bidentate ligand moiety. All six complexes 2a–4b have been fully characterized by 1H and 13C NMR spectroscopy and the molecular structures of 2b and 3a were determined by X-ray crystallography.
    Mots-clés : Aluminum, Arylimine, CHEMBIO, o-Metalated, POLE 3.

  • 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.

  • 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 (Weinheim an Der Bergstrasse, Germany), 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 », 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 », 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.

  • 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 », Org. Chem. Front., vol. 3, nᵒ 4, p. 462-465.

  • 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 », 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 : E-POM, EPOM, POLE 2.

  • 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, 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. n/a-n/a.
    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.

  • 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.

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