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  • H. Amouri, « Luminescent Complexes of Platinum, Iridium, and Coinage Metals Containing N-Heterocyclic Carbene Ligands: Design, Structural Diversity, and Photophysical Properties », Chemical Reviews, vol. 123, nᵒ 1, p. 230-270, janv. 2023.
    Résumé : The employment of N-heterocyclic carbenes (NHCs) to design luminescent metal compounds has been the focus of recent intense investigations because of the strong σ-donor properties, which bring stability to the whole system and tend to push the d–d dark states so high in energy that they are rendered thermally inaccessible, thereby generating highly emissive complexes for useful applications such as organic light-emitting diodes (OLEDs), or featuring chiroptical properties, a field that is still in its infancy. Among the NHC complexes, those containing organic chromophores such as naphthalimide, pyrene, and carbazole exhibit rich emission behavior and thus have attracted extensive interest in the past five years, especially carbene coinage metal complexes with carbazolate ligands. In this review, the design strategies of NHC-based luminescent platinum and iridium complexes with large spin–orbit-coupling (SOC) are described first. Subsequent paragraphs illustrate the recent advances of luminescent coinage metal complexes with nucleophilic- and electrophilic-based carbenes based on silver, gold, and copper metal complexes that have the ability to display rich excited state emissions in particular via thermally activated delayed fluorescence (TADF). The luminescence mechanism and excited state dynamics are also described. We then summarize the advance of NHC–metal complexes in the aforementioned fields in recent years. Finally, we propose the development trend of this fast-growing field of luminescent NHC–metal complexes.
    Mots-clés : ARC.

  • M. Balas, A. Mayoufi, R. Villanneau, et F. Launay, « Revisiting the Mukaiyama-type epoxidation for the conversion of styrene into styrene carbonate in the presence of O <sub>2</sub> and CO <sub>2</sub> », Reaction Chemistry & Engineering, p. 10.1039.D2RE00330A, 2023.
    Résumé : Alkene epoxidation using the Mukaiyama process involving O 2 and a sacrificial aldehyde, as the first step of the global alkene oxidative carboxylation, does not necessarily require a metal catalyst. , Since its first report in the early 1990s, Mukaiyama-type aerobic epoxidation involving the presence of an aldehyde as an electron donor is considered as an interesting oxidation reaction. Among the various metal catalysts efficient for this process, salen-type complexes have many advantages: i) cheap Schiff-base ligands can be easily synthesized and functionalized, ii) their metal complexes are described with most transition metals from the periodic table and iii) these compounds are also efficient for the catalytic formation of cyclic carbonates from epoxides and CO 2 , which makes them ideal candidates for the oxidative carboxylation of alkenes. The present work aimed at revisiting the aerobic oxidation of styrene using Cr( iii ) and Mn( iii ) salen complexes in the presence of isobutyraldehyde with the idea to further use these complexes (without any work-up), as co-catalysts for the formation of styrene carbonate under CO 2 pressure. However, contrary to what is often described in the literature, the present study showed that the introduction of a metal catalyst is not necessary for the epoxidation of styrene at 80 °C in benzonitrile. In our hands, yields of ca. 15% of styrene carbonate were obtained from styrene using O 2 (3.5 bar) and CO 2 (11 bar) as reagents in the presence of isobutyraldehyde (2.5 eq), tetrabutylammonium bromide ( ca. 2 mol%) and the Cr( iii ) salen complex ( ca. 1 mol%). Apparently, the oxidation of Cr( iii ) to Cr( vi ) species in the presence of O 2 and isobutyraldehyde is detrimental to the kinetics of the tetrabutylammonium bromide-catalyzed cycloaddition of CO 2 to styrene oxide.
    Mots-clés : E-POM, POLE 2.

  • G. Delecourt, L. Plet, Y. L. Guen, O. Tezgel, G. Tresset, P. Midoux, T. Montier, V. Bennevault, et P. Guégan, « Synthesis of Double Hydrophilic Block Copolymers Poly(2-isopropyl-2-oxazoline-b-ethylenimine) and their DNA Transfection Efficiency », Macromolecular Bioscience, vol. 23, nᵒ 1, p. 2200296, 2023.
    Résumé : Gene delivery is now a part of the therapeutic arsenal for vaccination and treatments of inherited or acquired diseases. Polymers represent an opportunity to develop new synthetic vectors for gene transfer, with a prerequisite of improved delivery and reduced toxicity compared to existing polymers. Here, the synthesis in a two-step's procedure of linear poly(ethylenimine-b-2-isopropyl-2-oxazoline) block copolymers with the linear polyethylenimine (lPEI) block of various molar masses is reported; the molar mass of the poly(2-isopropyl-2-oxazoline) (PiPrOx) block has been set to 7 kg mol−1. Plasmid DNA condensation is successfully achieved, and in vitro transfection efficiency of the copolymers is at least comparable to that obtained with the lPEI of same molar mass. lPEI-b-PiPrOx block copolymers are however less cytotoxic than their linear counterparts. PiPrOx can be a good alternative to PEG which is often used in drug delivery systems. The grafting of histidine moieties on the lPEI block of lPEI-b-PiPrOx does not provide any real improvement of the transfection efficiency. A weak DNA condensation is observed, due to increased steric hindrance along the lPEI backbone. The low cytotoxicity of lPEI-b-PiPrOx makes this family a good candidate for future gene delivery developments.
    Mots-clés : gene therapy, oxazoline, PEGylation alternative, PEI, POLYMERES.

  • P. Idlas, E. Lepeltier, G. Bastiat, P. Pigeon, M. J. McGlinchey, N. Lautram, A. Vessières, G. Jaouen, et C. Passirani, « Physicochemical Characterization of Ferrocifen Lipid Nanocapsules: Customized Drug Delivery Systems Guided by the Molecular Structure », Langmuir, janv. 2023.
    Résumé : Ferrocifens, lipophilic organometallic complexes, comprise a biologically active redox motif [ferrocenyl-ene-p-phenol] which confers very interesting cytotoxic properties to this family. However, because of their highly lipophilic nature, a formulation stage is required before being administered in vivo. In recent decades, ferrocifen lipid nanocapsules (LNCs) have been successfully formulated and have demonstrated anticancer activity on multidrug-resistant cancers in several mice and rat models (glioblastoma, breast cancer, and metastatic melanoma). A recent family of ferrocifens (succinimidoalkyl-ferrociphenols, including P722) appears to be most efficacious on several resistant cancer cell lines, with IC50 values in the nanomolar range together with promising in vivo results on murine ovarian cancer models. As LNCs are composed of an oily core (caprylic/capric triglycerides), modulation of the succinimido-ferrociphenol lipophilicity could be a valuable approach toward improving the drug loading in LNCs. As the drug loading of the diphenol P722 in LNCs was low, it was structurally modified to increase its lipophilicity and thereby the payload in LNCs. Chemical modification led to a series of five succinimido-ferrocifens. Results confirmed that these slight structural modifications led to increased drug loading in LNCs for all ferrocifens, with no reduction of their cytotoxicity on the SKOV3 ovarian cancer cell line. Interestingly, encapsulation of two of the ferrocifens, diester P769 and monophenolic ester (E)-P998, led to the formation of a gel. This was unprecedented behavior, a phenomenon that could be rationalized in terms of the positioning of ferrocifens in LNCs as shown by the decrease of interfacial tension measurements at the water/oil interface. Moreover, these results highlighted the importance of obtaining a gel of this particular motif, in which the acetylated phenolic ring and the succinimidoalkyl moieties are mutually cis relative to the central double bond. Promising perspectives to use these ferrocifen-loaded LNCs to treat glioblastoma could be readily envisaged by local application of the gel in the cavity after tumor resection.
    Mots-clés : CHEMBIO, POLE 3.

  • E. Liu, S. Cherraben, L. Boulo, C. Troufflard, B. Hasenknopf, G. Vives, et M. Sollogoub, « A molecular information ratchet using a cone-shaped macrocycle », Chem, p. S245192942200660X, 2023.

  • H. Madec, F. Figueiredo, K. Cariou, S. Roland, M. Sollogoub, et G. Gasser, « Metal complexes for catalytic and photocatalytic reactions in living cells and organisms », Chemical Science, vol. 14, nᵒ 3, p. 409-442, 2023.
    Résumé : This review presents discrete metal complexes that catalyse or photocatalyse reactions within living cells or living organisms. , The development of organometallic catalysis has greatly expanded the synthetic chemist toolbox compared to only exploiting “classical” organic chemistry. Although more widely used in organic solvents, metal-based catalysts have also emerged as efficient tools for developing organic transformations in water, thus paving the way for further development of bio-compatible reactions. However, performing metal-catalysed reactions within living cells or organisms induces additional constraints to the design of reactions and catalysts. In particular, metal complexes must exhibit good efficiency in complex aqueous media at low concentrations, good cell specificity, good cellular uptake and low toxicity. In this review, we focus on the presentation of discrete metal complexes that catalyse or photocatalyse reactions within living cells or living organisms. We describe the different reaction designs that have proved to be successful under these conditions, which involve very few metals (Ir, Pd, Ru, Pt, Cu, Au, and Fe) and range from in cellulo deprotection/decaging/activation of fluorophores, drugs, proteins and DNA to in cellulo synthesis of active molecules, and protein and organelle labelling. We also present developments in bio-compatible photo-activatable catalysts, which represent a very recent emerging area of research and some prospects in the field.
    Mots-clés : GOBS, POLE 3.

  • A. Mamontov, L. Chang, H. Dossmann, B. Bertrand, L. Dechoux, et S. Thorimbert, « Iron Catalyzed Dearomatization of Pyridines into Annelated Azepine Derivatives in a One-Step, Three-Component Reaction », Organic Letters, vol. 25, nᵒ 1, p. 256-260, 2023.
    Résumé : Commercially available Fe(TTP)Cl catalyzes three-component dearomative formal cycloaddition reactions between pyridines, diazo compounds, and coumalates. Diversely substituted annelated seven-membered N-heterocycles could be generated in less than 10 min in one step at room temperature. The reaction is compatible to gram scale. The extension to benzimidazoles in place of pyridines has been successfully demonstrated. The mechanism of this reaction has been carefully examined by computational studies that corroborate the observed regioselectivities.
    Mots-clés : CHEMBIO, CSOB, POLE 3.

  • A. Mascherpa, N. Ishii, A. Tayagui, J. Liu, M. Sollogoub, et A. J. Fairbanks, « Lysosomal Targeting of β‐Cyclodextrin », Chemistry – A European Journal, vol. 29, nᵒ 4, janv. 2023.

  • V. Pellas, F. Sallem, J. Blanchard, A. Miche, S. M. Concheso, C. Méthivier, M. Salmain, et S. Boujday, « Silica-coated gold nanorods biofunctionalization for localized surface plasmon resonance (LSPR) biosensing », Talanta, vol. 255, p. 124245, avr. 2023.
    Résumé : We introduce here the engineering of nanobiosensors designed from gold nanorods coated with an ultrathin layer of silica (AuNR@SiO2) and biofunctionalized with antibodies for the Localized Surface Plasmon Resonance (LSPR) biosensing of proteins. Despite the outstanding properties of AuNRs, their use for LSPR biosensing is limited due to the presence of the surfactant cetyltrimethylammonium bromide (CTAB) – mandatory for their synthesis - which forms a strongly-bounded and positively-charged bilayer at their surface and significantly complicates their bio-functionalization. When coated with a thin layer of silica, these nanomaterials exhibit an improved sensitivity to refractive index change which augurs for better analytical performances. Here, we undertook an in-depth investigation of the biofunctionalization of AuNR@SiO2 via three different routes to design and test a label-free LSPR biosensor operating in solution. In the first route, we took advantage of the negatively charged external silica shell to immobilize anti-rabbit IgG antibody by electrostatic physisorption. In the second and third routes, the silica surface was reacted with thiol or aldehyde terminated silanes, subsequently utilized to covalently attach anti-rabbit IgG antibody to the surface. The resulting nanoprobes were characterized by a wide range of physical methods (TEM, XPS, DLS, ELS and UV-Visible spectroscopy) then tested for the biosensing of rabbit-IgG. The three nanobiosensors maintain an excellent colloidal stability after analyte recognition and exhibit extremely high analytical performances in terms of specificity and dynamic range, with an LoD down to 12 ng/mL.
    Mots-clés : CHEMBIO, Core−Shell, Gold nanorods, Immunosensing, LSPR, POLE 3, Silica coating, Surface chemistry.

  • A. Vessières et M. J. McGlinchey, « Bioorganometallic chemistry – the early years », Journal of Organometallic Chemistry, vol. 987-988, p. 122623, avr. 2023.
    Résumé : Bioorganometallic chemistry is now a maturing field attracting researchers around the world, and also across the Periodic Table. It has found applications in a broad range of areas such as drug discovery, biocatalysis and imaging. We review here the first experiments carried out in the early 1980′s at the Ecole Nationale Supérieure de Chimie de Paris under the leadership of Gérard Jaouen, a key figure and visionary in the development of this theme. However, they also required important contributions from Canadian collaborators with expertise in NMR and IR spectroscopy, together with the availability of more powerful and versatile instrumentation. This collaboration found its fulfillment in the demonstration of the use of metal carbonyl complexes (exemplified by an estradiol derivative labeled by a Cr(CO)3 unit) as non-isotopic tracers allowing the detection of estradiol receptors, an essential marker for setting up a targeted therapy for breast cancer. This approach was based on the premise that the intense metal carbonyl stretching vibrations are found in a window (2100–1850 cm−1) where the protein itself does not absorb. The field was extended to the arena of non-isotopic immunoassays, including the simultaneous detection of multiple antiepileptic drugs bearing metal carbonyl labels. More recently, taking advantage of the new technique of atomic force microscopy-infrared spectroscopy (AFM-IR) it has been possible to accomplish direct tracing of these complexes in cells. The contributions of the original group of workers in the field are highlighted, and placed in the perspective of today's subsequent emphasis on the management of previously untreatable cancers.
    Mots-clés : 2D NMR, CHEMBIO, Estrogen receptor, FT-IR spectroscopy, Immunoassay, Metal carbonyls, Organometallic tracers, POLE 3.


  • « Boron, silicon, nitrogen and sulfur-based contemporary precursors for the generation of alkyl radicals by single electron transfer and their synthetic utilization - Chemical Society Reviews (RSC Publishing) », 2022. [Online]. Available: [Accessed: 31-janv.-2023].
    Mots-clés : CHEMBIO, MACO, POLE 1, POLE 3.

  • P. Aoun, A. Hammoud, M. A. Martínez-Aguirre, L. Bouteiller, et M. Raynal, « Asymmetric hydroamination with far fewer chiral species than copper centers achieved by tuning the structure of supramolecular helical catalysts », Catalysis Science & Technology, vol. 12, nᵒ 3, p. 834-842, févr. 2022.
    Résumé : The incorporation of a few chiral monomers (the “sergeants”) in a backbone composed of a majority of achiral monomers (the “soldiers”) is a well-established strategy to control the handedness of helical polymers. However, the implementation of this “sergeants-and-soldiers” effect in asymmetric catalysis is still at its infancy, with only limited examples for which the sergeant amount is actually in lower amount than the (metal) catalytic unit. Herein, supramolecular co-polymers composed of a benzene-1,3,5-tricarboxamide (BTA) phosphine soldier and a catalytically-inactive BTA sergeant were evaluated in the copper-catalysed hydroamination of styrene. Screening of various BTA ligands revealed the marked influence of substituents on the aryl group of the BTA phosphine ligand, the 3,5-bis-CF3-substituted ligand providing the highest rate and enantioselectivity. Thorough optimization of the reaction parameters led to a robust protocol for the generation of the amine product in high yield (82 ± 4%) and moderate e.e. (68 ± 6%). Addition of an achiral BTA additive was found to be beneficial for improving the yield (80–99%), enantioselectivity (up to 81% e.e.) and “sergeants-and-soldiers” effect displayed by the supramolecular helical catalyst. Consequently, an enantio-enriched product (75% e.e.) was afforded with as low as 0.51 mol% of sergeant in the catalytic mixture, i.e. one chiral molecule for 10 copper centers.
    Mots-clés : POLYMERES.

  • E. Atrián-Blasco, L. de Cremoux, X. Lin, R. Mitchell-Heggs, L. Sabater, S. Blanchard, et C. Hureau, « Keggin-type polyoxometalates as Cu( <span style="font-variant:small-caps;">ii</span> ) chelators in the context of Alzheimer's disease », Chemical Communications, vol. 58, nᵒ 14, p. 2367-2370, 2022.
    Résumé : Keggin-type POMs extract Cu( ii ) from the Alzheimer's-related amyloid-β peptide. They prevent Cu(Aβ) ROS production, while ill-defined Cu(Aβ) aggregates are switched to fibrils due to Cu(POM) modulation of the apo-Aβ's assembly. , Two Keggin polyoxometalates were used as new copper ligands to counteract the effects of Cu II (Amyloid-β) interaction. Their ability to remove Cu II from Cu II (Amyloid-β), to stop Cu II (Amyloid-β) induced formation of reactive oxygen species and to restore apo-like self-assembly of Cu II (Amyloid-β) was shown.
    Mots-clés : E-POM, POLE 2.

  • M. Balas, R. Villanneau, et F. Launay, « Bibliographic survey of the strategies implemented for the one-pot synthesis of cyclic carbonates from styrene and other alkenes using CO2 and green oxidants », Journal of CO2 Utilization, vol. 65, p. 102215, 2022.

  • S. Bassoli, A. Schallmey, J. Oble, G. Poli, et A. Pradal, « Short Hydroacylation-Based Synthesis of Four Aryl-3-hydroxypropanones, Predictable Biomass-Derived C9 Platform Molecules », Catalysis Research, vol. 02, nᵒ 04, p. 036, oct. 2022.
    Résumé : A two-step protocol for the synthesis of aryl-3-hydroxypropanones, which were regarded as lignin degradation products, was proposed herein. This protocol provided a more rapid and easier access to aryl-3-hydroxypropanones, and aryl-3-hydroxypropanones were expected to be ideal platform molecules for the synthesis of more complex value-added targets.
    Mots-clés : POLE 1, ROCS.

  • P. Bayat, D. Gatineau, D. Lesage, A. Martinez, et R. B. Cole, « Benchmarking higher energy collision dissociation (HCD) by investigation of binding energies of gas‐phase host–guest complexes of hemicryptophane cages », Journal of Mass Spectrometry, vol. 57, nᵒ 9, p. e4879, 2022.

  • F. Bigi, D. Cauzzi, N. Della Ca’, M. Malacria, R. Maggi, E. Motti, Y. Wang, et G. Maestri, « Evolution of Triangular All-Metal Aromatic Complexes from Bonding Quandaries to Powerful Catalytic Platforms », ACS Organic & Inorganic Au, vol. 2, nᵒ 5, p. 373-385, oct. 2022.
    Résumé : This manuscript describes an overview on the literature detailing the observation of trinuclear complexes that present delocalized metal–metal bonds similar to those of regular aromatics, which are formed combining main group elements. A particular emphasis is given to the structural and electronic features of aromatic clusters that are sufficiently stable to allow their isolation. In parallel to the description of their key bonding properties, the work presents reported catalytic applications of these complexes, which already span from elaborated C–C-forming cascades to highly efficient cross-coupling methods. These examples present peculiar aspects of the unique reactivity exerted by all-metal aromatic complexes, which can often be superior to their established, popular mononuclear peers in terms of chemoselectivity and chemical robustness.
    Mots-clés : MACO, POLE 1.

  • F. Bouihi, B. Schmaltz, F. Mathevet, D. Kreher, J. Faure-Vincent, C. Yildirim, A. Elhakmaoui, J. Bouclé, M. Akssira, F. Tran-Van, et M. Abarbri, « D-π-A-Type Pyrazolo[1,5-a]pyrimidine-Based Hole-Transporting Materials for Perovskite Solar Cells: Effect of the Functionalization Position », Materials, vol. 15, nᵒ 22, p. 7992, janv. 2022.
    Résumé : Donor–acceptor (D–A) small molecules are regarded as promising hole-transporting materials for perovskite solar cells (PSCs) due to their tunable optoelectronic properties. This paper reports the design, synthesis and characterization of three novel isomeric D-π-A small molecules PY1, PY2 and PY3. The chemical structures of the molecules consist of a pyrazolo[1,5-a]pyrimidine acceptor core functionalized with one 3,6-bis(4,4′-dimethoxydiphenylamino)carbazole (3,6-CzDMPA) donor moiety via a phenyl π-spacer at the 3, 5 and 7 positions, respectively. The isolated compounds possess suitable energy levels, sufficient thermal stability (Td > 400 °C), molecular glass behavior with Tg values in the range of 127–136 °C slightly higher than that of the reference material Spiro-OMeTAD (126 °C) and acceptable hydrophobicity. Undoped PY1 demonstrates the highest hole mobility (3 × 10−6 cm2 V−1 s−1) compared to PY2 and PY3 (1.3 × 10−6 cm2 V−1 s−1). The whole isomers were incorporated as doped HTMs in planar n-i-p PSCs based on double cation perovskite FA0.85Cs0.15Pb(I0.85Br0.15)3. The non-optimized device fabricated using PY1 exhibited a power conversion efficiency (PCE) of 12.41%, similar to that obtained using the reference, Spiro-OMeTAD, which demonstrated a maximum PCE of 12.58% under the same conditions. The PY2 and PY3 materials demonstrated slightly lower performance in device configuration, with relatively moderate PCEs of 10.21% and 10.82%, respectively, and slight hysteresis behavior (−0.01 and 0.02). The preliminary stability testing of PSCs is also described. The PY1-based device exhibited better stability than the device using Spiro-OMeTAD, which could be related to its slightly superior hydrophobic character preventing water diffusion into the perovskite layer.
    Mots-clés : 3, 5-a]pyrimidine, 6-CzDMPA, D-π-A, hole-transporting materials, perovskite solar cells, POLYMERES, pyrazolo[1.

  • N. A. Burger, G. Meier, L. Bouteiller, B. Loppinet, et D. Vlassopoulos, « Dynamics and Rheology of Supramolecular Assemblies at Elevated Pressures », The Journal of Physical Chemistry B, vol. 126, nᵒ 35, p. 6713-6724, sept. 2022.
    Résumé : A methodology to investigate the linear viscoelastic properties of complex fluids at elevated pressures (up to 120 MPa) is presented. It is based on a dynamic light scattering (DLS) setup coupled with a stainless steel chamber, where the test sample is pressurized by means of an inert gas. The viscoelastic spectra are extracted through passive microrheology. We discuss an application to hydrogen-bonding motif 2,4-bis(2-ethylhexylureido)toluene (EHUT), which self-assembles into supramolecular structures (tubes and filaments) in apolar solvents dodecane and cyclohexane. High levels of pressure (roughly above 20 MPa) are found to slow down the terminal relaxation process; however, the increases in the entanglement plateau modulus and the associated persistence length are not significant. The concentration dependence of the plateau modulus, relaxation times (fast and slow), and correlation length is practically the same for all pressures and exhibits distinct power-law behavior in different regimes. Within the tube phase in dodecane, the relative viscosity increment is weakly enhanced with increasing pressure and reaches a plateau at about 60 MPa. In fact, depending on concentration, the application of pressure in the tube regime may lead to a transition from a viscous (unentangled) to a viscoelastic (partially entangled to well-entangled) solution. For well-entangled, long tubes, the extent of the plateau regime (ratio of high- to low-moduli crossover frequencies) increases with pressure. The collective information from these observations is summarized in a temperature–pressure state diagram. These findings provide ingredients for the formulation of a solid theoretical framework to better understand and exploit the role of pressure in the structure and dynamics of supramolecular polymers.
    Mots-clés : POLYMERES.

  • N. A. Burger, G. Pembouong, L. Bouteiller, D. Vlassopoulos, et B. Loppinet, « Complete Dynamic Phase Diagram of a Supramolecular Polymer », Macromolecules, vol. 55, nᵒ 7, p. 2609-2614, avr. 2022.
    Résumé : We revisit the equilibrium phase diagram of the much-studied model supramolecular polymer, 2,4-bis(2-ethylhexylureido)toluene (EHUT) in nonpolar solvents and provide unambiguous evidence of a much richer behavior, characterized by four distinct regimes. Typically, two types of self-assembled structures are formed: tubes (filaments) at higher (lower) concentrations and lower (higher) temperatures. The tube structure forms viscoelastic solutions that had been characterized by rheology, however, without detailed analysis of the experimental signals. Here, we combine rheology and microrheology to establish the complete dynamic phase diagram of EHUT in dodecane. It still comprises two structures, tubes and filaments, with the transition temperature being almost constant over the examined wide concentration range, as confirmed with the help of complementary differential scanning calorimetry measurements. The tubes are found to exist in three dynamic states with increasing concentration, unentangled, partially entangled, and well entangled, which are separated by isolength lines. We present criteria for unambiguously identifying these phases and discuss their distinct concentration and temperature dependencies. The new, complete phase diagram may serve as a guide for investigating other supramolecular polymers with tunable rheology and, more importantly, providing insights into a universal description of one-dimensional self-assembled structures by linking this class of materials with the classic wormlike surfactant micelles, for which the partially and well-entangled regimes were recently elucidated.
    Mots-clés : POLYMERES.

  • A. I. Carbajo‐Gordillo, J. López‐Fernández, J. M. Benito, J. L. Jiménez Blanco, M. L. Santana‐Armas, G. Marcelo, C. Di Giorgio, C. Przybylski, C. Ortiz Mellet, C. Tros de Ilarduya, F. Mendicuti, et J. M. García Fernández, « Enhanced Gene Delivery Triggered by Dual pH/Redox Responsive Host‐Guest Dimerization of Cyclooligosaccharide Star Polycations », Macromolecular Rapid Communications, vol. 43, nᵒ 11, p. 2200145, 2022.

  • F. Célerse, T. J. Inizan, L. Lagardère, O. Adjoua, P. Monmarché, Y. Miao, E. Derat, et J. - P. Piquemal, « An Efficient Gaussian-Accelerated Molecular Dynamics (GaMD) Multilevel Enhanced Sampling Strategy: Application to Polarizable Force Fields Simulations of Large Biological Systems », Journal of Chemical Theory and Computation, vol. 18, nᵒ 2, p. 968-977, févr. 2022.
    Résumé : We introduce a novel multilevel enhanced sampling strategy grounded on Gaussian-accelerated Molecular Dynamics (GaMD). First, we propose a GaMD multi-GPUs-accelerated implementation within the Tinker-HP molecular dynamics package. We introduce the new “dual-water” mode and its use with the flexible AMOEBA polarizable force field. By adding harmonic boosts to the water stretching and bonding terms, it accelerates the solvent–solute interactions while enabling speedups, thanks to the use of fast multiple–time step integrators. To further reduce the time-to-solution, we couple GaMD to Umbrella Sampling (US). The GaMD─US/dual-water approach is tested on the 1D Potential of Mean Force (PMF) of the solvated CD2–CD58 system (168 000 atoms), allowing the AMOEBA PMF to converge within 1 kcal/mol of the experimental value. Finally, Adaptive Sampling (AS) is added, enabling AS–GaMD capabilities but also the introduction of the new Adaptive Sampling–US–GaMD (ASUS–GaMD) scheme. The highly parallel ASUS–GaMD setup decreases time to convergence by, respectively, 10 and 20 times, compared to GaMD–US and US. Overall, beside the acceleration of PMF computations, Tinker-HP now allows for the simultaneous use of Adaptive Sampling and GaMD-”dual water” enhanced sampling approaches increasing the applicability of polarizable force fields to large-scale simulations of biological systems.
    Mots-clés : MACO, POLE 1.

  • L. Chazot-Franguiadakis, J. Eid, M. Socol, B. Molcrette, P. Guégan, M. Mougel, A. Salvetti, et F. Montel, « Optical Quantification by Nanopores of Viruses, Extracellular Vesicles, and Nanoparticles », Nano Letters, vol. 22, nᵒ 9, p. 3651-3658, mai 2022.
    Résumé : Nanopores combined with optical approaches can be used to detect viral particles. In this work, we demonstrate the ability of hydrodynamical driving and optical sensing to identify and quantify viral particles in a biological sample. We have developed a simple and rapid method which requires only fluorescent labeling of the particles and can therefore be applied to a wide range of virus type. The system operates in real time and at the single particle level while providing a low error on concentration (4%) and a low limit of detection of 105 particles/mL for an acquisition time of 60 s with the ability to increase the acquisition time to achieve a lower limit.
    Mots-clés : POLYMERES.

  • V. Corcé, C. Ollivier, et L. Fensterbank, « Boron, silicon, nitrogen and sulfur-based contemporary precursors for the generation of alkyl radicals by single electron transfer and their synthetic utilization », Chemical Society Reviews, vol. 51, nᵒ 4, p. 1470-1510, févr. 2022.
    Résumé : Recent developments in the use of boron, silicon, nitrogen and sulfur derivatives in single-electron transfer reactions for the generation of alkyl radicals are described. Photoredox catalyzed, electrochemistry promoted or thermally-induced oxidative and reductive processes are discussed highlighting their synthetic scope and discussing their mechanistic pathways.
    Mots-clés : CHEMBIO, MACO, POLE 1, POLE 3.

  • S. Curpanen, G. Poli, A. Perez-Luna, et J. Oble, « C3−H Silylation of Furfurylimines: Direct Access to a Novel Biobased Versatile Synthetic Platform Derived from Furfural », Asian Journal of Organic Chemistry, vol. 11, nᵒ 7, p. e202200199, 2022.
    Résumé : Herein we report directed iridium-catalyzed C3−H silylation of furfuryl imines, which grants access to versatile synthetic platforms. This transformation was developed on furfuryl derivatives, using imines as directing groups, and trialkylsilanes or bis(trimethylsilyl)methylsilane as silylating agents, in the presence of a hydride scavenger. Subsequently, fluoride-mediated activation strategies were applied to the C3−SiMe(OSiMe3)2 furfural derivatives to achieve a wide range of transformations of the C3−Si bond. Arylation, alkenylation, alkynylation, allylation and alkylation, as well as halogenation and trifluoromethylation were achieved in modest to high yields. A variety of high value-added products were thus easily obtained from the same common C3-silylated furfural-based platform.
    Mots-clés : Biomass, Fluoride, Furfural, Iridium, POLE 1, ROCS, Silicon.

  • S. Curpanen, P. Reichert, G. Lupidi, G. Poli, J. Oble, et A. Perez-Luna, « Modular synthesis of 2-furyl carbinols from 3-benzyldimethylsilylfurfural platforms relying on oxygen-assisted C–Si bond functionalization », Beilstein Journal of Organic Chemistry, vol. 18, nᵒ 1, p. 1256-1263, sept. 2022.
    Résumé : Beilstein Journal of Organic Chemistry
    Mots-clés : POLE 1, ROCS.

  • S. De, A. Flambard, B. Xu, L. ‐M. Chamoreau, G. Gontard, L. Lisnard, Y. Li, M. ‐L. Boillot, et R. Lescouëzec, « Molecular Magnetic Materials Based on {Co <sup>III</sup> (Tp*)(CN) <sub>3</sub> } <sup>−</sup> Cyanidometallate: Combined Magnetic, Structural and <sup>59</sup> Co NMR Study », Chemistry – A European Journal, vol. 28, nᵒ 50, sept. 2022.

  • T. Deis, J. Forte, L. Fensterbank, et G. Lemière, « Synthesis and Reactivity of Martin’s Spirosilane-Derived Chloromethylsilicate », Molecules, vol. 27, nᵒ 6, p. 1767, janv. 2022.
    Résumé : Pentacoordinate silicon derivatives with a chloromethyl ligand are versatile compounds that are usually obtained from the corresponding tetravalent trialkoxy- or trihalogeno(chloromethyl)silane. We describe herein the synthesis of a chloromethylsilicate bearing two Martin’s ligands readily obtained by addition of in situ generated chloromethyllithium to a spirosilane. The reactivity of this new species was evaluated and it has been established that the chloride is displaced by strong nucleophiles such as alkyllithiums and (hetero)aryllithiums. In Lewis acidic conditions, the pentacoordinate silicon species rearranges through a formal insertion of a methylene into one Si–C bond, to form a new tetravalent spirosilane with a six-membered ring. The same kind of rearrangement can be triggered also by addition of a Lewis base. The mechanism of the rearrangement in both conditions has been studied by means of DFT calculations.
    Mots-clés : DFT calculations, MACO, pentacoordination, POLE 1, Sila-Matteson rearrangement, silicon, spirosilane.

  • T. Deis, J. Maury, F. Medici, M. Jean, J. Forte, N. Vanthuyne, L. Fensterbank, et G. Lemière, « Synthesis and Optical Resolution of Configurationally Stable Zwitterionic Pentacoordinate Silicon Derivatives », Angewandte Chemie International Edition, vol. 61, nᵒ 3, p. e202113836, 2022.
    Résumé : Stereogenic silicon centres in functionalised tetracoordinated organosilanes generally exhibit very high configurational stability under neutral conditions. This stability drops completely when higher coordination states of the silicon centre are reached due to rapid substituent exchange. Herein we describe the synthesis of chiral and neutral pentacoordinate silicon derivatives with high configurational stability. The zwitterionic nature of these air- and water-tolerant species allows for the first time their direct and efficient optical resolution using chiral HPLC techniques. By means of this method, pentacoordinate silicon compounds exhibiting high Si-inversion have been obtained as single enantiomers. A rationalisation of the enantiomerisation pathways has been also carried out using DFT calculations.
    Mots-clés : Chiral HPLC, Chirality, MACO, Optical resolution, POLE 1, Silicon, Zwitterion.

  • L. J. P. Dufour, A. M. Herrmann, J. Leloup, C. Przybylski, L. Foti, L. Abbadie, et N. Nunan, « Potential energetic return on investment positively correlated with overall soil microbial activity », Soil Biology and Biochemistry, vol. 173, p. 108800, 2022.

  • C. Fayolle, P. Pigeon, N. Fischer-Durand, M. Salmain, O. Buriez, A. Vessières, et E. Labbé, « Synthesis, Electrochemical and Fluorescence Properties of the First Fluorescent Member of the Ferrocifen Family and of Its Oxidized Derivatives », Molecules, vol. 27, nᵒ 19, p. 6690, 2022.
    Résumé : The first fluorescent ferrociphenol derivative (P797) has been synthesized via McMurry cross-coupling followed by copper-catalyzed [3 + 2] azide-alkyne cycloaddition of the fluorescent group coumarin. Cyclic voltammograms of P797 exhibit either a monoelectronic oxidation wave ascribed to the ferrocene Fe(II) → Fe(III) conversion or a three-electron oxidation process in the presence of a base, leading to a Fe(III) quinone methide adduct. This general sequence is consistent with those previously described for non-fluorescent ferrociphenols. Furthermore, the fluorescence properties of P797 and its oxidized intermediates appear to strongly depend on the redox state of the ferrocene group. Indeed,

    electrochemical generation of Fe(III) (ferrocenium) states markedly increases the fluorescence emission intensity. In contrast, the emission of the Fe(II) (ferrocene) states is partially quenched by photoinduced electron transfer (PET) from the Fe(II) donor to the coumarin acceptor and by concentration-dependent self-quenching. Owing to its switchable fluorescence properties, complex P797 could represent an innovative and useful tool to study the biodistribution and the redox state of ferrocifens in cancer cells.
    Mots-clés : CHEMBIO, coumarin, ferrocene, fluorescence switching, PET, POLE 3, redox state.
    Note Note

  • S. Gahlot, A. Gradone, M. Roy, M. Giorgi, S. Conti, P. Ceroni, M. Villa, et M. Gingras, « Persulfurated Benzene-Cored Asterisks with π-Extended ThioNaphthyl Arms: Synthesis, Structural, Photophysical and Covalent Dynamic Properties », Chemistry – A European Journal, vol. 28, nᵒ 46, p. e202200797, 2022.
    Résumé : The synthesis of regioisomeric asterisks (5) and (6) incorporating a benzene core with six 1-naphthylthio or six 2-naphthylthio arms are reported in search for new materials with optoelectronic properties. The consequences on the extension of a π system surrounding a persulfurated benzene core provide a new avenue to study the structural, photophysical, and chemical properties of such family of all-organic phosphors. It also diverts the persulfuration mechanism after two radical cyclizations for making a [5]dithiohelicene by-product (7) and favors dynamic sulfur component exchange reactions surrounding the core. These exchanges convert asterisks (5) and (6), non-phosphorescent at 20 °C to the highly phosphorescent (4) (ϕ ∼100 %, solid state at 20 °C). For asterisks (5) and (6), the absence of the typical phosphorescence of the per(phenylthio)benzene core in the solid state at 20 °C and the presence of a weak naphthalene-based phosphorescence at 77 K is attributed to an energy transfer from the triplet state of the persulfurated benzene core to the outer naphthalene moieties, resulting in an antenna system.
    Mots-clés : arenes, aromatic substitution, materials science, photophysics, POLE 1, ROCS, sulfur, supramolecular chemistry.

  • J. Glatz, J. - R. Jiménez, L. Godeffroy, H. J. von Bardeleben, L. Fillaud, E. Maisonhaute, Y. Li, L. - M. Chamoreau, et R. Lescouëzec, « Enlightening the Alkali Ion Role in the Photomagnetic Effect of FeCo Prussian Blue Analogues », Journal of the American Chemical Society, vol. 144, nᵒ 24, p. 10888-10901, juin 2022.

  • M. S. M. Holmsen, C. Blons, A. Amgoune, M. Regnacq, D. Lesage, E. D. Sosa Carrizo, P. Lavedan, Y. Gimbert, K. Miqueu, et D. Bourissou, « Mechanism of Alkyne Hydroarylation Catalyzed by (P,C)-Cyclometalated Au(III) Complexes », Journal of the American Chemical Society, vol. 144, nᵒ 49, p. 22722-22733, déc. 2022.

  • A. Hueber, Y. Gimbert, G. Langevin, J. - M. Galano, A. Guy, T. Durand, N. Cenac, J. Bertrand-Michel, et J. - C. Tabet, « Identification of bacterial lipo-amino acids: origin of regenerated fatty acid carboxylate from dissociation of lipo-glutamate anion », Amino Acids, vol. 54, nᵒ 2, p. 241-250, 2022.
    Résumé : Abstract The identification of bacterial metabolites produced by the microbiota is a key point to understand its role in human health. Among them, lipo-amino acids (LpAA), which are able to cross the epithelial barrier and to act on the host, are poorly identified. Structural elucidation of few of them was performed by high-resolution tandem mass spectrometry based on electrospray combined with selective ion dissociations reach by collision-induced dissociation (CID). The negative ions were used for their advantages of yielding only few fragment ions sufficient to specify each part of LpAA with sensitivity. To find specific processes that help structural assignment, the negative ion dissociations have been scrutinized for an LpAA: the N -palmitoyl acyl group linked to glutamic acid (C16Glu). The singular behavior of [C16Glu-H]¯ towards CID showed tenth product ions, eight were described by expected fragment ions. In contrast, instead of the expected product ions due to CONH-CH bond cleavage, an abundant complementary dehydrated glutamic acid and fatty acid anion pair were observed. Specific to glutamic moiety, they were formed by a stepwise dissociation via molecular isomerization through ion–dipole formation prior to dissociation. This complex dissociated by partner splitting either directly or after inter-partner proton transfer. By this pathway, surprising regeneration of deprotonated fatty acid takes place. Such regeneration is comparable to that occurred from dissociation to peptides containing acid amino-acid. Modeling allow to confirm the proposed mechanisms explaining the unexpected behavior of this glutamate conjugate.
    Mots-clés : CSOB, POLE 3.

  • A. Hueber, M. Green, J. Ujma, K. Richardson, Y. Gimbert, N. Cenac, J. Bertrand-Michel, et J. - C. Tabet, « Energy-Resolved Ion Mobility Spectrometry: Composite Breakdown Curves for Distinguishing Isomeric Product Ions », Journal of the American Society for Mass Spectrometry, vol. 34, nᵒ 1, p. 36-47, déc. 2022.

  • A. Hueber, C. Petitfils, P. Le Faouder, G. Langevin, A. Guy, J. - M. Galano, T. Durand, J. - F. Martin, J. - C. Tabet, N. Cenac, et J. Bertrand-Michel, « Discovery and quantification of lipoamino acids in bacteria », Analytica Chimica Acta, vol. 1193, p. 339316, 2022.

  • C. Huez, D. Guérin, S. Lenfant, F. Volatron, M. Calame, M. L. Perrin, A. Proust, et D. Vuillaume, « Redox-controlled conductance of polyoxometalate molecular junctions », Nanoscale, vol. 14, nᵒ 37, p. 13790-13800, sept. 2022.
    Résumé : We demonstrate the reversible in situ photoreduction of molecular junctions of a phosphomolybdate [PMo12O40]3− monolayer self-assembled on flat gold electrodes, connected by the tip of a conductive atomic force microscope. The conductance of the one electron reduced [PMo12O40]4− molecular junction is increased by ∼10, and this open-shell state is stable in the junction in air at room temperature. The analysis of a large current–voltage dataset by unsupervised machine learning and clustering algorithms reveals that the electron transport in the pristine phosphomolybdate junctions leads to symmetric current–voltage curves, controlled by the lowest unoccupied molecular orbital (LUMO) at 0.6–0.7 eV above the Fermi energy with ∼25% of the junctions having a better electronic coupling to the electrodes than the main part of the dataset. This analysis also shows that a small fraction (∼18% of the dataset) of the molecules is already reduced. The UV light in situ photoreduced phosphomolybdate junctions systematically feature slightly asymmetric current–voltage behaviors, which is ascribed to the electron transport mediated by the single occupied molecular orbital (SOMO) nearly at resonance with the Fermi energy of the electrodes and by a closely located single unoccupied molecular orbital (SUMO) at ∼0.3 eV above the SOMO with a weak electronic coupling to the electrodes (∼50% of the dataset) or at ∼0.4 eV but with a better electrode coupling (∼50% of the dataset). These results shed light on the electronic properties of reversible switchable redox polyoxometalates, a key point for potential applications in nanoelectronic devices.
    Mots-clés : E-POM, POLE 2.

  • S. Hupin, V. Tognetti, F. Rosu, S. Renaudineau, A. Proust, G. Izzet, V. Gabelica, C. Afonso, et H. Lavanant, « Lennard-Jones interaction parameters of Mo and W in He and N2 from collision cross-sections of Lindqvist and Keggin polyoxometalate anions », Physical Chemistry Chemical Physics, vol. 24, nᵒ 26, p. 16156-16166, juill. 2022.
    Résumé : Drift tube ion mobility spectrometry (DTIMS) coupled with mass spectrometry was used to determine the collision cross-sections (DTCCS) of polyoxometalate anions in helium and nitrogen. As the geometry of the ion, more than its mass, determines the collision cross-section with a given drift gas molecule, we found that both Lindqvist ions Mo6O192− and W6O192− had a DTCCSHe value of 103 ± 2 Å2, and both Keggin ions PMo12O403− and PW12O403− had a DTCCSHe value of 170 ± 2 Å2. Similarly, ion mobility experiments in N2 led to DTCCSN2 values of 223 ± 2 Å2 and 339 ± 4 Å2 for Lindqvist and Keggin anions, respectively. Using optimized structures and partial charges determined from dens

    ity functional theory calculations, followed by CCS calculations via the trajectory method, we determined Lennard-Jones 6-12 potential parameters ε, σ of 5.60 meV, 3.50 Å and 3.75 meV, 4.40 Å for both Mo and W atoms interacting with He and N2, respectively. These parameters reproduced the CCS of polyoxometalates within 2% accuracy.
    Mots-clés : E-POM, POLE 2.

  • P. Idlas, A. Ladaycia, F. Némati, E. Lepeltier, P. Pigeon, G. Jaouen, D. Decaudin, et C. Passirani, « Ferrocifen stealth LNCs and conventional chemotherapy: a promising combination against multidrug-resistant ovarian adenocarcinoma », International Journal of Pharmaceutics, p. 122164, sept. 2022.
    Résumé : Ovarian cancer is one of the deadliest epithelial malignancies in women, owing to the multidrug resistance that restricts the success of conventional chemotherapy, carboplatin and paclitaxel. High grade serous ovarian carcinoma can be classified into two subtypes, the chemosensitive High OXPHOS and the Low OXPHOS tumour, less sensitive to chemotherapy. This difference of treatment efficacy could be explained by the redox status of these tumours, High OXPHOS exhibiting a chronic oxidative stress and an accumulation of reactive oxygen species. Ferrocifens, bio-organometallic compounds, are believed to be ROS producers with a good cytotoxicity on ovarian cancer cell lines. The aim of this study was to evaluate the in vivo efficacy of ferrocifen stealth lipid nanocapsules on High and Low OXPHOS ovarian Patient-Derived Xenograft models, alone or in combination to standard chemotherapy. Accordingly, two ferrocifens, P53 and P722, were encapsulated in stealth LNCs. The treatment by stealth P722-LNCs in combination with standard chemotherapy induced, with a concentration eight time lower than in stealth P53-LNCs, similar tumour reduction on a Low OXPHOS model, allowing us to conclude that P722 could be a leading ferrocifen to treat ovarian cancer. This combination of treatments may represent a promising synergistic approach to treat resistant ovarian adenocarcinoma.
    Mots-clés : CHEMBIO, Multidrug resistance, Nanoparticle, Organometallic compound, Ovarian cancer, Patient-Derived Xenograft model, POLE 3, ROS producer molecule.

  • T. Ishii, K. Miyata, M. Mamada, F. Bencheikh, F. Mathevet, K. Onda, S. Kéna-Cohen, et C. Adachi, « Low-Threshold Exciton-Polariton Condensation via Fast Polariton Relaxation in Organic Microcavities », Advanced Optical Materials, vol. 10, nᵒ 3, p. 2102034, 2022.
    Résumé : In organic microcavities, a macroscopic condensate of exciton-polaritons can be formed at high-exciton polariton densities. The threshold for forming this condensate is proportional to the relaxation rate from initially excited excitons to these polaritons and the lifetime of the lowest energy polariton states. Although the influence of the lower polariton (LP) lifetime on the threshold has been studied, the relationship between the polariton relaxation rate and the threshold has not been fully explored. In this study, a room-temperature polariton condensate is demonstrated at a threshold pump fluence of 9.7 ± 0.1 µJ cm−2, in a microcavity containing 4,4″-bis((E)-4-(3,6-bis(2-ethylhexyl)-(9H-carbazol-9-yl))styryl)-1,1″-biphenyl (BSBCz-EH). By using a semiclassical model to describe the polariton kinetics, it is revealed that this low threshold results from the rapid relaxation rate from the dark exciton reservoir to the set of the LP states forming the condensate, with an effective rate Wep ≈ 2.0 × 10−5 cm3 s−1. These results show that accelerating polariton relaxation is possible and is an important factor for realizing low-threshold polariton condensates.
    Mots-clés : low threshold, microcavities, organic semiconductors, polariton condensate, polariton relaxation, POLYMERES, strong coupling.

  • O. Jackowski et A. Perez-Luna, « Propargylsilanes (Update 2022) », in Science of Synthesis, 2022/3: Knowledge Updates 2022/3, 1st editionᵉʳ éd., Thieme Verlag, 2022.
    Résumé : Thieme E-Books & E-Journals
    Mots-clés : POLE 1, ROCS.

  • L. K/Bidi, A. Desjonquères, G. Izzet, et G. Guillemot, « H<sub>2</sub> Evolution at a Reduced Hybrid Polyoxometalate and Its Vanadium-Oxo Derivative Used as Molecular Models for Reducible Metal Oxides », Inorganic Chemistry, p. acs.inorgchem.2c01741, juill. 2022.

  • P. Kumar, A. Swain, J. Acharya, Y. Li, V. Kumar, G. Rajaraman, E. Colacio, et V. Chandrasekhar, « Synthesis, Structure, and Zero-Field SMM Behavior of Homometallic Dy2, Dy4, and Dy6 Complexes », Inorganic Chemistry, vol. 61, nᵒ 30, p. 11600-11621, août 2022.
    Résumé : The synthesis, structure, and magnetic properties of three DyIII complexes of different nuclearity, [Dy2(H2L)2(NO3)] [NO3]·2H2O·CH3OH (1), [Dy4(HL)2(piv)4(OH)2] (2), and [Dy6(H2L)3(μ3–OH)(μ3–CO3)3(CH3OH)4(H2O)8] 5Cl·3H2O (3) [(H4L) = 6-((bis(2-hydroxyethyl)amino)-N′-(2-hydroxybenzylidene)picolinohydrazide)], are described. This variety of complexes with the same ligand could be obtained by playing with the metal-to-ligand molar ratio, the type of DyIII salt, the kind of base, and the presence/absence of coligand. 1 is a dinuclear complex, while 2 is a tetranuclear assembly with a butterfly-shaped topology. 3 is a homometallic hexanuclear complex that exhibits a propeller-shaped topology. Interestingly, in this complex 3, three atmospheric carbon dioxide molecules are trapped in the form of carbonate ions, which assist in holding the hexanuclear complex together. All of the complexes reveal a slow relaxation of magnetization even in zero applied field. Complex 1 is a zero-field SMM with an effective energy barrier (Ueff) of magnetization reversal equal to 87(1) K and a relaxation time of τ0 = 6.4(3) × 10–9 s. Under an applied magnetic field of 0.1 T, these parameters change to Ueff = 101(3) K, τ0 = 2.5(1) × 10–9 s. Complex 2 shows zero-field SMM behavior with Ueff = 31(2) K, τ0 = 4.2(1) × 10–7 s or τ01 = 2(1) × 10–7 s, Ueff1 = 37(8) K, τ02 = 5(6) × 10–5 s, and Ueff2 = 8(4) by considering two Orbach relaxation processes, while 3, also a zero-field SMM, shows a double relaxation of magnetization [Ueff1 = 62.4(3) K, τ01 = 4.6(3) × 10–8 s, and Ueff1 = 2(1) K, τ02 = 4.6(2) × 10–5 s]. The ab initio calculations indicated that in these complexes, the Kramer’s ground doublet is characterized by an axial g-tensor with the prevalence of the mJ = ±15/2 component, as well as that due to the weak magnetic coupling between the metal centers, the magnetic relaxation, which is dominated by the single DyIII centers rather than by the exchange-coupled states, takes place via Raman/Orbach or TA-QTM. Moreover, theoretical calculations support a toroidal magnetic state for complex 2.
    Mots-clés : ERMMES, POLE 2.

  • M. Laurans, M. Mattera, R. Salles, L. K’Bidi, P. Gouzerh, S. Renaudineau, F. Volatron, G. Guillemot, S. Blanchard, G. Izzet, A. Solé-Daura, J. M. Poblet, et A. Proust, « When Identification of the Reduction Sites in Mixed Molybdenum/Tungsten Keggin-Type Polyoxometalate Hybrids Turns Out Tricky », Inorganic Chemistry, vol. 61, nᵒ 20, p. 7700-7709, mai 2022.

  • P. Le Bellec, P. Midoux, H. Cheradame, V. Bennevault, et P. Guégan, « Tuneable thermal properties of PTHF-based copolymers by incorporation of epoxide units », European Polymer Journal, vol. 168, p. 111096, avr. 2022.
    Résumé : In order to decrease the crystallinity of polytetrahydrofuran (PTHF), statistical copolymerizations with 1,2-butylene oxide (BO) and 3,3-dimethyl-1,2-butylene oxide (DMBO) epoxides as comonomer were investigated in a process compatible with an easy scaling up. Difunctionnal poly(tetrahydrofuran-stat-1,2-butylene oxide)s (PTHF-stat-PBO) and poly(tetrahydrofuran-stat-3,3-dimethyl-1,2-butylene oxide)s (PTHF-stat-PDMBO) were synthesized in the range of 0–20 °C using different operating conditions. The reactivity ratios showed a homogeneous distribution of the epoxide units all along the copolymer chains by using BO, while an alternation of several THF and DMBO monomer units sequences was obtained in the DMBO-based copolymers. Still, both copolymerizations fit well with an ideal copolymerization behavior. A slow addition of BO during the propagation step or the introduction of BO or DMBO at the beginning of the polymerization were investigated. Whatever the comonomer used, its insertion in the polymer chain reduced the melting temperature of the copolymers and the impact of the THF polymerization equilibrium on the yields. As a consequence, higher polymerization yields were obtained. A fairly good control of the polymer molar masses was observed, although elimination reactions were highlighted. However, operating conditions were determined to limit the content of the resulting alkene chain ends to about 10%, providing guaranties for further macromolecular architectures developments.
    Mots-clés : 2-Butylene oxide, 2-Butylene oxide3, 3-Dimethyl-1, Cationic ring-opening polymerization, Equilibrium, POLYMERES, Reactivity ratio, Tetrahydrofuran1, Thermal properties.

  • S. Le Luyer, P. Guégan, et N. Illy, « Episulfide Anionic Ring-Opening Polymerization Initiated by Alcohols and Primary Amines in the Presence of γ-Thiolactones », Macromolecules, vol. 55, nᵒ 13, p. 5430-5440, juill. 2022.
    Résumé : Among the sulfur-containing polymers, polythioethers remain very attractive structures due to their high sulfur atom content, making them interesting candidates for various industrial applications, for example, in the fields of energy storage or biomedical applications. Although anionic ring-opening polymerization of episulfides is known since decades, only a limited number of efficient initiating systems enable the synthesis of well-defined polymer chains. In this work, a one-pot, two-step method was developed in order to efficiently initiate the anionic ring-opening polymerization of propylene sulfide with alcohol or amine moieties using the latent thiol functionality of γ-thiolactones. First, the ring opening of γ-thiolactones with alcohols or amines was investigated in the presence of various bases (2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2-diazaphosphorine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 4-dimethylaminopyridine, tBuP1, and tBuP4). Then, the polymerization conditions were optimized, allowing the synthesis of well-defined α,ω-heterotelechelic poly(propylene sulfide)s with controlled molar mass up to 10 kg·mol–1 as evidenced by size-exclusion chromatography, 1H, 13C, and 2D NMR, and matrix-assisted laser desorption and ionization time-of-flight mass spectrometry. Depending on the initiating function (alcohol or amine), the initiator and the polythioether chains are connected either by an ester or by an amide bond. The stability of these bonds was studied under basic conditions.
    Mots-clés : POLYMERES.

  • A. Li, L. - M. Chamoreau, B. Baptiste, L. Delbes, Y. Li, F. Lloret, Y. Journaux, et L. Lisnard, « Solvothermal Synthesis, Temperature-Dependent Structural Study, and Magnetic Characterization of a Multipolydentate Oxamate-Based 2D Coordination Network », Crystal Growth & Design, vol. 22, nᵒ 12, p. 7518-7526, déc. 2022.
    Résumé : A multipolydentate N-substituted oxamate ligand bearing an additional carboxylato group has been successfully reacted in solvothermal conditions to form the 2D coordination network (TMA)3[CuMn(paba)2(OAc)]·8H2O (1). This coordination network displays a brick-wall type morphology with, thanks to the augmented connectivity of the ligand, a lower than usual metal ion nuclearity for the building subunit. Temperature-dependent structural studies indicate that the layered structure undergoes dehydration at 90 °C and remains stable up to 200 °C. Magnetic characterizations show that 1 behaves as a ferrimagnet, with a Curie temperature of 2.8 K.
    Mots-clés : ERMMES, POLE 2.

  • C. Loro, J. Oble, F. Foschi, M. Papis, E. M. Beccalli, S. Giofrè, G. Poli, et G. Broggini, « Acid-mediated decarboxylative C–H coupling between arenes and O-allyl carbamates », Organic Chemistry Frontiers, vol. 9, nᵒ 6, p. 1711-1718, mars 2022.
    Résumé : Treatment of O-allyl N-tosyl carbamates with aromatic compounds in the presence of Cu(OTf)2 or TMSOTf as promoters affords N-substituted 1-arylpropan-2-amines, 1,2-diarylpropanes, 1,1-diarylpropanes, or indanes, depending on the nature of the promoter and of the aryl substrates. A full mechanistic rational allowing appreciation of the outcome of these novel C–H based cascades is proposed. An initial acid promoted decarboxylative/deamidative Friedel–Crafts allylation takes place. After protonation of the allylated arene, evolution of the resulting cation may follow different paths depending on the nature of the arene partner and of the allyl moiety in the carbamate.
    Mots-clés : POLE 1, ROCS.

  • S. Mabrouk, H. Rinnert, L. Balan, J. Jasniewski, S. Blanchard, G. Medjahdi, R. Ben Chaabane, et R. Schneider, « Highly Luminescent and Photostable Core/Shell/Shell ZnSeS/Cu:ZnS/ZnS Quantum Dots Prepared via a Mild Aqueous Route », Nanomaterials, vol. 12, nᵒ 18, p. 3254, sept. 2022.
    Résumé : An aqueous-phase synthesis of 3-mercaptopropionic acid (3-MPA)-capped core/shell/shell ZnSeS/Cu:ZnS/ZnS QDs was developed. The influence of the Cu-dopant location on the photoluminescence (PL) emission intensity was investigated, and the results show that the introduction of the Cu dopant in the first ZnS shell leads to QDs exhibiting the highest PL quantum yield (25%). The influence of the Cu-loading in the dots on the PL emission was also studied, and a shift from blue–green to green was observed with the increase of the Cu doping from 1.25 to 7.5%. ZnSeS/Cu:ZnS/ZnS QDs exhibit an average diameter of 2.1 ± 0.3 nm and are stable for weeks in aqueous solution. Moreover, the dots were found to be photostable under the continuous illumination of an Hg–Xe lamp and in the presence of oxygen, indicating their high potential for applications such as sensing or bio-imaging.
    Mots-clés : E-POM, POLE 2.
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