Article
Polymer Science
Hamid Reza Hedayati, Manounchehr Khorasani, Mostafa Ahmadi, Nicholas Ballard
Summary: In this study, well-defined and linear PVAc was synthesized using RAFT polymerization method, overcoming the difficulties in controlling molecular weight distribution during the hydrolysis of PVAc. This offers a potential route to the production of PVAc and PVA products with uniform properties.
Article
Chemistry, Inorganic & Nuclear
Hellen Videa, Antonio J. Martinez-Martinez
Summary: This study presents the first structural elucidation of unbound beta-diketiminate anions within caesium complexes. The beta-diketiminate caesium salts were synthesized and upon addition of Lewis donor ligands, free BDI- anions and donor-solvated Cs+ cations were observed. The liberated BDI- anions showed a remarkable cisoid-transoid exchange in solution.
DALTON TRANSACTIONS
(2023)
Article
Polymer Science
Paul Galanopoulo, Laura Sinniger, Noemie Gil, Didier Gigmes, Catherine Lefay, Yohann Guillaneuf, Maelle Lages, Julien Nicolas, Franck D'Agosto, Muriel Lansalot
Summary: Degradable poly(methyl methacrylate) (PMMA) particles were synthesized using radical emulsion polymerization in water, with a cyclic ketene acetal, 5,6-benzo-2-methylene-1,3-dioxepane (BMDO), as a co-monomer. The stability of BMDO in aqueous media and the degradation mechanism were studied to understand its use in emulsion and its incorporation into the copolymer chains. Stable latexes with varying amounts of BMDO inserted units (2-6.4 mol%) were obtained, and the resulting copolymer exhibited an average molar mass loss of 90% during degradation in a basic medium.
Article
Chemistry, Inorganic & Nuclear
Deepamali Dissanayake, Craig Forsyth, Dragoslav Vidovic
Summary: This research reports the synthesis and characterisation of several chiral aluminium compounds with oxazoline-containing beta-diketiminate type ligands. These chiral Lewis acid complexes, in combination with 1 equiv. of Na(BAr4Cl), were successfully used as catalysts in asymmetric Diels-Alder reactions between 1,3-cyclohexadiene and various chalcones. Increasing the steric demand of the ligands' achiral end resulted in improved enantioinduction for the cyclisation of 1,3-cyclohexadiene and chalcone. Furthermore, modifying the chiral end by introducing a tert-butyl group to the stereogenic center of the oxazoline fragment yielded the highest enantioselectivity value. The substrate scope was expanded to include several different dienophiles, generating enantiomeric excess values ranging from 24-68%.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Physical
Qinzhi Quan, Yucheng Zhao, Kaixuan Chen, Huyan Zhou, Chengda Zhou, Mao Chen
Summary: By developing an organic photoredox catalyst, controlled photo-controlled radical copolymerization of multiple PFVEs and unconjugated comonomers is achieved. This method has high reaction efficiency and can produce a variety of complex fluoropolymers.
Article
Chemistry, Inorganic & Nuclear
Kevin Huse, Christoph Woelper, Stephan Schulz
Summary: This study investigates the reactions of (R)nac(2)ZnEt (R = Mes, Dipp) and (16)Fnac(2)ZnEt with various anions, revealing different reaction pathways and product formations. The research also shows that the Lewis acidity of [(16)Fnac(2)Zn][SbF6] is slightly lower compared to B(C6F5)(3) according to the Gutmann-Beckett method.
Article
Chemistry, Multidisciplinary
Wachara Benchaphanthawee, Chi-How Peng
Summary: Cobalt mediated radical polymerization (CMRP) plays a crucial role in controlling the polymerization of less active monomers, such as vinyl acetate, with the control mechanisms being correlated to the redox potential of cobalt complexes. The hybridization of CMRP and atom transfer radical polymerization (ATRP) allows for the direct synthesis of block copolymers in one pot. CMRP also enables the control of isotacticities and crystalline properties in polymers.
Article
Chemistry, Inorganic & Nuclear
Fen You, Suting Xu, Jixing Wang, Jingjing Zhai, Fei Wang, Li Pan, Yat-Ming So, Xiaochao Shi
Summary: A simple method for accessing new derivatizable bulky-demanding OHF ligands has been developed, leading to the synthesis of a series of half-sandwich rare-earth metal complexes bearing the OHF ancillary ligands, which exhibit high catalytic activity for styrene (co)polymerization.
INORGANIC CHEMISTRY
(2022)
Article
Polymer Science
Pei Li, Hongju Liu, Wanlu Tian, Zhanshan Ma, Xiaoyue Wang, Guoyong Xu, Chao Li, Muhammad Qasim, Fuzhou Wang
Summary: Improvement of amide derived catalysts used in olefin polymerization was achieved by synthesizing cationic nickel catalysts with steric and electronic factors variation. These bulky nickel catalysts showed significantly higher activity and thermal stability compared to previous open pyridine carboxamidate nickel catalysts. They produced higher molecular weight semi-crystalline polyethylene with tunable branching densities and melting points. Additionally, they also promoted the copolymerization of ethylene and methyl 10-undecenoate to yield functionalized polyethylenes with high incorporation rate of MU.
Article
Chemistry, Inorganic & Nuclear
Philipp Rinke, Helmar Goerls, Robert Kretschmer
Summary: The metalation of bis(beta-diketimine) ligands with flexible bridging groups using calcium and magnesium precursors resulted in the formation of various homoleptic and heteroleptic complexes, highlighting the distinct tendencies of calcium and magnesium in complex formation. Additionally, a rare trinuclear mixed heteroleptic-homoleptic magnesium complex was isolated, which serves as an intermediate of the Schlenk equilibrium.
INORGANIC CHEMISTRY
(2021)
Article
Polymer Science
Chujuan Huang, Toyoko Suzuki, Hideto Minami
Summary: In this study, micrometer-sized block copolymer particles were successfully synthesized using iodine transfer polymerization as a first attempt. Methyl methacrylate (MMA) and vinyl acetate (VAc) were used as the hydrophilic monomers in a microsuspension system. The resulting poly(methyl methacrylate)-block-poly(vinyl acetate) (PMMA-b-PVAc) particles exhibited the desired molecular weight and relatively narrow molecular weight distribution, despite the low degree of polymerization of the PVAc block. The hydrolysis of these particles resulted in three different morphologies, and the formation mechanism of each morphology was proposed, attributing it to the interaction between the iodic ions generated from the degradation of iodine end groups and the elongated poly(vinyl alcohol) (PVA) segments derived from PVAc.
Article
Chemistry, Inorganic & Nuclear
Bappaditya Goswami, Manas Khatua, Subhas Samanta
Summary: In this study, four Co(II) complexes were synthesized and characterized using various techniques. Their catalytic activity in styrene polymerization was evaluated, with complex 3 showing the highest efficiency among the azo-aromatic complexes, while the imine-based complex 4 exhibited lower activity.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Helge-Boj Hansen, Hubert Wadepohl, Markus Enders
Summary: The donor strength of bifunctional pyridine-cyclopentadienyl ligands can be altered by introducing donating groups, leading to higher catalytic activities in chromium complexes. Incorporating electron-donating groups efficiently transfers electronic influences to the metal center, resulting in ultra-high molecular weight polymers with high co-monomer incorporation ability.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Polymer Science
Liang Fang, Chun-Yu Zhang, Xue-Quan Zhang, Xian-De Shen, Heng Liu, Toyoji Kakuchi
Summary: In this study, it was unexpectedly found that the solubility of insoluble polynorbornene (PNB) products can be significantly improved by incorporating specific ligands, allowing for detailed analysis of the polymer products. It was also observed that high-temperature polymerization improves the solubility of PNB.
CHINESE JOURNAL OF POLYMER SCIENCE
(2023)
Article
Engineering, Chemical
Xiuqin Dong, Jiaqi Li, Jie Cheng, Yingzhe Yu
Summary: Vinyl acetate-ethylene copolymer is an important chemical product formed by the polymerization of vinyl acetate and ethylene. The lack of kinetic parameters makes the reactions involved in the production process complex. By using Density Functional Theory, molecular models were constructed to understand the polymerization process. The research found that batch operation is more suitable for complete conversion, while continuous operation is advantageous for synthesizing products with stable quality.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Dimitri Berne, Sebastien Lemouzy, Pascale Guiffrey, Sylvain Caillol, Vincent Ladmiral, Eric Manoury, Rinaldo Poli, Eric Leclerc
Summary: This study describes a spontaneous (uncatalyzed) Michael addition of thiols to alpha-trifluoromethyl acrylates and its efficient application in the preparation of a thermoset. Mechanistic investigation reveals a probable solvent-assisted proton transfer in the rate-determining step and a considerable lowering of the energy barrier induced by the CF3 group in the addition of arene- and alkanethiols to tert-butyl trifluoromethyl acrylate in polar aprotic solvents.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Maxime Michelas, Yasmine K. Redjel, Meriem Benslimane, Rinaldo Poli, Christophe Fliedel
Summary: This study reports the synthesis and characterization of cobalt(II) and acetato cobalt(III) complexes with tripodal tetradentate diamino-bis(phenolate) ligands. The structures of the proligand and complexes were determined by X-ray crystallography. The complexes exhibited different coordination modes and were not efficient initiators or moderators for radical polymerization reactions.
INORGANICA CHIMICA ACTA
(2023)
Article
Chemistry, Multidisciplinary
Julian Sobieski, Illia Ruzhylo, Grzegorz Szczepaniak, Adam Gorczynski, Krzysztof Matyjaszewski, Eric Manoury, Rinaldo Poli
Summary: Simple synthetic routes for the regioselective deuteration of tris[2-(dimethylamino)ethyl]amine (Me6TREN) variants are described. Formation of imine with formaldehyde-d(2) from tris(2-aminoethyl)amine (TREN) and subsequent reduction with NaBD4 resulted in N[CH2CH2N(CD3)(2)](3) or d(18)-Me6TREN in 79% yield. A trisubstitution protocol from 2-bromo-N,N-dimethylacetamide and ammonium carbonate, followed by reduction of the N(CH2CONMe2)(3) intermediate with lithium aluminum deuteride, afforded N[CH2CD2N(CH3)(2)](3) or (d(6)-arm)-Me6TREN in three steps and 52% overall yield. A similar protocol using 2-bromo-N,N-dimethyl-d(2)-acetamide, obtained from d(4)-acetic acid in two steps, and reduction of the N(CD2CONMe2)(3) intermediate with lithium aluminum hydride, resulted in N[CD2CH2N(CH3)(2)](3) or (d(6)-cap)-Me6TREN in four steps and 13% overall yield.
Article
Polymer Science
Jirong Wang, Chi Zhang, Yong Zhang, Gong Chen, Rinaldo Poli, Xiaolin Xie, Zhigang Xue
Summary: A simple aza-Michael addition method induced by lithium salts is used to design and fabricate high-performance polymer electrolytes with a more amorphous cross-linked structure. The in situ-constructed gel polymer electrolyte exhibits high ionic conductivity and excellent interface stability with the electrodes, leading to a LiFePO4 battery with high initial specific discharge capacity and good rate performance.
Article
Materials Science, Multidisciplinary
Guillaume Carnide, Laura Cacot, Yohan Champouret, Vincent Pozsgay, Thomas Verdier, Adele Girardeau, Marjorie Cavarroc, Andranik Sarkissian, Anne-Francoise Mingotaud, Constantin Vahlas, Myrtil Louise Kahn, Nicolas Naude, Luc Stafford, Richard Clergereaux
Summary: The Direct Liquid Reactor-Injector (DLRI) method has been used to achieve the requirements of nanocomposite thin films with non-aggregated nanoparticles uniformly dispersed in the matrix. Unlike traditional aerosol-assisted plasma deposition, the nanoparticles are synthesized into aerosols before being injected into plasma. Two different plasma reactors, a low-pressure RF plasma reactor and an atmospheric pressure parallel plate dielectric barrier discharge, were used in our experiments. The results show that DLRI can be easily coupled with various plasma processes to deposit high-quality multifunctional nanocomposite thin films with nanoparticles smaller than 10 nm in diameter, meeting the specifications for multifunctional coatings.
Article
Chemistry, Multidisciplinary
Abdelhak Lachguar, Uchchhal Bandyopadhyay, Mehdi Ech-Chariy, Sandrine Vincendeau, Catherine Audin, Jean-Claude Daran, Eric Manoury, Rinaldo Poli, Eric Deydier
Summary: This study presents a new solvent-less reaction method to convert benzylic, allylic, ferrocenyl or tertiary alcohols into S-thioesters, which are stable precursors of corresponding thiols. The reaction involves reactions in neat thioacetic acid in the presence of tetrafluoroboric acid, and increasing the HBF4 concentration can enhance the reaction rate. Control experiments and DFT calculations provide insights into the mechanism of the reaction and the formation of intermediate products.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Review
Chemistry, Inorganic & Nuclear
Meenu Murali, Eric Manoury, Rinaldo Poli
Summary: This review introduces various types of CooANs according to the nature of the metal-binding functions and discusses the mechanism of crosslink migration. CooANs can be obtained by the combination of ligand-functionalized polymers and metal ions or clusters, with crosslink migration occurring through ligand exchange with available free ligands in the polymer matrix.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Polymer Science
Dimitri Berne, Rinaldo Poli, Sylvain Caillol, Vincent Ladmiral, Eric Leclerc
Summary: This study develops a series of catalyst-free covalent adaptable networks (CANs) using a reversible thia-Michael reaction. By modulating the structure and functionality of the thiol monomers, a wide range of mechanical and thermal properties are achieved. The study also highlights the relationship between monomer structure and dynamic properties, and evaluates the reprocessing capability of the materials.
Article
Polymer Science
Julian Sobieski, Sajjad Dadashi Silab, Lucas Thevenin, Krzysztof Matyjaszewski, Christophe Fliedel, Rinaldo Poli
Summary: The termination processes of the tertiary carbomethoxyisopropylradical, (COOMe)Me2C & BULL;, were investigated by H-1 NMR. The investigation assessed the contributions of the Cu-I/L-catalyzed radical termination (CRT) and the reductive radical termination (RRT) to the spontaneous bimolecular radical terminations (RT). It also reassessed the product distribution for the RT of the diffused and caged radicals obtained from the thermal activation of V-601.
Article
Chemistry, Inorganic & Nuclear
Rinaldo Poli, Dung Nguyen, Yu-Sheng Liu, Eva Harth
Summary: This work investigated the thermal switchability of ethylene coordination/insertion to controlled radical polymerization of methyl acrylate using Brookhart-type α-diimine Pd-II catalysts. The impact of bulky α-diimine N-substituents was explored, revealing the reversible activation of the Pd-II-C bond and trapping during radical MA polymerization. DFT calculations evaluated the sterics effect on the stability of PE-MA-Pd-II chain-end structures and the bond dissociation-free energy for Pd(II)-C bond cleavage. Experimental investigations showed the failure of the Pd-II system to control radical polymerization of MA through OMRP mechanism.
Article
Chemistry, Inorganic & Nuclear
Ambra Maria Fiore, Valentina Petrelli, Christophe Fliedel, Eric Manoury, Piero Mastrorilli, Rinaldo Poli
Summary: The solution behavior of complex [Rh(COD)(& mu;-OAc)](2) in dichloromethane has been investigated in the absence and presence of PPN+OAc- using multinuclear NMR spectroscopy. The addition of PPN+OAc- results in the generation of [Rh(COD)(OAc)(2)](-) through equilibration. Rapid exchange between different Rh complexes and acetate ligands is observed at room temperature, but freezing the exchange at lower temperatures allows for the coalescence of certain NMR resonances.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Maxime Michelas, Jean-Claude Daran, Alix Sournia-Saquet, Christophe Fliedel, Rinaldo Poli
Summary: The addition of benzoyl peroxide to [Co-II(acac)(2)] selectively produces [Co-III(acac)(2)(O2CPh)], a mononuclear Co-III complex with an octahedral coordination geometry. This compound can serve as a thermal initiator for radical polymerisation. Addition of ligands (L = py, NEt3) induces chelate ring opening and formation of different isomers. The addition of py strengthens the Co-III-O2CPh bond and lowers the initiator efficiency, while the addition of NEt3 quenches the benzoate radical.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Illia Ruzhylo, Sandrine Vincendeau, Philippe Dauban, Eric Manoury, Rinaldo Poli, Agnes Labande
Summary: A series of heteroleptic dirhodium(ii) complexes have been evaluated for the redox-responsive decomposition of diazo substrates prone to chemoselectivity issues. The counter-anion of oxidized ferrocenyl-containing complexes was found to influence the chemoselectivity, with SbF6- and BAr4F- resulting in greater differences compared to BF4-. The correlation between ferrocenyl substituents and chemoselectivity switch was not obvious, but introducing a saturated tether drastically decreased the difference. Changing the electronic properties of only one ligand on dirhodium, by oxidation of its ferrocenyl part, had a marked influence on reaction selectivity.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Chantal J. Abou-Fayssal, Christophe Fliedel, Rinaldo Poli, Anders Riisager, Karine Philippot, Eric Manoury
Summary: This study introduces a method to improve the confinement of rhodium nanoparticles (RhNPs) in nanoreactors by introducing phosphine oxide as anchoring groups in the hydrophobic core of amphiphilic star-block copolymers. The RhNP-loaded latex exhibits excellent catalytic activity and recyclability, making it a promising candidate for aqueous biphasic catalysis.
MATERIALS TODAY CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Pardeep Dahiya, Nidhi Garg, Rinaldo Poli, Basker Sundararaju
Summary: To achieve the goal of a carbon-free energy economy, a well-defined air-stable Cp*Co(III) catalyst has been developed for the transfer hydrogenation of quinoline derivatives and the oxidative dehydrogenation of cyclic amines in water. These findings provide new avenues for studying environmentally benign cobalt catalysts for hydrogenation and dehydrogenation reactions.
DALTON TRANSACTIONS
(2023)
