A5004684676- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Crystallography and molecular interactions
- Organometallic Complex Synthesis and Catalysis
- Magnetism in coordination complexes
- Catalytic Cross-Coupling Reactions
- Organoboron and organosilicon chemistry
- Asymmetric Hydrogenation and Catalysis
- Lanthanide and Transition Metal Complexes
- Coordination Chemistry and Organometallics
- Synthesis and characterization of novel inorganic/organometallic compounds
- Catalytic C–H Functionalization Methods
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
- Organic and Molecular Conductors Research
- Porphyrin and Phthalocyanine Chemistry
- Synthetic Organic Chemistry Methods
- Synthesis and Properties of Aromatic Compounds
- Chemical Synthesis and Analysis
- Carbon dioxide utilization in catalysis
- Ferroelectric and Piezoelectric Materials
- Asymmetric Synthesis and Catalysis
- Supramolecular Chemistry and Complexes
- Inorganic Chemistry and Materials
- Metal complexes synthesis and properties
- Advanced NMR Techniques and Applications
Université de Rennes
2016-2025
Centre National de la Recherche Scientifique
2016-2025
Institut des Sciences Chimiques de Rennes
2016-2025
École Nationale Supérieure de Chimie de Rennes
2012-2022
Université Rennes 2
2018-2021
Institut National des Sciences Appliquées de Rennes
2018-2021
Institut de Physique de Rennes
2017-2021
Canadian Nautical Research Society
2018
Générale-Beaulieu Clinic
2015-2017
Bipar
2017
This study shows for the first time that rhombohedral to tetragonal phase transition in Na0.5Bi0.5TiO3 (NBT) is a two step transition. The transformation begins by order involving reconstructive of into an orthorhombic one, through formation intermediate modulated phase. slightly over 200 °C disappearance ferroelectric−ferroelastic domains. then formed from 230 300 °C, temperature at which it disappears. corresponds intergrowth perovskite blocks Pnma sheets are microtwinning process and...
NBT presents an orthorhombic to tetragonal second order phase transition that occurs near 320 °C. It corresponds the so-called antiferroelectric−paraelectric transition. A model is presented in which diffuse achieved by progressive canceling of antiphase octahedra tilting prevailing within a−b+a− structure, whereas in-phase maintained. This transformation gives finally rise a0a0c+ system phase. Electron diffraction experiments show a long-range ordering probably develops as P42/mnm ordered...
A very simple and inexpensive catalytic system based on abundant manganese as transition metal an phosphine-free bidendate ligand, 2-(aminomethyl)pyridine, has been developed for the reduction of a large variety carbonyl derivatives with 2-propanol hydrogen donor. Remarkably, reaction proceeds at room temperature low catalyst loading (down to 0.1 mol %) exhibits good tolerance toward functional groups. High TON (2000) TOF (3600 h–1) were obtained.
A fused π-helical N-heterocyclic carbene (NHC) system was prepared and examined through its diastereoisomerically pure cycloiridiated complexes. The latter display light-green phosphorescence with unusually long lifetimes circular polarization that depends on both the helical NHC P/M stereochemistry iridium Δ/Λ stereochemistry. These unprecedented features are attributed to extended π conjugation within carbenic ligand efficient helicene-NHC-Ir interaction.
On a direct course to the aldehyde: Hydrosilylation catalyzed by well-defined N-heterocyclic-carbene–iron complex under UV irradiation enabled selective reduction of esters aldehydes (see scheme; Bn=benzyl, Mes=mesityl). The low catalyst loading and very mild reaction conditions make this chemoselective transformation promising alternative with diisobutylaluminum hydride. Aldehydes are important building blocks used as reactive intermediates in organic total synthesis. Their preparation from...
A series of dialkylaluminum and -indium {ONR}MR′2 complexes (M = Al, R′ Me; M In, Me, CH2SiMe3) stabilized by a phenoxy-imine {ONR}− ligand platform, with variable R-imino substituents functionalized bulky o-SiPh3 in the phenoxy moiety, has been prepared structurally characterized solution solid state. {ONR}AlMe2 reacted alcohols, particular alkyl (S)-H-lactate, to generate corresponding {ONR}Al(OR)2 compounds. On other hand, indium {ONR}InR′2 proved largely inert toward alcohols. When they...
An efficient visible light induced rhodium(I)-catalyzed regioselective borylation of aromatic C-H bonds is reported. The photocatalytic system based on a single NHC-RhI complex capable both harvesting and enabling the bond breaking/forming at room temperature. chelating nature NHC-carboxylate ligand was critical to ensure stability RhI provide excellent activities. Experimental mechanistic studies evidenced photooxidative ortho addition upon irradiation with blue LEDs, leading cyclometalated...
Here we report the first experimental observation of magneto-chiral dichroism (MChD) detected through light absorption in an enantiopure lanthanide complex. The P and M enantiomers [YbIII((X)-L)(hfac)3] (X = P, M; L 3-(2-pyridyl)-4-aza[6]-helicene; hfac 1,1,1,5,5,5-hexafluoroacetylacetonate), where chirality is held by helicene-based ligand, were studied near-infrared spectral window. When irradiated with unpolarized a magnetic field, these chiral complexes exhibit strong MChD signal (gMChD...
Abstract A field‐induced chiral Yb III Single‐Molecule Magnet (SMM) displayed an unprecedented near‐infrared circularly polarized luminescence (NIR‐CPL) in the solid‐state. The bridging bis(1,10‐phenantro[5,6b])tetrathiafulvalene triad ( L ) allowed efficient sensitization of NIR 2 F 5/2 → 7/2 emission while NIR‐CPL is associated to f ‐ transitions ion bearing β‐diketonate derived‐camphorate ancillary ligands.
The combination of physical properties sensitive to molecular chirality in a single system allows the observation fascinating phenomena such as magneto-chiral dichroism (MChD) and circularly polarized luminescence (CPL) having potential applications for optical data readout display technology. Homochiral monodimensional coordination polymers Yb
The synthesis of enantiomerically pure aluminium, gallium and indium complexes supported by chiral (R,R)-((HH)ONNO(HH)) (1), (R,R)-((MeH)ONNO(HMe)) (2), (R,R)-((tButBu)ONNO(tButBu)) (3), (R,R)-((MeNO2)ONNO(MeNO2)) (4), (R,R)-((HOMe)ONNO(HOMe)) (5) (R,R)-((ClCl)ONNO(ClCl)) (6) (1,2)-diphenylethylene-salen ligands is described. Several these have been crystallographically authenticated, which highlights a diversity coordination patterns. Whereas all Ga form [Ga2(CH2SiMe3)4(ONNO)] bimetallic...
The reaction between the TTF-fused dipyrido[3,2-a:2',3'-c]phenazine (dppz) ligand (L) and 1 equiv of Ln(hfac)3·2H2O (hfac(-) = 1,1,1,5,5,5-hexafluoroacetyacetonate) or Ln(tta)3·2H2O (tta(-) 2-thenoyltrifluoroacetonate) (Ln(III) Dy(III) Yb(III)) metallic precursors leads to four mononuclear complexes formula [Ln(hfac)3(L)]·C6H14 (1), Yb(III) (2)) [Ln(tta)3(L)]·C6H14 (3), (4)), respectively. Their X-ray structures reveal that Ln(III) ion is coordinated bischelating nitrogenated coordination...
A new palladium complex series with N-heterocyclic carbene (NHC), pyridine and phosphine ligands, PdCl<sub>2</sub>(L)NHC (<bold>2a–c</bold>)(L = NHC), PdCl<sub>2</sub>(L<sup>1</sup>)NHC(<bold>3a–c</bold>)(L<sup>1</sup> pyridine), PdCl<sub>2</sub>(L<sup>2</sup>)NHC(<bold>4a–c</bold>)(L<sup>2</sup> triphenylphosphine) was synthesised fully characterized.
Abstract Manganese(I) catalysts incorporating readily available bidentate 2‐aminopyridinyl‐phosphine ligands achieve a high efficiency in the hydrogenation of carbonyl compounds, significantly better than parent ones based on more elaborated and expensive tridentate 2,6‐(diaminopyridinyl)‐diphosphine ligands. The reaction proceeds with low catalyst loading (0.5 mol%) under mild conditions (50 °C) yields up to 96%. magnified image
Manganese(I) complexes [(Cp(CH2)nNHCMes)Mn(CO)2] (2a, n = 1; 2b, 2) bearing Cp tethered NHC ligands have been prepared in good yield from [CpMn(CO)3] and N-mesitylimidazole as main components, using a novel synthetic strategy based on the anchoring of an imidazolium moiety to coordinated ligand, followed by intramolecular photochemical CO substitution for pendent generated situ upon addition base. The catalytic performances 2a–b hydrosilylation 2-acetonaphthone with Ph2SiH2 were found be...
Exsolution is a promising technique to design metal nanoparticles for electrocatalysis and renewable energy. In this work, Ni-doped perovskites, (Pr0.5Ba0.5)1–x/2Mn1–x/2Nix/2O3−δ with x = 0, 0.05, 0.1, 0.2 (S-PBMNx), were prepared exsolution systems as solid oxide fuel cell anodes catalysis applications. X-ray diffraction transmission electron microscopy (TEM) analyses demonstrated that correlating A-site deficiency Ni content can effectively induce of all under H2 atmosphere at T ∼ 875 °C,...
Several monometallic {LO(i)}M complexes of lithium (M = Li; i 1 (1), 2 (2), 3 (3)) or potassium K, (4)) and the heteroleptic bimetallic complex {LO(3)}Li·LiN(SiMe2H)2 (5), all supported by monoanionic aminoether-phenolate {LO(i)}(-) (i 1-3) ligands, have been synthesized structurally characterized. A large range coordination motifs is represented in solid state, depending on chelating ability ligand, size metal number metallic centres found complex. Pulse-gradient spin-echo NMR showed that...
A family of iron Knölker-type complexes bearing an N-heterocyclic carbene (NHC) ligand has been synthesized from the corresponding tricarbonyl(η4-cyclopentadienone)iron complex by reaction with in situ generated NHC ligand, under UV irradiation (350 nm) at room temperature. The six complexes, obtained good yields (64–84%) after purification on column chromatography, were fully characterized, including X-ray diffraction and electrochemical studies. activity these catalysis demonstrated for...
The tin(II) complexes {LO(x)}Sn(X) ({LO(x)}(-) =aminophenolate ancillary) containing amido (1-4), chloro (5), or lactyl (6) coligands (X) promote the ring-opening polymerization (ROP) of cyclic esters. Complex 6, which models first insertion L-lactide, initiates living ROP L-LA on its own, but derivatives 1-4 require addition alcohol to do so. Upon one ten equivalents iPrOH, precatalysts trimethylene carbonate (TMC); yet, hardly any activity is observed if tert-butyl (R)-lactate used instead...
Six benzimidazolium salts, having two nitrogen atoms substituted by various alkyl groups, have been synthesized in high yields. The salts readily converted into the corresponding PEPPSI‐type palladium–NHC complexes (PEPPSI = pyridine‐enhanced precatalyst preparation, stabilization, and initiation). structures of all compounds characterized 1 H NMR, 13 C IR spectroscopy, as well elemental analysis techniques, which support proposed structures. molecular structure one complex has determined...
The synthesis and characterization of new dicationic ruthenium iridium complexes bearing a dipyridylamine ligand (dpa) are reported. These display an unusual zwitterionic molecular structure in the solid state. complex [Cp*Ir(dpa)(OSO3)] (Ir1) was found to be very efficient base-free hydrogenation levulinic acid into γ-valerolactone (GVL). TONs as high 174000 have been obtained. We demonstrated that reduction LA GVL by transfer with formic is fact operating fed preliminary dehydrogenation. A...