New Phosphonic Acid Functionalized, Regioregular Polythiophenes

ABSTRACT: Here we present the synthesis of both regioregular amphiphilic polythiophenes carrying a phosphonic acid on alternating side chains (8) and a regioregular polythiophene polyelectrolyte carrying a phosphonic acid side chain (14). We present the cation self-assembly and colorimetric changes of these regioregular polythiophenes carrying phosphonic acids. We also have explored the ability of these polymers to attempt to form SAMs with zirconium

Immobilization of Cryptophane Derivatives onto SiO 2 /Au and Au Substrates

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Enhanced catalyst recovery in an aqueous copper-free Sonogashira cross-coupling reaction

We report the synthesis of a superparamagnetic nanoparticle MNP (c-Fe2O3/polymer) supported dendritic catalyst based on a bulky electron-rich phosphine Pd(II) complex. The high reactivity of this catalyst is described in a copper-free Sonogashira C–C cross-coupling reaction in water, and the significant role of surfactant additives is highlighted in the recovery study

Immobilization of Cryptophane Derivatives onto γ-Fe 2 O 3 Core–Shell Magnetic Nanoparticles

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Dendron-Functionalized Core–Shell Superparamagnetic Nanoparticles: Magnetically Recoverable and Reusable Catalysts for Suzuki C-C Cross-Coupling Reactions

A metallodendron functionalized with dicyclohexyldiphosphino palladium complex was synthesized. The metallodendron was grafted onto core–shell superparamagnetic nanoparticles (g-Fe2O3/polymer, 200–500 nm) to give optimal catalytic reactivity in cross-coupling reactions. The grafted nanoparticles were used as recoverable and reusable catalysts for Suzuki C-C cross-coupling reactions. They showed remarkable reactivity towards iodoand bromoarenes under mild conditions, and unprecedented reactivity towards chloroarenes. On completion of the catalytic reaction, the catalysts were readily recovered by using a simple magnet to attract the superparamagnetic grafted nanoparticles. Catalysts were recovered more than 25 times with almost no discernable loss of reactivity

Efficient strategy to increase the surface functionalization of core-shell superparamagnetic nanoparticles using dendron grafting

Core-shell c-Fe2O3/polymer 300 nm superparamagnetic nanoparticles, grafted by fluorescent dendrons using a convergent approach, showed an increase in their surface functionalization compared to grafting using a linear analogue

Hydrosilylation of Azide-Containing Olefins as a Convenient Access to Azidoorganotrialkoxysilanes for Self-Assembled Monolayer Elaboration onto Silica by Spin Coating

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Interplay of Charge Transfer, Dimensionality, and Amide Hydrogen Bond Network Adaptability in TCNQF4 Complexes of EDO-TTF-CONH2 and EDT-TTF-CONH2

International audience[EDO-TTF-CONH2][TCNQF4], triclinic system, space group P-1, a=8.2479(12) Å, b=12.282(2) Å, c=12.6842(18) Å, α=113.850(17)°, β=106.420(17)°, γ=90.284(19)°, V=1116.8(4) Å3; and [EDT-TTF-CONH2]2[TCNQF4], triclinic system, space group P-1, a=6.5858(9) Å, b=11.699(2) Å, c=12.2281(18) Å, α=104.000(19)°, β=93.611(17)°, γ=98.279(19)°, V=899.9(3) Å3, whose π-donor molecules, (ethylenedioxo)-carbamoyltetrathiafulvalene and (ethylenedithio)-carbamoyltetrathiafulvalene, respectively, differ solely by the nature of the chalcogen atoms in their outer ethylene dichalcogeno bridge, yet form very different charge-transfer complexes with the same π-acceptor. [EDO-TTF-CONH2•+]2 [TCNQF4•−]2 is a diamagnetic insulating ionic salt with a three-dimensional rock-salt-type structure based on discrete dimers while in the semi-conducting mixed-valence complex, [EDT-TTF-CONH2]2•+[TCNQF4•−], the mixed-valence dimers aggregate into infinite chains interspersed within parallel rows of non-interacting radical anions. It is shown how the robust and adaptable supramolecular amide hydrogen bond tweezers-like motifs common to the two solids simply comply to the 3-to-1 dimensionality reduction upon substitution of O for S

Modulation of laccase catalysed oxidations at the surface of magnetic nanoparticles

International audienceWe explored the coupling of laccases to magnetic nanoparticles (MNPs) with different surface chemical coating. Two laccase variants offering two opposite and precise orientations of the substrate oxidation site were immobilised onto core-shell MNPs presenting either aliphatic aldehyde, aromatic aldehyde or azide functional groups at the particles surface. Oxidation capabilities of the six-resulting laccase-MNP hybrids were compared on ABTS and coniferyl alcohol. Herein, we show that the original interfaces created differ substantially in their reactivities with an amplitude from 1 to > 4 folds depending on the nature of the substrate. Taking enzyme orientation into account in the design of surface modification represents a way to introduce selectivity in laccase catalysed reactions