Synthesis and characterization of magnetite particles covered with α-trietoxysilil-polydimethylsiloxane

New silicon magnetite ferrofluids were prepared by dispersing siloxane-coated magnetite particles in polydimethylsiloxane with low or high molecular weights. Ferrofluids are stable colloidal dispersions of ultra fine covered magnetite particles, which may be selected for a specific application. We demonstrated new methods of stabilizing the magnetic particles by reacting the hydroxyl groups on the surface of magnetite particles with terminal ethoxy groups of polydimethylsiloxane, followed by their dispersion in silicon fluids. The new silicon ferrofluids were tested from the morphology, magnetic properties/losses, and rheological properties point of view.     

Novel Lanthanide (III) Complexes Derived from an Imidazole–Biphenyl–Carboxylate Ligand: Synthesis,Structure and Luminescence Properties

A series of neutral mononuclear lanthanide complexes [Ln(HL)₂(NO₃)₃] (Ln = La, Ce, Nd, Eu, Gd, Dy, Ho) with rigid bidentate ligand, HL (4′-(1H-imidazol-1-yl)biphenyl-4-carboxylic acid) were synthesized under solvothermal conditions. The coordination compounds have been characterized by infrared spectroscopy, thermogravimetry, powder X-ray diffraction and elemental analysis. According to X-ray diffraction, all the complexes are a series of isostructural compounds crystallized in the P2/n monoclinic space group. Additionally, solid-state luminescence measurements of all complexes show that [Eu(HL)₂(NO₃)₃] complex displays the characteristic emission peaks of Eu(III) ion at 593, 597, 615, and 651 nm.     

Nitrogen-Based Linkers with a Mesitylene Core: Synthesis and Characterization

Mesitylene was used as a core in seven new tritopic nitrogen containing linkers. Three of the linkers, each containing three nitrile groups, were obtained through Suzuki, Sonogashira and Heck-type coupling reactions. Next, these were converted to tetrazol-5-yl moieties by the cycloaddition of sodium azide to the nitrile functionalities. The last linker, containing three 1,2,3-triazol-4-yl moieties, was synthesized by the Huisgen cycloaddition of phenyl azide to the corresponding alkyne. The latter was obtained via a Corey–Fuchs reaction sequence from the previously reported formyl derivative. As the proof of concept for their potential in MOF design, one of the nitriles was used to build an Ag-based network.     

Synthesis,structure, and thermal properties of polyrotaxanes derived from β-cyclodextrin and polydimethylsiloxane

Supramolecular inclusion complexes, polyrotaxanes, of β-cyclodextrin with modified polydimethylsiloxane were prepared. The structure and thermal properties of these complexes were studied as influenced by the preparation conditions, component ratio, and molecular weight of the polymer.     

Structure and thermal properties of polyrotaxanes derived from γ-cyclodextrin and modified polydimethylsiloxane

Supramolecular inclusion complexes, polyrotaxanes, derived from γ-cyclodextrin and polydimethylsiloxane modified with terminal epoxy groups were studied. The dependence of the structure, morphology, and thermal properties of polyrotaxanes on the molecular weight of the linear polymer, molar ratio of γ-cyclodextrin and polymer, and presence of free γ-cyclodextrin in the complexes was examined.     

Synthesis,structure, computational modeling,and biological activity of two novel bimesitylene derivatives

Research on Chemical Intermediates - Tetrazole- and nitrile-containing bimesitylene derivatives with potential use in coordination chemistry were synthesized and characterized, and their structural...