Synthesis and structure of bis(tetraphenyl-λ5-stibanyl)-1,7-carborane-1,7-dicarboxylate

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Synthesis of chiral nopinane annelated 3-methyl-1-aryl-1H-pyrazolo[3,4-b]pyridines by condensation of pinocarvone oxime with 1-aryl-1H-pyrazol-5-amines

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One-pot two-step stannylation/Stille homocoupling of aryl bromides and iodides under solvent-free conditions

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Adsorption of lead(II), cadmium(II) and dysprosium(III) from aqueous solutions using mesoporous silica modified with phosphonic acid groups

The mesoporous silica samples with different concentrations of phosphonic acid groups on the surface were obtained by direct template synthesis. The block-copolymer Pluronic P123 was used as a template, and sodium meta-silicate with diethylphosphatoethyltriethoxysilane as precursors. According to the SAXS diffractograms, mesoporous silica samples have a p6mm hexagonal symmetry. In addition, we used sol–gel method to synthesize xerogel with the same groups for comparison. All samples possess high values of specific surface area 615–730?m²/g and sorption pore volume. FTIR and potentiometric titration methods were used to investigate the surface layer of these samples. Sorption properties of the samples with phosphonic acid groups were studied in respect to a row of metal cations, among which we focused on lead(II), cadmium(II), and dysprosium(III) cations.

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Germylene complexes of tungsten pentacarbonyls W(CO)5GeCl2 and W(CO)5GeW(CO)5: Electrochemical synthesis and quantum-chemical computations

Convenient synthetic route to prepare the germylene complexes of tungsten pentacarbonyls, W(CO)₅GeCl₂ and W(CO)₅GeW(CO)₅, electrochemically is developed. Combined quantum-chemical/IR spectroscopic approach is used for identification of the synthesized compounds. Good agreement between theoretical and experimental spectra can be regarded as one of the proofs of their supposed structures.     

Novel Naphthol‐Based Bicyclic Phosphonates

Condensation of naphthol‐1 and naphthol‐2 with 2‐ethoxyvinyphosphonic acid dichloroanhydride in boiling toluene in the presence of trifluoroacetic acid has resulted in high yields of unknown bicyclic phosphonates. Composition and structure of the products obtained were confirmed according to ¹H and ³¹P nuclear magnetic resonance, infrared spectroscopy, and X‐ray analysis.     

Copolymers of 2-Deoxy-2-Methacrylamido-D-Glucose with Aminoacrylates and Allylamine Hydrochloride

New polyvinylsaccharides containing primary or tertiary amino groups were synthesized by radical copolymerization of 2-deoxy-2-methacrylamido-D-glucose (MAG) with 2-(dimethylamino)ethyl methacrylate, 2-(diethylamino)ethyl methacrylate (DEAEM), or allylamine hydrochloride. The reactivity ratios of comonomers were determined. The effect of copolymer composition on the conformational properties of macromolecules was detected. For MAG-DEAEM copolymers with DEAEM unit content more than 60 mol-% the increase of degree of ionization causes conformational transition at α = 0.3 to 0.7 from compact polymer coil to loose coil due to the electrostatic repulsion of charged amino groups. The increase of MAG content in copolymers is accompanied by a decrease of their cytotoxicity.     

Novel 4-chloro-or-4-bromoresorcinol-based bicyclic phosphonates

Abstract

The reaction of 4-chloro- and 4-bromoresorcinol with 2-ethoxyvinylphosphonic acid dichloroanhydride has been investigated for the first time. It has been determined that the product of the reaction is the mixture of structural isomers of bicyclic phosphonates at the ratio of 9:1. The structure and composition of the compounds have been elucidated from ¹H, ³¹P, and ¹³C NMR spectroscopy, mass-spectrometry (MALDI-TOF), as well as elemental and X-ray analysis.     

Phosphorylation of oxyethylated resorcinol and calix[4]resorcinarene with P(III) acid amides

Abstract

Phosphorylation of 1,3-bis(2-hydroxyethoxy)benzene and octa(2-hydroxyethyl) calix[4]-resorcinarenes with P(III) acid amides and chloramides has been studied. It has been determined that the nature of phosphorous acid amides affects significantly the synthetic result of the reaction.