Mendeleev Communications最新文献

Aluminate ionic liquid [Et₃NH]⁺[Al₂Cl₇]⁻ was found to be an effective catalyst for the reactions of haloadamantanes with trimethylsilyl azide to produce the corresponding azido- adamantanes in 92–98% yields. Using ‘click chemistry’, the thus obtained azidoadamantanes were reacted with terminal alkynes under thermal or microwave conditions to cleanly afford the expected 1,4-disubstituted 1,2,3-triazoles some of which were new.

It was found that small additives of E Te^IV species (< 1 at%) notably enhance the visible-light photocatalytic activity of polycrystalline anatase TiO₂. This effect can tentatively be attributed to the neutralization of the neighboring surface- located oxygen vacancy, acting as a recombination center for photogenerated holes and electrons, by the dopant stereochemically active lone electron pair E.

The reaction of 1,2,4,5-tetrakis(diphenylphosphinyl)benzene with Eu(ONO₂)₃∙6H₂O led to the formation of a new coordination polymer exhibiting a bright red glow when excited in a wide ultraviolet range (Qin = 19.9%).

Tris[(pyridin-4-yl)methyl]phosphine and its P-oxide, new promising ligands, were obtained based on the reaction between 4-[(trimethylsilyl)methyl]pyridine and PCl₃. The coordination properties of tris[(pyridin-4-yl)methyl]phosphine oxide (L) were exemplified by the synthesis of a braided-shaped chain polymer [Cu₄I₄L₂] showing green luminescence at ambient temperature.

The temperature dependence of dynamic viscosity was calculated on the basis of a new cluster-association equation, which was derived within the framework of the concept of chaotic particles. It was shown that the degree of cluster association naturally decreases with an increase in temperature, on average corresponding to the arrangement of three to four cluster particles in the association. For the first time, the values of the activation energy per monomer were obtained when assigning the activation energy to the average number of clusters.

It was shown for the first time that open microcapsules 1–5 µm in size with Mn₃O₄ walls and unique morphology are formed as a result of spraying an aqueous MnSO₄ solution onto the surface of an alkali solution. The walls have a thickness of 80–120 nm and consist of an array of Mn₃O₄ nanosheets with a thickness of 2–3 nm, oriented predominantly in the radial direction towards the center of the microcapsule. There is a special rim with a height of 100–200 nm around the hole of the most microcapsules, which can be a kind of ‘ground’ when fixing such microcapsules on the surface of a substrate in the process of application by the Langmuir–Schaefer technique.

Chalcogen bonding-driven interaction of 1,2,5-chalcogena- diazoles with charged and neutral Lewis bases is discussed. It is highlighted that this interaction is a promising method for optically-detected recognition and sensing of the bases, and, at one, for the formation of otherwise challenging chemical bonds.

A precursor for the production of azo chromophores, viz. 2-hydroxy-3-(N-methyl-N-phenylamino)propyl methacrylate, was prepared and characterized. Its copolymerization with methyl methacrylate was carried out and the copolymerization constants were determined: for 2-hydroxy-3-(N-methyl-N-phenylamino) propyl methacrylate, r₁ = 0.50; for methyl methacrylate, r₂ = 0.93. The average block lengths of monomers of the same type depending on the composition of the copolymer were estimated.

The sequential adsorption of phenylalanine and salicylic acid on a carbon sorbent was studied. The influence of modification conditions, including the sorbent/solution volume ratio, amino acid concentration, temperature and pH, on the adsorption parameters of phenylalanine, as well as the physicochemical properties of the resulting carbon sorbent sample, was established. The effect of sequential adsorption of phenylalanine and salicylic acid on the physicochemical characteristics of sorbents is shown.

A novel derivative of 4-styryl-1,8-naphthalimide containing an N-arylazadithia-15-crown-5-ether moiety as a receptor exhibited a hypsochromic shift with simultaneous fluorescence quenching upon complexation with the mercury(II) cation. The compound is suggested as a selective fluorescent chemosensor for the detection of Hg²⁺ in aqueous solutions and in HEK 293 cells.