Effect of hydrothermal treatment conditions on formation of nickel hydrogermanate with platy morphology

Study of the phase composition and morphology of products formed in a hydrothermal treatment of the Ni(OH)₂–GeO₂–H₂O system with Ni/Ge cation molar ratios of 1, 1.5, and 2 in water and in aqueous solutions of HCl and NaOH demonstrated that the hydrothermal treatment products are composed of particles with plate-like morphology and average plate thickness of 40 nm and width of 500 nm. In this case, the phase composition of the products depends both on the molar ratio between the Ni and Ge cations and on the composition of the hydrothermal medium. Single-phase samples with structure similar to that of lizardite were obtained by treatment of a mixture with Ni/Ge = 1 in an alkaline medium or in a mixture with Ni/Ge = 1.5, irrespective of the composition of the medium. With the excess of GeO₂, a talc-like phase is formed, whereas with the excess of Ni(OH)₂, the samples contain crystalline nickel hydroxide in addition to the lizardite-like phase. Possessing magnetic and semiconductor properties, the single-phase nanopowders obtained in the study are promising as functional nanodispersed fillers of composite materials.     

Study of the inhibiting activity of tocopherol

Conclusions Tocopherol possesses a high ability to react with peroxide radicals; the stoichiometric coefficient of inhibition is equal to 3.2. The conversion products of tocopherol also possess inhibiting properties; however, their activity is approximately 20 times lower than the activity of free tocopherol.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2714–2718, December, 1972.     

Unexpected Reaction of Secondary Phosphine Chalcogenides with Acridine

Secondary phosphine chalcogenides reacted with acridine under mild conditions according to the nucleophilic addition scheme to form 9-chalcogenophosphoryl-9,10-dihydroacridines.

     

Reaction of aryl(diarylphosphoryl)methanols with alkyl propiolates. Regio- and stereoselective synthesis of functional vinyl ethers

Aryl(diarylphosphoryl)methanols reacted with alkyl propiolates under mild conditions (triethylamine, THF, 22?25°C), to give the corresponding anti-Markovnikov adducts, alkyl (E)-3-[aryl(diarylphosphoryl) methoxy]prop-2-enoates, with high yields (84–90%) and regio- and stereoselectivity.     

Three-Component Reaction of 4-Methylpyridine with Alkyl Propiolates and Secondary Phosphine Chalcogenides

The reaction between 4-methylpyridine, alkyl propiolates, and secondary phosphine oxides proceeded as N-vinylation-C-phosphorylation with stereo- and regioselective formation of (E)-N-ethenyl-C²- phosphoryl-1,2-dihydropyridines [when using bis(2-phenylethyl)phosphine oxide] or (E)-N-ethenyl-C⁴- phosphoryl-1,4-dihydropyridines (when using diphenylphosphine oxide). The process occurred at 60–62°C within 3 h to give functional dihydropyridines in 40–82% yield. Under similar conditions, bis(2-phenylethyl) phosphine sulfide and selenide reacted with alkyl propiolates preferably by nucleophilic PH-monoaddition at the triple bond.     

Investigation of peculiarities of the composition and structure of methylalumoxanes:27Al and1H NMR spectra of trimethylaluminum and products of its incomplete hydrolysis

Trimethylaluminum and the methylalumoxanes produced by its incomplete (controlled) hydrolysis in various organic solvents have been investigated by²⁷Al and¹H NMR spectroscopy. Differences in the properties and spectral characteristics of methylalumoxanes obtained in toluene and pentane have been found.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1453–1457, August, 1993.     

Chlorination of secondary phosphine chalcogenides with carbon tetrachloride in the absence of bases

The interaction of bis(2-phenylethyl)phosphine sulfide, bis(2-phenylethyl)phosphine selenide and bis[2-(2-phenyl)propyl]phosphine selenide with carbon tetrachloride under heating (80°C, 8–20 h) leads to the formation of the corresponding chlorophosphine chalcogenides with the yield of 80–90%.

     

Expedient Route to Chalcogenophosphinates with Glucose Moieties via Todd–Atherton‐Like Coupling between Secondary Phosphine Chalcogenides and Diacetone‐d‐Glucose in the CCl4/Et3N System

Secondary phosphine chalcogenides react with diacetone‐d‐glucose (DAG) in the system CCl₄/Et₃N (70°C, 4–24 h) to afford DAG chalcogenophosphinates in up to 79% yield, thus paving a short way to optically active chalcogenophosphinates with glucose moieties. As an example, a mild regioselective hydrolysis (70°C, aqueous MeCOOH) of DAG bis(2‐phenylethyl)selenophosphinate) obtained leads to monoacetone‐d‐glucose bis(2‐phenylethyl)selenophosphinate.     

Oxidative coupling of hydroxy- or aminoazobenzenes with secondary phosphine chalcogenides: Towards new media-responsive molecular switches

One or two chalcogenophosphinate groups were introduced to the azobenzene scaffold via the oxidative cross-coupling reaction of 4-amino-, 4-hydroxy- and 4,4′-dihydroxyazobenzenes with secondary phosphine chalcogenides using the CCl₄/Et₃N system under mild conditions in 41–95% yield. Cis-trans photoisomerization of the phosphorylated azobenzenes was reversibly controlled by alternating UV/Vis light irradiation. The chalcogenophosphinate group imparts the properties of media-responsive molecular photoswitches to the synthesized azobenzenes.