Reaction of carboxylic acid esters with phenolates in oil-in-water microemulsions based on cetyltrimethylammonium bromide

A kinetic study of reactions of carboxylic acid esters with phenols activated with alkalis or amines in microemulsions based on cationic surfactants showed that the phenolates formed upon activation exhibit different nucleophilicity depending on the value of the negative charge on the oxygen atom, which is determined by the properties of the phenol, ionizing agent, and solvent.     

The micellar effect of the sodium bis(2-ethylhexyl)sulfosuccinate—decane—water reverse system on the hydrolysis of phosphonic acid esters

The reactivity of alkyl aryl chloromethylphosphonates in alkaline hydrolysis in the sodium bis(2-ethylhexyl)sulfosuccinate—decane—water reverse micellar system is mainly determined by the electronic properties of substituents and depends only slightly on their hydrophobicity. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1712–1715, October, 2000.     

Reaction of methyl 3-phenyl-3-chloro-2-oxopropionate with 2-mercapto- and 2-hydroxy-ethanolamines: The products and some of their transformations

It was found that the nature of the SH and OH groups in 2-mercapto- and 2-hydroxyethanolamines plays a decisive role in the reactions between these compounds and methyl 3-phenyl-3-chloro-2-oxopropionate, the products comprising 1,4-thiazine and 1,4-oxazane derivatives, respectively. Some of the reactions of these products were investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 250–252, February, 1993.     

Thiophene-2-aldehyde in the Darzens reaction

The reaction of the title compound with dichloroacetic acid esters in the presence of butyllithium gave esters of 3-thienyl-3-hydroxy-2,2-dichloropropionic acid.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center of the Russian Academy of Sciences, 420083 Kazan', Russia. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1870–1873, August, 1992.     

Dicationic surfactant based catalytic systems for alkaline hydrolysis of phosphonic acid esters

Use of aqueous micellar solutions of dicationic surfactants with the general formula [R(CH₃)₂N(CH₂)₆N(CH₃)₂R]²⁺2Br⁻ (R = n-C₁₀H₂₁ to n-C₁₆H₃₃) as the reaction medium for the alkaline hydrolysis of phosphonic acid esters has revealed a strong catalytic effect of the surfactants, which can increase the reaction rate by two orders of magnitude. This effect depends on the surfactant structure, shows itself at low surfactant concentrations, and is substrate-specific. The effect of the micelles on the phosphonate hydrolysis rate is largely determined by the hydrophobicity factor.     

Structure and Specific Heat of Disordered and Ordered Titanium Monoxide TiOy

The structure of disordered and ordered titanium monoxide containing structural vacancies in both sublattices was studied by Xray diffraction. The symmetry of the monoclinic Ti₅O₅ superstructure (space group C2/m) was analyzed. The type and channel of the TiO_y–Ti₅O₅ disorder–order transition was determined. The distribution functions of Ti and O atoms in the metal and nonmetal sublattices of titanium monoxide were calculated. The specific heats of TiO_y titanium monoxides (0.8< y< 1.27) were measured by differential scanning calorimetry for the disordered and ordered states in the range from 340 to 600 K. The dependences of the specific heat, enthalpy, and entropy on the composition and structure of TiO_y were found for the first time. A notable effect of the structural state on the specific heat was detected. In the indicated temperature range, the C _p (T) dependence is adequately described by a function that accounts for the Debye effect and the electronic specific heat.     

Catalytic Effect of Multicomponent Supramolecular Systems in Phosphoryl-Group Transfer Reactions

The catalytic effect of the cetyltrimethylammonium bromide–poly(ethylenimine)–water system in the hydrolysis reactions of phosphonic acid esters (an increase in the rate constant by three orders of magnitude) is due to the concentration of reactants in polymer–colloid complexes and changes in their microenvironments. The catalyst efficiency depends on the structures of substrates, surfactants, and polymers.     

Reaction of methyl 3-phenyl-3-chloro-2-oxopropionate with thiosemicarbazones

The reaction of methyl 3-phenyl-3-chloro-2-oxopropionate with thiosemicarbazones proceeds via the intermediate formation of methyl [S-(1-alkylideneisothiosemicarbazidyl)]-3-phenyl-2-oxopropionate hydrochlorides, which then cyclize to novel 4-methoxycarbonyl-5-phenyl-2-substituted thiazoles. Hydrolysis of the intermediate products and the thiazoles obtained therefrom with simultaneous distillation of the carbonyl compound affords 2-hydrazino-4-methoxy-carbonyl-5-phenylthiazole.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1422–1426, June, 1991.     

Effect of ATP and amino acids on the properties of cationic amphiphiles in solution and on the surface

Russian Chemical Bulletin - The interaction between a number of cationic surfactants bearing the head group with different structures (triallyl, morpholinium, including hydroxyethyl-substituted)...     

Supramolecular catalytic systems based on anionic amphiphiles and polyethyleneimine for hydrolytic cleavage of phosphorus ester bonds

Self-organization in individual and binary systems based on polyethyleneimine (PEI) and amphiphilic sulfonatocalix[4]resorcinarene was studied by conductometry, tensiometry, dynamic light scattering, and ¹H NMR spectroscopy. The critical concentrations of micelle formation and aggregate sizes were determined. The enhancement of the catalytic effect on the hydrolysis of O-ethyl O-p-nitrophenyl chloromethylphosphonate was shown in the following series of the systems: PEI-water < PEI—calixarene-water < PEI—calixarene—La^III—water. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 366–373, February, 2008.