Synthesis of oil-soluble multipurpose sulfonate additives based on low-molecular-weight alkylphenols

New multipurpose sulfonate additives improving the detergent, dispersant, anticorrosive, and antioxygenic properties of lubricant oils were developed on the basis of sulfomethylated alkyl(C₁₀–C₁₄)phenolformaldehyde condensation product.     

Hydroxyalkylbenzylsulfonates as multipurpose oil additives

New multipurpose additives of the sulfonate type improving detergency-dispersion, anticorrosive, and antioxygenic properties of lubricating oils were developed on the basis of sulfomethylated alkylphenol.     

Thermodynamic study of the Ag-As-Se and Ag-S-I systems using the EMF method with a solid Ag<Subscript>4</Subscript>RbI<Subscript>5</Subscript> electrolyte

The EMF method with a solid Ag₄RbI₅ superionic conductor was used to study the Ag-As-Se and Ag-S-I systems in the composition ranges of Ag₂Se-As₂Se₃-Se and Ag₂S-AgI-S, accordingly. Their solid-phase equilibrium diagrams are constructed or specified. The existence of ternary AgAs₃Se₅, AgAsSe₂, Ag₃AsSe₃, Ag₇AsSe₆, Ag₃SI compounds is confirmed. The standard partial and integral thermodynamic formation functions and also standard entropies were calculated for these compounds for the first time.     

Thermodynamic study of glasses in Ag-As-Se system using EMF method with Ag<Subscript>4</Subscript>RbI<Subscript>5</Subscript> solid electrolyte

The EMF method with Ag₄RbI₅ solid electrolyte was used to study silver solubility in Ag-As-Se glasses on the basis of the cross-sections of (I) Ag-As_0.25Se_0.75, (II) Ag-As_0.33Se_0.67, (III) Ag-As_0.4Se_0.6, and (IV) Ag-As_0.5Se_0.5. It is found that silver solubility reaches 30 and 40 at % in sections (I), (IV) and (II), (III), accordingly. The data of EMF measurements were used as a basis for calculation of partial polar functions of Ag in glasses. The Gibbs-Duhem equations were integrated to calculate thermodynamic functions of silver dissolution in vitreous As _x Se_{1 − x} (x = 0.25; 0.33; 0.4; 0.5), from which the corresponding data for the latter were used to obtain the standard integral thermodynamic functions of the mixing of glasses. The obtained results were compared with the thermodynamic data for crystalline silver selenoarsenites.     

Synthesis of acrylates based on tetracyclododecene and its methyl derivative

The reaction of catalytic and thermal addition of acrylic acid to tetracyclo[4.4.1^2,5.1^7,10.0^1,6]dodec-3-en and its 8-methyl-substituted derivative was studied. The reaction is intended for the synthesis of corresponding acrylates, which are reactive monomers suitable for producing high-molecular compounds.     

Synthesis of diesters by addition of acids to 5-alkoxycarbonylnorborn-2-ene and related 5-methyl derivatives

The addition of saturated aliphatic acids C₁?CC₅ to 5-alkoxycarbonylnorborn-2-enes and 5-methyl-5-alkoxycarbonylnorborn-2-enes in the presence of catalyst BF₃·O(C₂H₅)₂ was studied and new representatives of the norbornane hydroxyacids diesters were synthesized.     

Kinetics and Mechanism of Oxidative Dehydrodisproportionation of Methylcyclohexane on Modified High-Silica Zeolite H-TsVM

The kinetics of oxidative dehydrodisproportionation of methylcyclohexane in the presence of H-TsVM zeolite (SiO₂ : Al₂O₃ = 30) modified with gallium and gadolinium oxides was studied. A kinetic model fairly adequately describing this process in a wide temperature range was proposed. The kinetic constants of some oxidation reactions were determined.     

Diels-Alder reaction of <Emphasis Type="Italic">para</Emphasis>-substituted allyl and 2-propynyl benzoates with hexabromo- and tetrabromo-5,5-dimethoxy- 1,3-cyclopentadienes

para-Substituted 2-propynyl benzoates are more reactive than the corresponding allyl esters in the Diels-Alder reactions with hexabromo- and tetrabromo-5,5-dimethoxy-1,3-cyclopentadienes. The cycloaddition is favored by the presence of both electron-donor and electron-acceptor substituents in the aromatic ring, in keeping with the neutral reaction scheme. The reactivity of the addends is likely to be determined not only by their donor-acceptor properties but also by the localization energy.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 9, 2004, pp. 1324–1328.Original Russian Text Copyright © 2004 by Magerramov, Mustafaev, Velieva, Murshudova, Allakhverdiev.     

Thermodynamic functions of arsenic selenides

The solid-phase equilibria and thermodynamic properties of an As–Se system are studied using the electromotive force (EMF). The existence of compounds As₂Se₃, AsSe, and As₄Se₃ in a system with near constant composition is confirmed. The relative partial molar functions, standard Gibbs free energies, enthalpies of formation, and standard entropies of As in the alloys are calculated using EMF measurements.     

Fundamental kinetic aspects and the mechanism of oxidative dehydrogenation of 4-vinylcyclohexene into ethylbenzene and styrene on metal-containing zeolites of the pentasil family

In promotion of a Pt-Ga-containing pentasil with a binary mixture of REE oxides, a synergism of their effect on the catalyst activity in the reaction of oxidative dehydrogenation of 4-vinylcyclohexene is observed. A kinetic model of the process of oxidative dehydrogenation of 4-vinylcyclohexene is suggested. The model includes a stage-by-stage scheme and the corresponding reaction rate equations. It was found that the accumulation rate of 4-vinylcyclohexene dehydrogenation products is correlated with the isomerization capacity of the catalytic system.