Emulsion polymerization of vinyl chloride, 2 potassium persulfats decomposition in the presence of PVC latex

The decomposition rate of potassium persulfate (KPS) in aqueous solutions, in the presence of sodium dodecyl sulfate (SDS) and poly(vinyl chloride) latex (PVC) was studied. The dissolved SDS increases the decomposition rate constant (k_d) while the SDS aggregation as micella and/or its adsorption on the polymer hydrophobic surface results in a decreasing k_d. The emulsifier - free surface of the polymer particles increases the decomposition rate. A reaction mechanism based on emulsifier - emulsifier and emulsifier - polymer hydrophobic interactions is put forward.     

Reactions of arenediazonium tetrafluoroborates with 3-chloro-2-methylpropene in the presence of potassium chloride,bromide, and thiocyanate

Arenediazonium tetrafluoroborates reacted with 3-chloro-2-methylpropene in the presence of potassium chloride, bromide, and thiocyanate to give the corresponding 1-aryl-3-chloro-2-halo(thiocyanato)-2-methylpropanes. The presence of a copper salt is a necessary condition for the reaction to occur. The yields of the corresponding 1-aryl-3-chloro-2-halo-2-methylpropanes in the Meerwein reaction were approximately twice as low. Introduction of a methyl group to C2 in the 3-chloropropene molecule does not change the reaction regioselectivity.     

Reaction of potassium dialkyl thiophosphates with ethynyl bromides in the presence of cupric chloride

Conclusions The reaction of potassium diethyl thiophosphate with phenylbromoacetylene in the presence of equivalent amounts of cupric chloride gives 0,0-diethyl S-phenylethynyl thiophosphate. The cuprous salt of diethylthiophosphate acid is formed as an intermediate which reacts with the ethynyl bromide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 467–469, February, 1986.     

A study of the oxyanion effect in reactions of 2-methyl-2-propen-1-ol

Optimum conditions for the self reaction of the potassium alkoxide of 2-methyl-2-propen-1-ol to give 3,5,5,-trimethyltetrahydropyran-2-ol (7) have been developed. Evidence is presented to demonstrate that the key carbon carbon bond forming step in this reaction formally involves an unusual type of Ene reaction between 2-methylpropenal and the allylic alkoxide anion in which stepwise or highly asynchronous hydride transfer precedes carbon carbon bond formation. Under different reactions conditions the condensation of 2-methylpropenal with the potassium alkoxide of 2-methyl-2-propen-1-ol proceeds to give the bicyclic lactone, 6-endo-hydroxy-7-exo-(2-methyl allyioxymethyl)-3-oxa-1,5,7-trimethyl bicyclo[3,3,1]nonan-2-one (11), the crystal structure of which is reported.     

Hydration of sodium, potassium, and chloride ions in solution and the concept of structure maker/breaker

Neutron diffraction data with hydrogen isotope substitution on aqueous solutions of NaCl and KCl at concentrations ranging from high dilution to near-saturation are analyzed using the Empirical Potential Structure Refinement technique. Information on both the ion hydration shells and the microscopic structure of the solvent is extracted. Apart from obvious effects due to the different radii of the three ions investigated, it is found that water molecules in the hydration shell of K+ are orientationally more disordered than those hydrating a Na+ ion and are inclined to orient their dipole moments tangentially to the hydration sphere. Cl- ions form instead hydrogen-bonded bridges with water molecules and are readily accommodated into the H-bond network of water. The results are used to show that concepts such as structure maker/breaker, largely based on thermodynamic data, are not helpful in understanding how these ions interact with water at the molecular level.     

NMR spectroscopic study of the (Z)/(E)-isomerism of 1-aryl-3-arylamino-2-propen-1-ones in solution and in the crystalline state

Summary ¹H,¹³C, and CP/MAS¹³C NMR spectra of sixp-substituted 1-aryl-3-arylamino-2-propen-1-ones in solution and in the solid state are reported and discussed. In the proteon-accepting solvent dimethylsulfoxide, electronegative substituents shift the isomeric equilibrium to the (E)-isomer. Bulky substituents promote crystallization of the (Z)-form.

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NMR-Spektroskopische Untersuchung der (Z)/(E)-Isomerie von 1-Aryl-3-arylamino-2-propen-1-onen in Lösung und im Kristallzustand (Kurze Mitt.)

Zusammenfassung ¹H-,¹³C- und CP/MAS-¹³C-NMR Spektren von sechsp-substituierten 1-Aryl-3-arylamino-2-propen-1-onen in gelöstem und festem Zustand werden berichtet und diskutiert. In protonenakzeptierendem Dimethylsulfoxid verschieben elektronegative Substituenten das Gleichgewicht zum (E)-Isomer. Große Substituenten begünstigen die Kristallisation in der (Z)-Form.

     

Peculiarities in the photochemical behavior of 1-bromo-2-hydroxynaphthalene in cetylpyridinium chloride micellar solution

Unlike the case of aqueous solution, two products are formed in the photolysis of 1-bromo-2-hydroxynaphthalene in a cetylpyridinium chloride micellar solution in the presence of sodium sulfite. These products are formed as a result of competitive steps of the primary photochemical process, the C–Br bond photodissociation and the heterolytic dissociation with elimination of the bromide anion. The bond photodissociation results in the product of bromine replacement by the sulfo group. The heterolytic dissociation affords the dimerization product. In the micellar solution, the iodide ions increase the quantum yield of the photosubstitution product due to the heavy atom effect and do not affect the quantum yield of the dimerization product. The halogenated derivatives of hydroxynaphthalene in micelles do not fluoresce in a neutral or alkaline medium.     

Hyperfine interactions in the microwave spectrum of 2-propen-1-Imine (vinylimine)

A high resolution study of the microwave spectrum of 2-propen-1-imine has yielded values for ¹⁴N hyperfine coupling constants for both the trans-syn and trans-anti isomers. In the latter case, evidence was found for magnetic spin-rotation interaction. Rotational and centrifugal distortion constants of improved accuracy have been derived in the course of the analysis.     

氯化钠存在下丙醇-碘化钾体系萃取分离铂、钯的研究

研究了氯化钠存在下丙醇－碘化钾体系对铂（Ⅱ）、钯（Ⅱ）萃取行为及体系在盐酸介质中的分相条件。在盐酸介质中,体系可同时萃取铂（Ⅱ）、钯（Ⅱ）,萃取率分别为99．8％、99．4％,方法可用于从贱金属中分离铂、铯 。对阳极泥、砂铂矿、废催化剂样品中的铂、钯进行了分离,分析结果与其它方法相符,并对萃取机理也进行了探讨。     

Ph~2C(OH)CH=CHSnAr~3的卤化物的合成、表征和性质

首次以非碳环醇(Z)-3-三芳基锡基-1,1-二苯基-2-丙烯基-1-醇[Ph~2C(OH)CH=CHSnAr~3]和卤素或拟卤素发生取代反应得到卤化物,并以此合成了氢氧化物、氧化物和配合物。通过元素分析、IR和^1HNMR等对上述17种新化合物的结构进行了表征,并提出了卤化物的性质。     

Bromination of 2-benzoylthiophene in the presence of excess aluminum chloride

Russian Chemical Bulletin -     

The addition of hydrogen chloride to alk-1-enes in the presence of dicyclohexyl peroxydicarbonate,iron pentacarbonyl,and ferric chloride

Russian Chemical Bulletin -     

Formation of hexenes from 1-pentanol in the presence of cupric chloride

Conclusions The dehydration of 1-pentanol in the presence of CuCl₂ at 140–200 and a pressure of 5–80 atm, in either a CO or a N₂ atmosphere, is accompanied by the formation, along with pentenes, of large amounts of hexenes (mainly cis- and trans-2-hexene).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1886–1887, August, 1973.     

Catalytic acylation of benzoxazolin-2-ones in the presence of zinc chloride

In the acylation of benzoxazolin-2-ones by aromatic acid chlorides in the presence of 10^-2 mole of ZnCl₂, the yields of the corresponding 6-aroylbenzoxazolin-2-ones depend on the electronegativity of the acylating agent and the nucleophilicity of the benzoxazolin-2-ones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1136–1138, August, 1994.     

Microwave-assisted solvent-free synthesis of 2-styrylquinolines in the presence of zinc chloride

An efficient solvent-free procedure has been developed for the synthesis of (E)-2-styrylquinoline derivatives under microwave irradiation in the presence of zinc chloride. The developed procedure is advantageous due to shorter reaction time and simpler workup.     

Placement of cations in NaX faujasite-type zeolite using (N,V,T) Monte Carlo simulations

The cation distribution in dehydrated NaX was predicted using appropriate interatomic potentials and (N,V,T) simulations, considering the cations as 'guest' particles and the framework as a 'host'; the simulations not only yield the expected different types of sites, but also highlight the cooperative placement of supercage cations which results essentially from electrostatic interactions between the cations.