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Thermal decomposittion of the acetone cyclic diperoxide in 1-octanol solution
Leiva,Laura C. A; Jorge,Nelly L; Romero,Jorge M; Cafferata,Lázaro F. R; Gómez Vara,Manuel E; Castro,Eduardo A;
The Journal of Argentine Chemical Society , 2008,
Abstract: the thermal decomposition reaction of acetone cyclic diperoxide (acdp) in 1-octanol (oct) solution, at the temperatures and initial concentration ranges of 130° - 166 oc and (0.94-3.00) x 10-2 mol/l , respectively, follows a pseudo-first order kinetic law. acetone is the main organic decomposition product observed. the activation parameters values of the initial reaction step (dh# = 25.8 ± 0.3 kcal/mol; ds# = -19.1 ± 0.6 cal/mol k; ea = 26.6 ± 0.3 kcal/mol), support a reaction mechanism which includes a homolytic rupture of one peroxidic bond of the acdp molecule with participation of the solvent and involving a biradical intermediate.
Efecto de solvente sobre la descomposición térmica de trans-3,6-dimetil-3,6-difenil-1,2,4,5-tetraoxaciclohexano en solución
Eyler, Gladys N.;Ca?izo, Adriana I.;Mateo, Carmen M.;
Química Nova , 2004, DOI: 10.1590/S0100-40422004000600016
Abstract: the thermal decomposition reaction of trans-3,6-dimethyl-3,6-diphenyl-1,2,4,5-tetraoxacyclohexane (acetophenone cyclic diperoxide, dpaf), in different solvents (methanol, 1,4-dioxane, acetonitrile and 2-propanol/benzene mixtures) in the initial concentration and temperature ranges of (4.2-10.5) x 10-3 m and 140.0 to 185.0 oc, respectively, follows a pseudo first order kinetic law up to at least 70% dpaf conversion. an important solvent effect on the rate constant values, activation parameters (dh# and ds#) and reaction products obtained in different solvents is detected, showing that the reaction is accelerated in alcohols.
Efecto de solvente sobre la descomposición térmica de trans-3,6-dimetil-3,6-difenil-1,2,4,5-tetraoxaciclohexano en solución  [cached]
Eyler Gladys N.,Ca?izo Adriana I.,Mateo Carmen M.
Química Nova , 2004,
Abstract: The thermal decomposition reaction of trans-3,6-dimethyl-3,6-diphenyl-1,2,4,5-tetraoxacyclohexane (acetophenone cyclic diperoxide, DPAF), in different solvents (methanol, 1,4-dioxane, acetonitrile and 2-propanol/benzene mixtures) in the initial concentration and temperature ranges of (4.2-10.5) x 10-3 M and 140.0 to 185.0 oC, respectively, follows a pseudo first order kinetic law up to at least 70% DPAF conversion. An important solvent effect on the rate constant values, activation parameters (DH# and DS#) and reaction products obtained in different solvents is detected, showing that the reaction is accelerated in alcohols.
Thermophysical Properties of Binary Liquid Systems of Ethanoic Acid, Propanoic Acid, and Butanoic Acid with Benzene or Acetophenone  [PDF]
R. Ahluwalia,Ritu Gupta,J. L. Vashisht,R. K. Wanchoo
ISRN Physical Chemistry , 2013, DOI: 10.1155/2013/612837
Abstract: The density ( ), viscosity ( ), and surface tension ( ) of binary mixtures of carboxylic acids (CAs) (ethanoic acid (EA), propanoic acid (PA), butanoic acid (BA)) + benzene (BEN) or acetophenone (ACT) have been measured at 298.15, 308.15, and 318.15?K. From the experimental results, excess values of molar volume ( ), viscosity ( ), Gibb's free energy for the activation of low ( ), and surface tension ( ) were evaluated and fitted to a Redlich-Kister type of equation. The parameter “ ” of Grunberg and Nissan expression has also been calculated. From the sign and magnitude of , , , , and “ ” values, it is concluded that specific interactions are present in CA+ACT system and these interactions are absent in CA + BEN mixtures. Various viscosity and surface tension models have been used to test the consistency of the data. 1. Introduction Studies on thermophysical properties of binary liquid mixtures containing carboxylic acids are not extensive [1–3]. In view of this, we have undertaken studies on binary mixtures of carboxylic acids (CAs), namely, ethanoic acid (EA), propanoic acid (PA), and butanoic acid (BA) which are self-associated solvents, with a nonpolar solvent benzene (BEN) and polar acetophenone (ACT). These acids exist as cyclic dimers in the pure state. However, trimers also exist which are formed because of strong interactions between ring dimers and monomers [4–6]. The excess properties , , , , and Grunberg and Nissan parameter “ ” computed from the experimental data (density ( ), viscosity ( ), and surface tension) ( )) of binary mixtures of carboxylic acids (EA, PA, BA) with benzene and acetophenone have been determined. Benzene interacts with acid through Vander Waal's or London dispersion forces and acetophenone forms chemical aggregates with acid through hydrogen bonding. The results are used to theoretically justify the validity of various viscosity and surface tension models. The main thrust of the investigation is to correlate the experimental data in terms of the interacting components of the mixtures and to stress the factors affecting these interactions. 2. Experimental Section Ethanoic acid, propanoic acid, butanoic acid, benzene, and acetophenone were purified by the standard methods described in the literature [7]. Ethanoic acid (BDH, 99% assay) was washed with a calculated amount of acetic anhydride for about 10?h and was subjected to fractional distillation. Propanoic acid and butanoic acid (E. Merck, 99% assay) were dried over anhydrous sodium sulfate for two days and the samples were distilled over potassium permanganate.
Dynamic Interactions of CdSe/ZnS Quantum Dots with Cyclic Solvents Probed by Femtosecond Four-Wave Mixing  [cached]
Hirosawa Y.,Kouzai H.,Miyagawa H.,Tsurumachi N.
EPJ Web of Conferences , 2013, DOI: 10.1051/epjconf/20134104036
Abstract: We studied dynamic interactions between CdSe/ZnS quantum dots (QDs) and cyclic solvents probed by femtosecond four-wave mixing. We found that the dynamic interactions of QDs strongly depend on the existence of π-bonds in solvent molecules.
Proline-Catalysed Amination Reactions in Cyclic Carbonate Solvents  [PDF]
Christopher Beattie,Michael North,Pedro Villuendas
Molecules , 2011, DOI: 10.3390/molecules16043420
Abstract: Propylene carbonate is shown to be an environmentally friendly and sustainable replacement for dichloromethane and acetonitrile in proline-catalysed a-hydrazinations of aldehydes and ketones. Enantioselectivities comparable to those obtained in conventional solvents or ionic liquids can be obtained, even when using a lower catalyst loading.
Calorimetric and Computational Study of Enthalpy of Formation of Diperoxide of Cyclohexanone  [PDF]
Jorge Marcelo Romero,Soledad Bustillo,Hugo Enrique Ramirez Maisuls,Nelly Lidia Jorge,Manuel Eduardo Gómez Vara,Eduardo Alberto Castro,Alicia H. Jubert
International Journal of Molecular Sciences , 2007, DOI: 10.3390/i8070688
Abstract: A thermochemical rather simple experimental technique is applied to determinethe enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented withsuitable theoretical calculations at the semiempirical and ab initio levels. A particularsatisfactory agreement between both ways is found for the ab initio calculation at the 6-311G basis This set level. Some possible extensions of the present procedure are pointedout.
Asymmetric Reduction of 3,5-Bistrifluoromethyl Acetophenone with NADH Regeneration by Immobilized Cells of Saccharomyces rhodotorula in Aqueous-Organic Solvent Biphasic System
ZHANGFang,XUEYing,LILi,WANG Min,
张芳
,薛颖,李莉,王旻

过程工程学报 , 2011,
Abstract: Asymmetric reduction of 3,5-bistrifluoromethyl acetophenone to produce(S)-3,5-bistrifluoromethylphenyl ethanol was successfully carried out with sodium alginate immobilized Saccharomyces rhodotorula cells in an aqueous-organic solvent biphasic system.The possible influential factors were examined thoroughly according to their effects on conversion rate and e.e of the product.Organic solvents were rated by their biocompatibility and conversion potential.The immobilized cells 125 mg/mL in 20 mmol/L Tris-HCl ...
Synthesis and properties of aromatic 1,3-diketones and bis-(1,3-diketones) obtained from acetophenone and phtalic acids esters  [cached]
Jan Zawadiak,Marek Mrzyczek,Tomasz Piotrowski
European Journal of Chemistry , 2011, DOI: 10.5155/eurjchem.2.3.289-294.416
Abstract: Dibenzoylmethane and six aromatic 1,3-diketones containing a dibenzoylmethane moiety were synthesized from acetophenone and the appropriate ester in crossed-Claisen condensations. The synthesized diketones include derivatives containing carboxyl and ester groups; bis-(1,3-diketones) were also prepared. The absorption of UV radiation of the obtained compounds was investigated in various solvents, and their molar absorption coefficients were calculated. The ratio of tautomers and keto-enol equilibrium constants were calculated using 1H NMR techniques. Aromatic bis-(1,3-diketones) demonstrated strong hyperchromic effects. The keto-enol equilibrium of the investigated compounds is strongly shifted to the enol form, especially in non-polar solvents.
Experimental Study of the Thermophysical and Acoustical Properties of Acetophenone and Propylacetate
Science and Technology , 2012, DOI: 10.5923/j.scit.20120203.04
Abstract: Densities, viscosities, refractive indices and ultrasonic velocities of the binary mixtures of Acetophenone with Propyl acetate were measured over the entire mole fractions at (303.15, 313.15 and 323.15) K. From these experimental results, excess molar volumes VE, viscosity deviation η, refractive index deviation nD, deviations in isentropic compressibility Ks and excess intermolecular free length Lf are calculated. The viscosity values were fitted to the models of Krishnan- Laddha and McAllister. The thermo physical properties under study were fit to the Jouyban - Acree model. The excess values were correlated using Redlich-Kister polynomial equation to obtain their coefficients and standard deviations. It was found that in all cases, the data obtained fitted with the values correlated by the corresponding models very well. The results are interpreted in terms of molecular interactions occurring in the solution.
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