Decomposition Of Tert-butyl Hydroperoxide Research Articles

Tert-butyl hydroperoxide decomposition as a descriptor for liquid-phase hydrocarbon oxidation over transition metal oxide-based catalysts: a screening study

Tert-butyl hydroperoxide decomposition as a descriptor for liquid-phase hydrocarbon oxidation over transition metal oxide-based catalysts: a screening study

Features of catalytic activity of binary systems based on d-metal compounds and cetyltrimethylammonium bromide for tert-butyl hydroperoxide decomposition as an example

Features of catalytic activity of binary systems based on d-metal compounds and cetyltrimethylammonium bromide for tert-butyl hydroperoxide decomposition as an example

Influence of tungsten compounds on reaction of 1-octene epoxidation by tert-butyl hydroperoxide and hydroperoxide decomposition

Catalytic ability of tungsten compounds in the reaction of hydroperoxide epoxidation of 1- octene and tert-butyl hydroperoxide decomposition was investigated. It is shown that the nature of ligand has significant effect on the catalytic activity of tungsten compounds in these reactions. It is established that boride and silicide of tungsten are the best choice for epoxidation reaction, whereas tungsten carbide exhibits poor activity. Tungsten boride is also the most active in the hydroxide decomposition reaction.

Radical Propagation Facilitating Aerobic Oxidation of Substituted Aromatics Promoted by Tert‐Butyl Hydroperoxide

AbstractThe selective oxidation of aromatics to synthesize valued‐added products is of great significance for chemical industry. Molecule oxygen as oxidant is the priority for this process, however, low efficiency was usually obtained. In this work, a new strategy for aromatics oxidation using O2 and Tert‐butyl hydroperoxide (TBHP) as dual oxidants without catalyst was proposed. Typical radical process was observed when Toluene was used as the substrate. As high as 47.1 % conversion and 87.6 % selectivity of benzol acid were obtained, while a negligible or low activity were observed under O2 or TBHP oxidative systems. Detailed investigation shows that the distribution of products was almost the same between TBHP+N2 and TBHP+O2 processes, in which the very close active energies were obtained (46.0 and 46.3 kJ/mol). These results indicated that TBHP+N2 or TBHP+O2 involved reactions underwent the same reaction process. The mechanism study demonstrated that the decomposition of TBHP could produce abundance of t‐BuO. and .OH radicals, which significantly enhanced the αH abstraction from toluene and formed alkyl radicals. The alkyl radicals then react with O2 to produce peroxides, which started the radical propagation cycle. The overall rate would be enhanced subsequently. Furthermore, an extension application of other aromatic substrates was investigated and displayed a great promising future to produce aromatic products.

Ni(II) Chelates + Cetyltrimethylammonium Bromide] Composition: Characteristics of Catalytic Activity, Using the Reaction of tert-Butyl Hydroperoxide Decomposition As an Example

Ni(II) Chelates + Cetyltrimethylammonium Bromide] Composition: Characteristics of Catalytic Activity, Using the Reaction of tert-Butyl Hydroperoxide Decomposition As an Example

Photoinduced Enhanced Decomposition of TBHP: A Convenient and Greener Pathway for Aqueous Domino Synthesis of Quinazolinones and Quinoxalines

Catalyst-free photoinduced processes in aqueous medium represent significant advancement toward development of green and sustainable pathways in organic synthesis. tert-Butyl hydroperoxide (TBHP) is a widely used oxidant in organic reactions, where the decomposition of TBHP into its radicals by metal catalysts or other reagents is a key factor for efficient catalytic outcome. Herein, we report a simple and environmentally friendly visible light-promoted synthetic pathway for the synthesis of N-heterocyclic moieties, such as quinazolinones and quinoxalines, in the presence of TBHP as an oxidizing agent in aqueous medium that requires no catalysts/photocatalysts. The enhanced rate of decomposition to generate free radicals from TBHP upon visible light irradiation is the driving force for the domino reaction.

Aсtivity of binary vinadium compounds in reaction of epoxidation of 1-octene and decomposition of tert-butyl hydroperoxide

The influenceof vanadium-containing compounds as catalysts on the reaction of 1-octene epoxidation by tert-butyl hydroperoxide and the decomposition of this hydroperoxide was investigated. It is shown that the catalytic activity of vanadium compounds depends on catalyst ligand nature. It is established that vanadium boride and carbide are the most active catalysts for

Towards Mechanistic Understanding of Liquid-Phase Cinnamyl Alcohol Oxidation with tert-Butyl Hydroperoxide over Noble-Metal-Free LaCo1-x Fex O3 Perovskites.

Noble-metal-free perovskite oxides are promising and well-known catalysts for high-temperature gas-phase oxidation reactions, but their application in selective oxidation reactions in the liquid phase has rarely been studied. We report the liquid-phase oxidation of cinnamyl alcohol over spray-flame synthesized LaCo1-x Fex O3 perovskite nanoparticles with tert-butyl hydroperoxide (TBHP) as the oxidizing agent under mild reaction conditions. The catalysts were characterized by XRD, BET, EDS and elemental analysis. LaCo0.8 Fe0.2 O3 showed the best catalytic properties indicating a synergistic effect between cobalt and iron. The catalysts were found to be stable against metal leaching as proven by hot filtration, and the observed slight deactivation is presumably due to segregation as determined by EDS. Kinetic studies revealed an apparent activation energy of 63.6 kJ mol-1 . Combining kinetic findings with TBHP decomposition as well as control experiments revealed a complex reaction network.

Initiator Based on the Cu(II) and Cetyl Trimethyl Ammonium Bromide Compounds that Generates Free Radicals in the Decomposition of tert-Butyl Hydroperoxide in Optimum Temperature Conditions

The two-component composition consisting of complex copper Cu(II) compounds and cationic surface-activated substance cetyl trimethyl ammonium bromide (CTAB) exhibits high catalytic reactivity during decomposition of tert-butyl hydroperoxide. One specific characteristic of the effects of the Cu(II) + CTAB binary system consists in its high rate of processing without visible signs of deactivation in the transformation of significant amounts of the reagent in optimum temperature conditions.

On the thermal decomposition of tert.-butyl hydroperoxide, its sensitivity to metals and its kinetics, studied by thermoanalytic methods

The decomposition of hydroperoxides like tert.-butyl hydroperoxide (TBHP) due to reactions with reactor materials (wall reactions) is an important issue in the frame of industrial processes and the analysis of such compounds. Because of the high surface-volume ratio such heterogeneous reactions are also especially important in case of thermo-analytical measurements. Therefore, the decomposition of TBHP has been studied for the first time extensively by Differential Scanning Calorimetry (DSC) using differently coated high pressure stainless steel crucibles (uncoated, gilded, silicon coated) and a medium pressure stainless steel crucible. Furthermore, the interaction of such crucible materials with TBHP has been measured for the first time by Thermal Activity Monitoring (TAM). The material of the gilded copper blowout disc turned out to be the reason for the very different DSC curves published in literature and had the highest influence compared to the crucible body material and the pressure. To protect the sample against the blowout disc, an aluminium foil has been placed below the blowout disc. This changed the shape of the DSC curve completely. It became more similar to that obtained with the medium pressure crucible. Furthermore, the reaction mechanism, kinetics and chemical aspects of the decomposition of TBHP at different conditions have been discussed and kinetics has been investigated for the first time by an overall evaluation of the DSC curves and a model free kinetics approach. Using the linear relationship between the kinetic activation parameters the published values are compared to those of the present work.

One-Pot Magnetic Iron Oxide-Carbon Nanodot Composite-Catalyzed Cyclooxidative Aqueous Tandem Synthesis of Quinazolinones in the Presence of tert-Butyl Hydroperoxide.

The development of synthetic protocols for biologically important molecules using biocompatible catalysts in aqueous medium holds the key in green and sustainable chemistry. Herein, a magnetically recoverable iron oxide–carbon dot nanocomposite has been demonstrated as an effective catalyst for cyclooxidative tandem synthesis of quinazolinones in aqueous medium using alcohols as starting materials. Fluorescent carbon dots, the newest entrant in the nanocarbon family, were used as the stabilizing agent for the iron oxide nanoparticles, and a continuous layer of carbon dots decorates the iron oxide nanoparticle surface as observed by transmission electron microscopy. The fluorescence studies demonstrated the effective electron transfer from carbon dots to the iron oxide nanoparticles resulting in complete quenching of emission owing to carbon dots, once it binds with iron oxide nanoparticles. The nanocatalyst showed high activity with significant reusability for the syntheses of quinazolinones in the presence of tert-butyl hydroperoxide (TBHP) in an aqueous medium. Controlled experiments revealed the synergistic effect of carbon dots in enhancing the catalytic activity of iron oxide, as they might influence the decomposition of TBHP into radicals owing to their peroxidase activity. These radicals stabilized over the nanoparticle surface are known to have increased lifetime compared to solution-based radicals. These surface-stabilized radicals then could catalyze the tandem reaction resulting in the formation of the quinazolinone derivatives in high yields.

Decomposition of tert-Butyl Hydroperoxide in the Presence of Selected Initiators and Catalysts

Decomposition of tert-Butyl Hydroperoxide in the Presence of Selected Initiators and Catalysts

Thermodynamic Analysis of α‐Pinene and Limonene Allylic Oxidation over a FePcCl16‐NH2‐SiO2 Catalyst

AbstractFrom oxidation over a FePcCl16‐NH2‐SiO2 catalyst and tert‐butyl hydroperoxide (TBHP) as oxidant, verbenone, α‐pinene epoxide, and verbenol were obtained from α‐pinene while carvone, limonene 1,2‐epoxide and carveol were produced from limonene. TBHP decomposes into O2, tert‐butanol, and di‐tert‐butyl peroxide (DTBP). With the aim to perform a batch‐reactor conceptual design, α‐pinene and limonene oxidation was thermodynamically analyzed. Standard enthalpy and entropy of formation, liquid heat capacity, enthalpy of reaction and vaporization, and Gibbs free energy were determined by group contribution methods using Aspen Plus® simulation. Although the results depend on the method, it was found that α‐pinene and limonene oxidations were exothermic and spontaneous at the selected reaction temperature. However, TBHP decomposition into O2, tert‐butanol, and DTBP was an endothermic reaction.

Iron Nanoparticles Embedded in Graphitic Carbon Matrix as Heterogeneous Catalysts for the Oxidative C−N Coupling of Aromatic N−H Compounds and Amides

AbstractFe or Co nanoparticles (NPs) and two nanoparticulate Fe‐Co alloys having different Fe/Co atomic ratio with average particle size ranging from 10.9 to 26.5 nm embedded in turbostratic graphitic carbon matrix have been prepared by pyrolysis at 900 °C under inert atmosphere of chitosan powders containing Fe2+ and Co2+ ions in various proportions. The resulting Fe/Co NP@C samples have been evaluated as heterogeneous catalysts for the oxidative C−N coupling of amides and aromatic N−H compounds. It was observed that sequential addition of two aliquots of tert‐butyl hydroperoxide (TBHP) in an excess of N,N‐dimethylacetamide (DMA) as solvent affords the corresponding coupling product in high yields, and the most efficient catalyst was Fe NP@C. Fe NP@C is reusable and exhibits a wide scope. The catalytic activity of Fe is supported by using highly pure Fe salt and by the observation that purposely addition of Cu2+ impurities even plays a detrimental effect on the catalytic activity. Mechanistic studies by quenching with 2,2,6,6‐tetramethylpiperidyl‐1‐oxyl (TEMPO) have shown that the amide radical is the key reaction intermediate, and the role of Fe NP@C is to generate the first radicals by TBHP decomposition.

Characterization on thermal decompositions of tert-butyl hydroperoxide (TBHP) by confinement test

Thermal decomposition of 20 mass% aqueous tert-butyl hydroperoxide (TBHP) is performed by confined apparatus as a model reaction. Inductive effects are verified by of hydroxyl and tert-butoxy radicals produced by the thermolysis of H2O2 and di-tert-butyl peroxide (DTBP), respectively. Solvent effects are performed by 20 mass% TBHP in acetone, n-butyl alcohol, decane, nonane, Nujol, toluene and H2O. Thermodynamic and kinetic features, such as exothermic onset temperature, adiabatic temperature rise, maximum self-heat rate, maximum pressure and maximum temperature, are thus measured and utilized to characterize these mentioned influences. Hydroxyl radical is firstly discovered to possess the highest inductive effect on decomposition of TBHP. Exothermic onset temperature of 20 mass% aqueous TBHP is lowered from 146.0 ± 1.0 to 138.0 ± 2.0, 133.0 ± 0.0, 97 ± 8.8 and 89 °C by adding 10 mass% DTBP, 20 mass% DTBP, 10 mass% H2O2 and 20 mass% H2O2 relative to the mass of TBHP, respectively. The ranking of solvent effects on the thermal stability of solvated TBHP identified by exothermic onset temperature is arranged from high to low in the following: TBHP in toluene (178.5 ± 1.5 °C) > TBHP in decane (151.0 ± 2.0 °C) > TBHP in H2O (146.0 ± 1.0 °C) > TBHP in nonane (143.5 ± 2.5 °C) > TBHP in Nujol (138.5 ± 0.5 °C) > TBHP in acetone (128.0 ± 2.0 °C) > TBHP in n-BuOH (122.5 ± 3.5 °C).

Nontransition metal–crown ether complexes as hydroperoxide decomposition catalysts

The decomposition of tert-butyl hydroperoxide in a chlorobenzene medium in the presence of complexes of dibenzo-18-crown-6 with calcium, strontium, and barium chlorides has been studied. It has been found and kinetically proven that the decomposition of tert-butyl hydroperoxide is preceded by the formation of an intermediate hydroperoxide–catalyst complex. Kinetic and thermodynamic parameters of the complex formation have been determined.

A Shock-Tube Study of the CO + OH Reaction Near the Low-Pressure Limit.

Rate coefficients for the reaction between carbon monoxide and hydroxyl radical were measured behind reflected shock waves over 700-1230 K and 1.2-9.8 bar. The temperature/pressure conditions correspond to the predicted low-pressure limit of this reaction, where the channel leading to carbon dioxide formation is dominant. The reaction rate coefficients were inferred by measuring the formation of carbon dioxide using quantum cascade laser absorption near 4.2 μm. Experiments were performed under pseudo-first-order conditions with tert-butyl hydroperoxide (TBHP) as the OH precursor. Using ultraviolet laser absorption by OH radicals, the TBHP decomposition rate was measured to quantify potential facility effects under extremely dilute conditions used here. The measured CO + OH rate coefficients are provided in Arrhenius form for three different pressure ranges: kCO+OH(1.2-1.6 bar) = (9.14 ± 2.17) × 10(-13) exp(-(1265 ± 190)/T) cm(3) molecule(-1) s(-1); kCO+OH(4.3-5.1 bar) = (8.70 ± 0.84) × 10(-13) exp(-(1156 ± 83)/T) cm(3) molecule(-1) s(-1); and kCO+OH(9.6-9.8 bar) = (7.48 ± 1.92) × 10(-13) exp(-(929 ± 192)/T) cm(3) molecule(-1) s(-1). The measured rate coefficients are found to be lower than the master equation modeling results by Weston et al. [J. Phys. Chem. A, 2013, 117, 821] at 819 K and in closer agreement with the expression provided by Joshi and Wang [Int. J. Chem. Kinet., 2006, 38, 57].

Dibenzo-18-crown-6 as a catalyst for tert-butyl hydroperoxide decomposition

Degradation of tert-butyl hydroperoxide in chlorobenzene in the presence of dibenzo-18-crown-6 ether has been studied. It has been established and kinetically proven that the degradation is preceded by the formation of an intermediate complex of the hydroperoxide with the crown ether. The composition of the complex and thermodynamic and kinetic parameters of its formation and decomposition have been determined.

Chemical Kinetics of Disproportionation Decomposition of tert-Butyl Hydroperoxide Catalyzed by Buserite-type Manganese Oxides

Chemical Kinetics of Disproportionation Decomposition of tert-Butyl Hydroperoxide Catalyzed by Buserite-type Manganese Oxides

A shock tube study of CH3OH + OH → Products using OH laser absorption

The rate coefficient for the reaction of methanol (CH3OH) with the hydroxyl (OH) radical was determined in reflected shock wave experiments at temperatures of 961–1231K and pressures of 1.18–1.48atm. Pseudo-first order reaction conditions were achieved with mixtures of CH3OH and tert-butyl hydroperoxide (TBHP) diluted in argon. Rapid thermal decomposition of TBHP at high temperatures was used as a fast OH radical source, and OH time-histories were measured using laser absorption of OH radicals near 306.7nm. The rate coefficient of the title reaction was found from best-fit comparison of simulated OH profiles with measured data, using simulations from the Wang et al. USC-Mech II reaction mechanism (2007). A detailed uncertainty analysis was performed, with estimated uncertainties of −10%/+17% at 961K and −12%/+18% at 1231K. The current results agree well with the results of Vandooren and Van Tiggelen (1981), Hess and Tully (1989), and Xu and Lin (2007). The three-parameter Arrhenius expression k1(210–1231K)=5.71×104T2.62exp(343/T[K]) cm3mol−1s−1 is recommended from a fit to the combined data of Hess and Tully (1989), Jiménez et al. (2003), Dillon et al. (2005), and the current work.