513-86-0Relevant articles and documents
Vapor-phase catalytic dehydration of 2,3-butanediol to 3-buten-2-ol over ZrO2 modified with alkaline earth metal oxides
Duan, Hailing,Yamada, Yasuhiro,Kubo, Shingo,Sato, Satoshi
, p. 66 - 74 (2017)
Vapor-phase catalytic dehydration of 2,3-butanediol (2,3-BDO) to produce 3-buten-2-ol (3B2OL) was investigated over several monoclinic ZrO2 (m-ZrO2) catalysts modified with alkaline earth metal oxides (MOs), such as SrO, BaO, and MgO, to compare with the previously reported CaO/m-ZrO2. It was found that these modifiers enhanced the 3B2OL formation to the same level as CaO did by loading an appropriate MO content. Among all the tested catalysts, the BaO/m-ZrO2 calcined at 800?°C with a low BaO content (molar ratio of BaO/ZrO2?=?0.0452) shows the highest 2,3-BDO conversion (72.4%) and 3B2OL selectivity (74.4%) in the initial stage of 5?h at 350?°C. In order to characterize those catalysts, their catalytic activities, crystal structures, and basic properties were studied in detail. In X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) experiment, it was elucidated that highly dispersed M-O-Zr (M?=?Ca, Sr, and Ba) hetero-linkages were formed on the surface by loading these MOs onto m-ZrO2 with an appropriate content and then calcining at 800?°C. It can be concluded that the M-O-Zr hetero-linkages generate the proper base-acid balance for the efficient formation of 3B2OL from 2,3-BDO.
Kinetics and Mechanisms of Oxidations by Metal Ions. V. Oxidation of 4-Oxopentanoic Acid by the Aquavanadium(V) Ion
Mehrotra, Raj Narain
, p. 2389 - 2394 (1985)
The outer sphere oxidation of 4-oxopentanoic acid (4-OPA), studied at 50 deg C by aquavanadium (V) ion, is H(1+)-catalyzed reaction.The reaction has a first-order dependence on each of , , and .The H(1+) catalysis can not be ascribed to keto enol equilibrium because of the knowledge that a γ-keto acid is the least enolized amongst keto acids.Hence V(OH)3(2+)(aq) ion is the active oxidant.The proposed mechanism, assumed to involve the initial decarboxylation, is supported by the spot test characterization of acetoin as the intermediate oxidation product.Acetoin is further oxidized to two moles of acetic acid which is the final oxidation product.The overall energy of activation (ΔH1=26+/-3 kJ mol-1) is lower than the normal value (84 kJ mol-1) and therefore the highly negative value of the overall entropy of activation (ΔS1=-268+/-8 JK-1 mol-1) is considered to be responsible for the observed slowrate of oxidation.
Influence of Br- Concentration on (Br)+-Mediated Indirect Electrooxidation of Alcohols to the Corresponding Carbonyl Compounds
Takiguchi, Tsuyoshi,Nonaka, Tsutomu
, p. 3137 - 3142 (1987)
Current efficiency for the (Br)+ (positive bromine species)-mediated indirect electrooxidation of alcohols to the corresponding carbonyl compounds decreased with increase in Br- concentration in dichloromethane and aqueous acidic solutions, while no concentration dependence was observed in an aqueous neutral solution.These facts suggested a general practical guideline for the indirect electrooxidation, i.e. low Br- concentration is favorable in an electrolytic solution of low nucleophilicity.It was also found that the kind of (Br)+ species formed anodically in the absence of the alcohols in dichloromethane celarly depended on charge(Q) passed as follows:Br3- at Q-1 (1F = 96480 C), Brn- (n>3) at 2/3-1, and Br2 at Q = 1F mol-1.Among these species, Br3- and Br2 seemed to be the weakest and strongest oxidizing agents, respectively.Lower efficiency for the direct electrooxidation in higher Br- concentration was rationalized as due to more predominant formation of Br3- and/or Brn- with smaller n values.
A highly efficient thiazolylidene catalyzed acetoin formation: Reaction, tolerance and catalyst recycling
Gu, Liuqun,Lu, Ting,Li, Xiukai,Zhang, Yugen
, p. 12308 - 12310 (2014)
An efficient formation of acetoin from acetaldehyde was achieved under thiazolylidene catalysis. High yields and TON were achieved. Its sufficient tolerance toward ethanol and moisture renders it a practical key step of the ethanol upgrading process. A new type of solid supported thiazolylidene catalyst was designed to make catalyst recycling achievable. This journal is
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Loeb,Pulvermacher
, p. 12 (1910)
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Selective hydrogenation by novel composite supported Pd egg-shell catalysts
Carrara,Badano,Betti,Lederhos,Rintoul,Coloma-Pascual,Vera,Quiroga
, p. 72 - 77 (2015)
Two organic-inorganic mixed phase supports were prepared, comprising an alumina filler and polymers of different chemical nature. Four low loaded Pd catalysts were prepared. Good activities and selectivities were obtained during the hydrogenations of styrene, 1-heptyne and 2,3-butanedione. The catalysts were found to have excellent mechanical properties and could be used in applications needing high attrition resistance and crushing strength. In this sense, processes for fine chemicals using slurry reactors or processes for commodities using long packed beds could advantageously use them.
Vapor-phase catalytic dehydration of 2,3-butanediol into 3-buten-2-ol over Sc2O3
Duan, Hailing,Yamada, Yasuhiro,Sato, Satoshi
, p. 1773 - 1775 (2014)
Vapor-phase catalytic dehydration of 2,3-butanediol (2,3-BDO) was investigated over rare earth oxide (REO) catalysts as well as In2O3. In the dehydration of 2,3-BDO, 3-buten-2-ol (3B2OL) was produced together with 3-hydroxy-2-butanone (3H2BO), butanone (MEK), 2-methylpropanal (IBA), 2-methyl-1-propanol (IBO), etc. Sc2O3 and In2O3 showed hi gher 3B2OL select ivities than other REOs. In particular, Sc2O3 converted 2,3-BDO into 3B2OL with an excellent selectivity of 85.0% at 99.9% conversion.
N-PEGylated Thiazolium Salt: A Green and Reusable Homogenous Organocatalyst for the Synthesis of Benzoins and Acyloins
Haghighi, Ali Javaheri,Mokhtari, Javad,Karimian, Khashayar
, p. 1646 - 1652 (2020/10/19)
N-PEGylated-thiazolium salt is used as efficient catalyst for the benzoin condensation. The catalyst was synthesized by reaction of activated polyethylene glycol 10,000 (PEG-10000) with 4-methyl-5-thiazoleethanol (sulfurol). Reaction mixture undergoes temperature-assisted phase transition and catalyst separated by simple filtration. After reaction course, catalyst can be recycled and reused without any apparent loss of activity which makes this process cost effective and hence ecofriendly. Synthesized benzoins and acyloins by this method have been characterized on the basis of melting point and 1H-NMR spectral studies. Graphic Abstract: [Figure not available: see fulltext.]
Sol-gel synthesis of ceria-zirconia-based high-entropy oxides as high-promotion catalysts for the synthesis of 1,2-diketones from aldehyde
Dinjar, Kristijan,Djerdj, Igor,Koj?inovi?, Jelena,Kukovecz, ákos,Markovi?, Berislav,Mileti?, Aleksandar,Nagy, Sándor Balázs,Sapi, Andras,Stenzel, David,Széchenyi, Aleksandar,Szenti, Imre,Tang, Yushu,Tatar, Dalibor,Varga, Gábor,Ziegenheim, Szilveszter
, (2021/10/20)
Efficient Lewis-acid-catalyzed direct conversion of aldehydes to 1,2-diketones in the liquid phase was enabled by using newly designed and developed ceria–zirconia-based high-entropy oxides (HEOs) as the actual catalysts. The synergistic effect of various cations incorporated in the same oxide structure (framework) was partially responsible for the efficiency of multicationic materials compared to the corresponding single-cation oxide forms. Furthermore, a clear, linear relationship between the Lewis acidity and the catalytic activity of the HEOs was observed. Due to the developed strategy, exclusively diketone-selective, recyclable, versatile heterogeneous catalytic transformation of aldehydes can be realized under mild reaction conditions.
Energy- And cost-effective non-sterilized fermentation of 2,3-butanediol by an engineered: Klebsiella pneumoniae OU7 with an anti-microbial contamination system
Guo, Ze-Wang,Ou, Xiao-Yang,Xu, Pei,Gao, Hui-Fang,Zhang, Liao-Yuan,Zong, Min-Hua,Lou, Wen-Yong
, p. 8584 - 8593 (2020/12/31)
Microbial contamination is a serious challenge that needs to be overcome for the successful biosynthesis of 2,3-butanediol (2,3-BD). However, traditional strategies such as antibiotic administration or sterilization are costly, have high energy demands, and may increase the risk of antibiotic resistance. Here, we intend to develop a robust strategy to achieve non-sterilized fermentation of 2,3-BD. Briefly, the robust strain can metabolize unconventional chemicals as essential growth nutrients, and therefore, outcompete contaminant microbes that cannot use unconventional chemicals. To this end, Klebsiella pneumoniae OU7, a robust strain, was confirmed to rapidly exploit urea and phosphite (unconventional chemicals) as the primary sources of nitrogen (N) and phosphorus (P), and withstand deliberate contamination in the possibly contaminated systems. Secondly, metabolic engineering, pathogenicity elimination and adaptive laboratory evolution were successively performed, endowing the best strain with an excellent fermentation performance for safe 2,3-BD production. Finally, 84.53 g L-1 of 2,3-BD was synthesized with a productivity of 1.17 g L-1 h-1 and a yield of 0.38 g g-1 under the non-sterilized system. In summary, our technique reduces labor and energy costs and simplifies the fermentation process because sterilization does not need to be performed. Thus, our work will be beneficial for the sustainable synthesis of 2,3-BD. This journal is