565-69-5Relevant articles and documents
Conversion of Propanal to Pentan-3-one using Lanthanide Oxides
Claridge, John B.,Green, Malcolm L. H.,Tsang, Shik Chi,York, Andrew P. E.
, p. 1089 - 1094 (1993)
The heterogeneous reaction between propanal vapour and rare-earth-metal oxides gives as major products pentan-3-one and carbon dioxide.Residence time investigations indicate that pentan-3-one and carbon dioxide are primary products.Deactivation and high-resolution electron microscopy studies support the hypothesis that surface participates in the reaction, and high oxygen mobilities in the oxide may allow defects to spread within the oxide.The carbon dioxide produced in the reaction poisons the lanthanum oxide leading to the faster deactivation and temperature-programmed desorption indicates the presence of a surface intermediate which decomposes to pentan-3-one and carbon dioxide.A mechanism is proposed in which the formation of pentan-3-one proceeds via surface-bound carboxylate species.Preliminary studies show that catalytic production of pentan-3-one can potentially be sustained by co-feeding water with propanal to the rare-earth-metal oxides.
Rational Design of a Metallocatalytic Cavitand for Regioselective Hydration of Specific Alkynes
Endo, Naoki,Inoue, Mami,Iwasawa, Tetsuo
supporting information, p. 1136 - 1140 (2018/03/13)
The synthesis of a functionalized supramolecular cavitand with inwardly oriented AuI and P=O moieties was explored, including its catalytic proclivity in the selective hydration of internal alkynes. The cavitand works as a supramolecular flask device: AuI coordinates to the triple bond, the P=O moiety connects with a H2O molecule, and the cavity favors folding of a single alkynyl side chain. Several tests of different substrate patterns indicated that the cavity was substrate specific, similar to enzymatic catalysis.
Selective Catalytic Hydration of Alkynes in the Presence of Au-Cavitands: A Study in Structure–Activity Relationships
Inoue, Mami,Ugawa, Katto,Maruyama, Tomoyuki,Iwasawa, Tetsuo
, p. 5304 - 5311 (2018/09/12)
The effects of the catalytic cavities in gold-functionalized cavitands in the hydration of internal alkynes have been studied. Variations on cavitand structures revealed the importance of two features that were studied: (1) flanking aromatic rings, and (2) an adjacent P=O moiety. The di-quinoxaline-spanned resorcin[4]arene system provides a well-defined compartment, in which a cationic Au ion activates an internal alkyne for conversion into a ketone by delivery of water that has also been activated, this time by a P=O moiety. We synthesized four variations on our parent cavitand. Variations of the cavitand walls include replacement of quinoxaline components with pyrazine or methylene units. Variation of the P=O center was accomplished with methylene or quinoxaline moieties. All variants displayed lower catalytic activity or selectivity, allowing us to confirm the significance both of an internal cavity and of an activation site for water.
Study on the degradation mechanism and pathway of benzene dye intermediate 4-methoxy-2-nitroaniline: Via multiple methods in Fenton oxidation process
Guo, Ying,Xue, Qiang,Cui, Kangping,Zhang, Jia,Wang, Hui,Zhang, Huanzhen,Yuan, Fang,Chen, Honghan
, p. 10764 - 10775 (2018/03/26)
Benzene dye intermediate (BDI) 4-methoxy-2-nitroaniline (4M2NA) wastewater has caused significant environmental concern due to its strong toxicity and potential carcinogenic effects. Reports concerning the degradation of 4M2NA by advanced oxidation process are limited. In this study, 4M2NA degradation by Fenton oxidation has been studied to obtain more insights into the reaction mechanism involved in the oxidation of 4M2NA. Results showed that when the 4M2NA (100 mg L-1) was completely decomposed, the TOC removal efficiency was only 30.70-31.54%, suggesting that some by-products highly recalcitrant to the Fenton oxidation were produced. UV-Vis spectra analysis based on Gauss peak fitting, HPLC analysis combined with two-dimensional correlation spectroscopy and GC-MS detection were carried out to clarify the degradation mechanism and pathway of 4M2NA. A total of nineteen reaction intermediates were identified and two possible degradation pathways were illustrated. Theoretical TOC calculated based on the concentration of oxalic acid, acetic acid, formic acid, and 4M2NA in the degradation process was nearly 94.41-97.11% of the measured TOC, indicating that the oxalic acid, acetic acid and formic acid were the main products. Finally, the predominant degradation pathway was proposed. These results could provide significant information to better understand the degradation mechanism of 4M2NA.
Regioselective Isomerization of 2,3-Disubstituted Epoxides to Ketones: An Alternative to the Wacker Oxidation of Internal Alkenes
Lamb, Jessica R.,Mulzer, Michael,Lapointe, Anne M.,Coates, Geoffrey W.
, p. 15049 - 15054 (2015/12/08)
We report an alternative pathway to the Wacker oxidation of internal olefins involving epoxidation of trans-alkenes followed by a mild and highly regioselective isomerization to give the major ketone isomers in 66-98% yield. Preliminary kinetics and isotope labeling studies suggest epoxide ring opening as the turnover limiting step in our proposed mechanism. A similar catalytic system was applied to the kinetic resolution of select trans-epoxides to give synthetically useful selectivity factors of 17-23 for benzyl-substituted substrates.
CONVERSION OF OXYGENATES TO HYDROCARBON FUELS BY DEOXYGENATION
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Page/Page column 32-33, (2011/10/10)
Oxygenates from biomass, particularly hydroxyl-substituted C2-plus hydrocarbons, are treated for removal of some or all of their oxygen atoms and for chain lengthening by carbon-carbon coupling in a single reaction medium in the gas phase over a solid catalyst.
Pheromone synthesis. Part 243: Synthesis and biological evaluation of (3R,13R,1′S)-1′-ethyl-2′-methylpropyl 3,13-dimethylpentadecanoate, the major component of the sex pheromone of Paulownia bagworm, Clania variegata, and its stereoisomers
Mori, Kenji,Tashiro, Takuya,Zhao, Boguang,Suckling, David M.,El-Sayed, Ashraf M.
experimental part, p. 2642 - 2653 (2010/05/18)
All of the four stereoisomers of (1′S)-1′-ethyl-2′-methylpropyl 3,13-dimethylpentadecanoate, the major component of the female sex pheromone of Clania variegata, were synthesized by employing olefin cross metathesis as the key reaction and starting from (R)- or (S)-2-methyl-1-butanol, (R)- or (S)-citronellal, and (S)-2-methyl-3-pentanol. Their bioassay revealed the (3R,13R,1′S)-isomer as the bioactive one, whose more efficient synthesis was achieved in two different ways by employing Wittig reaction as the key step.
Silica-supported HgSO4/H2SO4: A convenient reagent for the hydration of alkynes under mild conditions
Mello, Rossella,Alcalde-Aragonés, Ana,González-Nú?ez, María Elena
scheme or table, p. 4281 - 4283 (2010/09/07)
The silica-supported aqueous-phase catalyst (SAPC) approach has proven convenient for efficiently performing the hydration of alkynes with HgSO 4/H2SO4 to give the corresponding carbonyl compounds in dichloromethane under mild conditions. The use of this solid reagent significantly improves the reaction work-up as it merely involves filtering and evaporating the solvent.
Synthesis of all the four stereoisomers of (1′S)-1-ethyl-2-methylpropyl 3,13-dimethylpentadecanoate, the major component of the sex pheromone of Paulownia bagworm, Clania variegata
Mori, Kenji,Tashiro, Takuya
scheme or table, p. 3266 - 3269 (2009/09/05)
All the four stereoisomers of (1′S)-1-ethyl-2-methylpropyl 3,13-dimethylpentadecanoate, the major component of the sex pheromone of Clania variegata, were synthesized by starting from (R)- or (S)-2-methylbutan-1-ol, (R)- or (S)-citronellal, and (S)-2-methylpentan-3-ol. Olefin cross metathesis was employed as the key reaction.
Liquid-phase isomerization of saturated and unsaturated epoxides
Mel'nik,Khvatova,Moskvichev,Srednev,Egorova
, p. 167 - 169 (2007/10/03)
The liquid-phase isomerization of a variety of epoxides was studied using a complex catalyst system based on magnesium bromide and dimethylformamide. The data obtained elucidate the mechanism of the liquid-phase isomerization and show the range of oxygen-containing compounds which can be prepared through this reaction.