- One-pot synthesis of dimethyl succinate from D-fructose using Amberlyst-70 catalyst
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Dimethyl succinate (DMS), an important building block of bio-based platform chemicals, was produced from D-fructose under one-pot and metal-free conditions for the first time. In the presence of 1.5 mmol D-fructose, 75 mg Amberlyst-70 and 10 bar O2/
- He, Liangtu,Huang, Yuzhang,Len, Christophe,Liu, Lei,Miao, Xinge,Wang, Yantao,Yang, Weiran
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- 30. On the Regioselectivity Control in the Palladium-Catalyzed Hydro-alkoxycarbonylation of α,β-Unsaturated Esters
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The regioselectivity of the hydro-alkoxycarbonylation of methyl acrylate, methacrylate, and crotonate catalyzed by complexes (L = phosphine ligands) can be largely controlled by variation of the ligands.PPh3 promotes preferential carbonylation a
- Consiglio, Giambattista,Nefkens, Sylvia C. A.,Pisano, Carmelina,Wenzinger, Fritz
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- Semiconductor Photocatalysis: Visible Light Induced Photoreduction of Aromatic Ketones and Electron-deficient Alkenes catalysed by Quantised Cadmium Sulfide
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Colloidal CdS suspensions (CdS-0) prepared at 0 deg C from methanolic Cd(ClO4)2 and Na2S solutions consist of quantised CdS microcrystallites (2-5 nm) and their loose aggregates, which catalyse the effective photoreduction of aromatic ketones and electron-deficient alkenes with triethylamine as electron donor.Under visible light induced photolysis, the methanolic CdS-0 suspension becomes brown owing to the reduction of lattice Cd2+ to Cd0, leading to the effective formation of alcohols from ketones, and dihydro compounds from alkenes.With the reduction potential2-) in the CdS-0 system, however, suppresses the formation of lattice Cd0, inducing one-electron transfer photoreductions which result in the exclusive formation of pinacols and 1,2,3,4-tetra(methoxycarbonyl)butane from the respective ketones and dimethyl maleate.The relationship between the two-electron reductions and the photogenerated lattice Cd0 is discussed in terms of the regulation of semiconductor photocatalysis.
- Shiragami, Tsutomu,Ankyu, Hirofumi,Fukami, Shinako,Pac, Chyongjin,Yanagida, Shozo,et al.
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- Selective monomethyl esterification of linear dicarboxylic acids with bifunctional alumina catalysts
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An environmentally friendly protocol for the selective protection of dicarboxylic acids is reported using methanol as a cheap esterifying agent and alumina as a heterogeneous catalyst; the selectivity of the process has been ascribed to a balanced acidity/basicity of the bifunctional alumina catalyst.
- Santacroce, Veronica,Bigi, Franca,Casnati, Alessandra,Maggi, Raimondo,Storaro, Loretta,Moretti, Elisa,Vaccaro, Luigi,Maestri, Giovanni
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- Selective hydrogenation by polymer-encapsulated platinum nanoparticles prepared by an easy single-step sonochemical synthesis
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Polypyrrole-encapsulated platinum nanoparticles (PPy/Pt-NPs) prepared by an easy single-step sonochemical synthesis were used as catalysts for the liquid phase hydrogenation of substituted alkenes in methanol or methanol/water mixtures. Polypyrrole (PPy) coatings on the nanoparticles were able to act as nanoscopic filters for substrates molecules, and consequently substrate selectivity could be controlled in the catalytic processes.
- Atobe, Mahito,Okamoto, Mayuko,Fuchigami, Toshio,Park, Jong-Eun
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- Oxidative carbonylation of ethene catalyzed by Pd(II)-PPh3 complexes in MeOH using benzoquinone as stoichiometric oxidant
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The complexes [Pd(COOMe)nX2-n(PPh3) 2] (n = 0, 1, 2; X = TsO, OAc, ONO2, Cl, Br), [Pd(SO 4)(PPh3)2], [PdCl2(PPh 3)]2 and PdX2 (X = Cl, Br, I) catalyze the oxidative ethene carbonylation in MeOH using benzoquinone (BQ) as stoichiometric oxidant. The main products dimethyl succinate (DMS) and dimethyl oxalate (DMO) are formed together with minor amounts of methyl propanoate and dimethyl carbonate. The formation of DMS unambiguously proves that ethene inserts into a Pd-COOMe bond. The influence of the CO/ethene ratio at constant total pressure and of the BQ/Pd ratio on the product distribution has been studied. Model reactions of a Pd-hydride with BQ, of trans-[Pd(COOMe)(TsO)(PPh 3)2] with ethene in the presence of BQ and of trans-[Pd(COOMe)2(PPh3)2] with BQ have been studied by 31P{1H} NMR. BQ consumes the Pd-hydride and directs the catalysis toward a Pd-COOMe initiator leading to DMS. In the catalysis to DMO, BQ is likely to favour the formation of a Pd-(COOMe) 2 species having the two carbomethoxy ligands in vicinal position such to favour the elimination of the product. The proposed catalytic cycles for the formation of the products are discussed.
- Cavinato, Gianni,Facchetti, Sarah,Toniolo, Luigi
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- Promoted role of Cu(NO3)2 on aerobic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran over VOSO4
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The promoted effect of Cu(NO3)2 on aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) catalyzed by VOSO4 in acetonitrile was intensively investigated. It was revealed that Cu(NO3)2 facilitated the activation of VOSO 4 to generate active V5+ species via the generation of NOx gas. The high DFF selectivity is ascribed to Cu2+ cation which can effectively prohibit oxidative CC bond cleavage reaction of HMF and prevent radical reaction of DFF to humins. In addition, the polarity of solvent plays a great role on high selectivity of DFF.
- Jia, Xiuquan,Ma, Jiping,Wang, Min,Du, Zhongtian,Lu, Fang,Wang, Feng,Xu, Jie
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- Conversion of levulinate into succinate through catalytic oxidative carbon-carbon bond cleavage with dioxygen
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Grand Cleft Oxo: Levulinate, available from biomass, is oxidized into succinate through manganese(III)-catalyzed selective cleavage of C-C bonds with molecular oxygen. In addition to levulinate, a wide range of aliphatic methyl ketones also undergo oxidative C-C bond cleavage at the carbonyl group. This procedure offers a route to valuable dicarboxylic acids from biomass resources by nonfermentive approaches. Copyright
- Liu, Junxia,Du, Zhongtian,Lu, Tianliang,Xu, Jie
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- Kinetics of citraconic anhydride formation via condensation of formaldehyde and succinates
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Formation of citraconic anhydride via condensation of succinic acid and its derivatives with formaldehyde is carried out over γ-alumina catalyst in a continuous fixed-bed reactor. Dimethyl succinate and Formalin (37 wt % formaldehyde, 10 wt % methanol in water) are the preferred feed materials for the reaction; catalyst activity is sustained with Formalin relative to that with other formaldehyde sources such as trioxane or Formcel, because the water in Formalin inhibits coke formation. With this feed combination, a total citraconate yield of 31% of theoretical with 72% selectivity is achieved at a weight hour space velocity of 0.9 kg of succinate/kg of catalyst/h, a succinate to formaldehyde molar feed ratio of 1:2, and a temperature of 380 °C. The reaction is free from mass transfer limitations at these conditions. A kinetic model is presented that describes product distributions and reactant conversion as a function of space velocity and temperature. The reaction system is part of an overall process to produce itaconic acid from renewable resource-based succinic acid.
- Shekhawat, Dushyant,Nagarajan, Kirthivasan,Jackson, James E.,Miller, Dennis J.
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- Kinetic Isotope Effects and Pressure Effects in Several Hydrogen-Transfer Reactions of Tetralin and Related Compounds
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The H/D kinetic isotope effects and activation volumes have been measured for several hydrogen-transfer reactions using tetralin, dihydronaphthalenes, cyclohexa-1,4-diene, and cyclohexanol as donors.The isotope effects were found to exhibit different patterns for reactions of different mechanisms.They indicate whether hydrogen is in transit in the activated complex and show the number of atoms in transit (one or two).The KIE for the reaction of tetralin with quinones is consistent with concerted transfer of two hydrogens whereas the other reactions were found to be stepwise.The activation volumes lie within the range -23 to -33 mL/mol and do not seem to differetiate among bimolecular mechanisms.The relevance to previous studies of the KIE and ΔV(excit.) for coal hydrogenation reactions is discussed.
- Pajak, Janusz,Brower, K. R.
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- Catalytic oxidative C-C bond cleavage route of levulinic acid and methyl levulinate
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Recently, obtaining value-added chemicals from biomass resources has attracted considerable attention. Levulinic acid is one of the most important biomass platform compounds, which could be obtained from carbohydrate biomass. In this work, levulinic acid was selectively converted into C4 product, including succinic anhydride, via catalytic oxidation with a manganese catalyst in acetic anhydride. Moreover, an unexpected product of maleic anhydride was obtained, which greatly differs from that of levulinate ester. The pathway for formation of maleic anhydride was studied by monitoring and confirming intermediates α-angelica lactone and its derivative 2-methyl-5-oxotetrahydro-2-furanyl acetate. Based on the obtained mechanistic information, the different behaviour between the oxidative cleavage of levulinic acid and levulinate ester was further discussed.
- Xia, Fei,Du, Zhongtian,Liu, Junxia,Ma, Yangyang,Xu, Jie
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- Ozonolysis of Olefins, V : Emulsion Ozonization of Methyl Linoleate and Methyl Linolenate in Aqueous Alkaline Hydrogen Peroxide
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The ozonolysis of methyl linoleate and methyl linolenate in neutral and alkaline aqueous emulsions of hydrogen peroxide was investigated.Besides the expected products such as dimethyl malonate (3b), dimethyl azelate (3h) and methyl hexanoate (2a) further homologous methyl esters of dicarboxylic acids (3a-g), oxo carboxylic acids (4a, b, e-h) and hydroxy carboxylic acids (4c, d) could be detected by GC/MS analysis.Furthermore a method for separation of 8-hydroxyoctanoic acid (4d) by methylation and extraction of the reaction mixture containing the ozonolysis products is described. Keywords.Ozonization; Fatty esters; 8-Hydroxyoctanoic acid.
- Poklukar, Norbert,Mittelbach, Martin
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- Electroreductive hydrogenation of activated olefins using the concept of site isolation
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Electroreductive hydrogenation of activated olefins was investigated using the concept of site isolation. It was shown by electrochemical measurements as well as preparative electrolyses that the use of silica gel-supported sulfonic acid (Si-SO3H) promotes the protonation step in electroreductive hydrogenation of activated olefins without electroreductive destruction at the cathode. On the basis of the concept of site isolation, electroreductive hydrogenation of several activated olefins was successfully carried out to provide the corresponding hydrogenation products in high yields.
- Tomida, Shinsuke,Tsuda, Ryohei,Furukawa, Shiho,Saito, Marie,Tajima, Toshiki
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- Chemical Reaction Monitoring using Zero-Field Nuclear Magnetic Resonance Enables Study of Heterogeneous Samples in Metal Containers
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We demonstrate that heterogeneous/biphasic chemical reactions can be monitored with high spectroscopic resolution using zero-field nuclear magnetic resonance spectroscopy. This is possible because magnetic susceptibility broadening is negligible at ultralow magnetic fields. We show the two-step hydrogenation of dimethyl acetylenedicarboxylate with para-enriched hydrogen gas in conventional glass NMR tubes, as well as in a titanium tube. The low frequency zero-field NMR signals ensure that there is no significant signal attenuation arising from shielding by the electrically conductive sample container. This method paves the way for in situ monitoring of reactions in complex heterogeneous multiphase systems and in reactors made of conductive materials while maintaining resolution and chemical specificity.
- Blanchard, John W.,Budker, Dmitry,Burueva, Dudari B.,Eills, James,Garcon, Antoine,Koptyug, Igor V.,Kovtunov, Kirill V.,Picazo-Frutos, Román
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- HYDROGENOLYSIS OF CARBON-FLUORINE BONDS IN CATALYTIC HYDROGENATION. II
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The extreme readiness of replacement of fluorine by hydrogen in catalytic hydrogenations of fluoro- and difluorobutenedioic acids and their esters is believed to be caused by participation of double bonds in the hydrogenation processes.The mechanism of the hydrogenolysis suggested in the previous paper has been tested using deuterium and its mixtures with hydrogen for the reductions.Based on the results the mode of participation of the double bond has been modified to comply with the experimental evidence. 1H, 2H and 19F NMR spectra of the deuterated products are presented and interpreted.
- Hudlicky, Milos
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- An environmentally friendly electrolytic system based on the acid-base reaction between water and solid-supported bases
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We have developed an environmentally friendly electrolytic system based on the acid-base reaction between water and solidsupported bases. Furthermore, we have successfully applied the electrolytic system to a flow cell. Copyright
- Tajima, Toshiki,Ishino, Satomi,Kurihara, Hitoshi
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- Acid-catalyzed conversion of xylose in methanol-rich medium as part of biorefinery
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Acid treatments of xylose have been performed in a methanol/water mixture to investigate the reaction pathways of xylose during bio-oil esterification. Xylose was mainly converted into methyl xylosides with negligible humins formed below 130°C. However, humins formation became significant with the dehydration of xylose to furfural and 2-(dimethoxymethyl)furan (DOF) at elevated temperatures. The conversion of xylose to methyl xylosides protected the C1 hydroxyl group of xylose, which stabilized xylose and suppressed the formation of sugar oligomers and polymerization reactions. In comparison, the conversion of furfural to DOF protected the carbonyl group of furfural. However, the protection did not remarkably suppress the polymerization of furfural at high temperatures because of the shift of the reaction equilibrium from DOF to furfural with a prolonged residence time. In addition, the acid treatment of furfural produced methyl levulinate in methanol and levulinic acid in water, which was catalyzed by formic acid. Copyright
- Hu, Xun,Lievens, Caroline,Li, Chun-Zhu
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- Understanding the solvent effect on the catalytic oxidation of 1,4-butanediol in methanol over Au/TiO2 catalyst: NMR diffusion and relaxation studies
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The effect of water on the catalytic oxidation of 1,4-butanediol in methanol over Au/TiO2 has been investigated by catalytic reaction studies and NMR diffusion and relaxation studies. The addition of water to the dry catalytic system led to a decrease of both conversion and selectivity towards dimethyl succinate. Pulsed-field gradient (PFG)-NMR spectroscopy was used to assess the effect of water addition on the effective self-diffusivity of the reactant within the catalyst. NMR relaxation studies were also carried out to probe the strength of surface interaction of the reactant in the absence and presence of water. PFG-NMR studies revealed that the addition of water to the initial system, although increasing the dilution of the system, leads to a significant decrease of effective diffusion rate of the reactant within the catalyst. From T1 and T2 relaxation measurements it was possible to infer the strength of surface interaction of the reactant with the catalyst surface. The addition of water was found to inhibit the adsorption of the reactant over the catalyst surface, with the T1/T2 ratio of 1,4-butanediol decreasing significantly when water was added. The results overall suggest that both the decrease of diffusion rate and adsorption strength of the reactant within the catalyst, due to water addition, limits the access of reactant molecules to the catalytic sites, which results in a decrease of reaction rate and conversion. Copyright
- D'Agostino, Carmine,Brett, Gemma L.,Miedziak, Peter J.,Knight, David W.,Hutchings, Graham J.,Gladden, Lynn F.,Mantle, Mick D.
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- Conformational characteristics and configurational properties of poly(ethylene succinate) and poly(butylene succinate) and structure-property-function relationships of representative biodegradable polyesters
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Conformational characteristics and configurational properties of synthetic biodegradable polyesters, poly(ethylene succinate) and poly(butylene succinate), have been investigated by NMR experiments and molecular orbital calculations on their model compounds and the rotational isomeric state calculations for the two aliphatic polyesters. The results have been related to their crystal structures and thermal properties and compared with those obtained previously for poly((R)-3-hydroxybutyrate) and poly(lactic acid) to elucidate structureeproperty relationships of the representative biodegradable polyesters. In addition, selective affinities to degradative enzymes of the four polyesters have been satisfactorily explained in terms of their conformational characteristics and interactions with the depolymerases.
- Sasanuma, Yuji,Nonaka, Yuta,Yamaguchi, Yuki
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- Polarization transfer from para-hydrogen to heteronuclei: Effect of H/D substitution. the case of AA′X and A2A2′X spin systems
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Upon hydrogenation from para-hydrogen (p-H2), hyperpolarization transfer toward a heteronucleus may be possible even if the two protons are chemically equivalent in the final product (but not magnetically equivalent), provided that J couplings with the heteronucleus exist. It is however shown (theoretically and experimentally) that this transfer effectively occurs if the spin system in the hydrogenated molecule is of the type AA′X (A and A′ denoting the two protons originating from p-H2 and X the heteronucleus) but does not occur for a spin system of the A2A2′X type. A theory has been worked out for assessing the details of the X spectrum (multiplet patterns) in the case of ALTADENA and PASADENA experiments. Experimental verifications are provided.
- Aime, Silvio,Gobetto, Roberto,Reineri, Francesca,Canet, Daniel
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- Efficient palladium catalysts for the copolymerization of carbon monoxide with olefins to produce perfectly alternating polyketones
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A class of highly efficient homogeneous palladium catalyst systems has been developed for the production of perfectly alternating copolymers of carbon monoxide with ethylene.Mixtures of carbon monoxide, ethylene and propene are converted into the correspo
- Drent, E.,Broekhoven, J.A.M. van,Doyle, M.J.
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- Conversion of succinic acid to 1,4-butanediol via dimethyl succinate over rhenium nano-catalyst supported on copper-containing mesoporous carbon
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Copper-containing mesoporous carbons (XCu-MC) with different copper content (X = 8.0, 12.7, 15.9, 23.3, and 26.8 wt%) were prepared by a single-step surfactant-templating method. Rhenium nano-catalysts supported on copper-containing mesoporous carbons (Re/XCu-MC) were then prepared by an incipient wetness method. Re/XCu-MC (X = 8.0, 12.7, 15.9, 23.3, and 26.8 wt%) catalysts were characterized by nitrogen adsorption-desorption isotherm, HR-TEM, FT-IR, and H2- TPR analyses. Liquid-phase hydrogenation of succinic acid to 1,4-butanediol (BDO) via dimethyl succinate (DMS) was carried out over Re/XCu-MC catalysts in a batch reactor. The effect of copper content on the physicochemical properties and catalytic activities of Re/XCu-MC catalysts in the hydrogenation of succinic acid to BDO was investigated. Re/XCu-MC catalysts retained different physicochemical properties depending on copper content. In the hydrogenation of succinic acid to BDO, yield for BDO showed a volcano-shaped trend with respect to copper content. Thus, an optimal copper content was required to achieve maximum catalytic performance of Re/XCu-MC. It was also observed that yield for BDO increased with increasing the amount of hydrogen consumption by copper in the Re/XCu-MC catalysts.
- Hong, Ung Gi,Kim, Jeong Kwon,Lee, Joongwon,Lee, Jong Kwon,Yi, Jongheop,Song, In Kyu
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- Oxidative degradation of nylon-6 and nylon-6,6 with nitrogen dioxide in supercritical carbon dioxide
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Nylon-6 and nylon-6,6 were subjected to oxidative degradation with NO 2 in supercritical CO2. It was found that valuable short-chain α,ω-diacid mixture could be obtained in good yield under relatively mild conditions. Copyright
- Yanagihara, Naohisa,Abe, Naoto,Takama, Hironori,Shimamura, Yuichiro,Yoshida, Masaaki
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- Isotopomeric diols by "one-pot" Ru-catalyzed homogeneous hydrogenation of dicarboxylic acids
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The "one-pot" homogeneous hydrogenation of γ-butyrolactone and succinic or fumaric acid to 1,4-butandiol, have been successfully realized in the presence of the catalytic system [Ru(acac)3]/triphos] [triphos:MeC(CH2PPh2)3]. The influence of some reaction parameters on the regioselectivity and the rate of the reaction were investigated. The study was then extended to the "one-pot" synthesis of isotopomeric 1,4-butandiols by deuteration of the appropriate substrates in a deuterated solvent. 1,4-butandiol-d8, which was fully characterized, was obtained with 96% yield and 100% isotopomeric selectivity. A mechanism was proposed to rationalize the role of catalyst, solvent and deuterium distribution.
- Rosi, Luca,Frediani, Marco,Frediani, Piero
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- Electrosynthesis of esters of mono- and dioxoalkanoic and alkanedioic acids on the basis of nitro-substituted alkyl carboxylates and cycloalkanones
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A one-pot electrochemical method for the synthesis of methyl monooxoalkanoates with the carbonyl group in position 4, methyl dioxoalkanoates with the oxo groups in positions 4,7-, 6,9-, 7,10-, and 12,15, and methyl 4-oxoalkanedioates was developed. This method is based on amperostatic electrolysis in an undivided cell of the salts of esters of nitroalkanoic acids and their adducts with CH2=CHX (X = Ac, CO2Me).
- Ogibin,Ilovaiskii,Merkulova,Nikishin
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- Kinetics of esterification of succinic anhydride with methanol by homogeneous catalysis
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Kinetic data on the esterification of succinic anhydride with methanol catalyzed by sulfuric acid have been obtained using a stirred batch reactor. In addition to get a precise ascertainment of the parameters the esterification of monomethyl succinate with methanol has been studied separately. Several experiments have been carried out with different initial molar ratios and different amounts of sulfuric acid at various temperatures. The conversion to dimethyl succinate at 30-65°C follows a first-order rate expression with respect to each component. A theoretical rate equation is derived by the following reaction mechanism: (1) succinic anhydride is protonated by sulfuric acid to form a reaction intermediate, (2) irreversible esterification to monomethyl succinate, (3) protonation of the monoester, and (4) the esterification to dimethyl succinate proceeds reversibly. The resultant kinetic equation fitted the experimental data quite well and is given by the expression: dcCH(3)OH÷dt = cH(2)SO(4) [ - 4.344 × 108e-65239/RT cC(4)H(4)O(3)cCH(3)OH - 2.457 × 106e-57732/RT cC(5)H(8)O(4)cCH(3)OH + 229e-34361/RT cC(6)H(10)O(4)cH(2)O]
- Bart,Reidetschlager,Schatka,Lehmann
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- Renewable Polyethers via GaBr3-Catalyzed Reduction of Polyesters
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Herein, a novel approach is reported for the synthesis of medium- and long-chain aliphatic polyethers 2 based on the GaBr3-catalysed reduction of polyesters 1 with TMDS as the reducing agent. Thus, various linear and branched aliphatic polyesters 1 were prepared and systematically investigated for this reduction strategy, demonstrating the applicability and versatility of this new polyether synthesis protocol. Medium- and long-chain chain polyethers were obtained from the respective polyesters without or with minor chain degradation, whereas short-chain polyesters, such as poly-l-lactide 1 i and poly[(R)-3-hydroxybutanoate] 1 j, showed major chain degradation. In this way, previously unavailable and uncommon polyethers were obtained and studied.
- Dannecker, Patrick-Kurt,Biermann, Ursula,von Czapiewski, Marc,Metzger, Jürgen O.,Meier, Michael A. R.
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- Chemical synthesis of fully biomass-based poly(butylene succinate) from inedible-biomass-based furfural and evaluation of its biomass carbon ratio
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We have produced fully biomass-based poly(butylene succinate) (PBS) from furfural produced from inedible agricultural cellulosic waste. Furfural was oxidized to give fumaric acid. Fumaric acid was hydrogenated under high pressure with a palladium-rhenium/carbon catalyst to give 1,4-butanediol, and with a palladium/carbon catalyst to give succinic acid. Dimethyl succinate was synthesized from fumaric acid by esterification and hydrogenation under normal pressure. Fully biomass-based PBS was obtained by polycondensation of biomass-based 1,4-butanediol and biomass-based succinic acid or dimethyl succinate. The biomass carbon ratio calculated from 14C concentrations measured by accelerator mass spectroscopy (AMS) verified that the PBS obtained in this study contained only biomass carbon. The polycondensation of biomass-based 1,4-butanediol and petroleum-based terephthalic acid or dimethyl terephthalate gave partially biomass-based poly(butylene terephthalate), which is an engineering plastic.
- Tachibana, Yuya,Masuda, Takashi,Funabashi, Masahiro,Kunioka, Masao
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- Photophysical Properties and Heterogeneous Photoredox Catalytic Activities of Ru(bpy)3@InBTB Metal–Organic Framework (MOF)
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Metal–organic frameworks (MOFs) with negatively charged frameworks are suitable for selectively encapsulating cationic guest ions via a cation-exchange process. Encapsulating photoactive [RuL3]2+ polypyridine complexes into the preorganized mesoscale channels of a MOF is a good method for stabilizing the excited states of the complexes. Three new RuL3@InBTB MOFs were prepared by encapsulating cationic [Ru(bpy)3]2+ (bpy=2,2′-bipyridine), [Ru(phen)3]2+ (phen=1,10-phenanthroline), and [Ru(bpz)3]2+ (bpz=2,2′-bipyrazine) into the mesopores of a three-dimensional (3D) InBTB MOF (H3BTB=1,3,5-benzenetribenzoic acid). The photophysical properties of the resulting materials were investigated by photoluminescence (PL) analysis. The photoredox catalytic activities were also investigated for the aza-Henry reaction, hydrogenation of dimethyl maleate, and decomposition of methyl orange under visible light irradiation at room temperature. RuL3@InBTB MOFs were found to be very stable and highly recyclable photoredox catalytic systems.
- Choi, In-Hwan,Yoon, Sukbin,Huh, Seong,Kim, Sung-Jin,Kim, Youngmee
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- Gold-nanoparticle-based catalysts for the oxidative esterification of 1,4-butanediol into dimethyl succinate
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The oxidation of 1,4-butanediol and butyrolactone have been investigated by using supported gold, palladium and gold-palladium nanoparticles. The products of such reactions are valuable chemical intermediates and, for example, can present a viable pathway for the sustainable production of polymers. If both gold and palladium were present, a significant synergistic effect on the selective formation of dimethyl succinate was observed. The support played a significant role in the reaction, with magnesium hydroxide leading to the highest yield of dimethyl succinate. Based on structural characterisation of the fresh and used catalysts, it was determined that small gold-palladium nanoalloys supported on a basic Mg(OH)2 support provided the best catalysts for this reaction. Twice as nice: The oxidation of 1,4-butanediol and butyrolactone has been investigated over supported gold, palladium and gold-palladium nanoparticles. The oxidation of both hydroxyl groups of α,γ-diols has previously proved to be difficult. Small AuPd alloy nanoparticles on a basic Mg(OH)2 support provide the best catalysts for this reaction. Copyright
- Brett, Gemma L.,Miedziak, Peter J.,He, Qian,Knight, David W.,Edwards, Jennifer K.,Taylor, Stuart H.,Kiely, Christopher J.,Hutchings, Graham J.
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- TRANSFORMATIONS OF DIETHYL PHOSPHITE IN THE PRESENCE OF Mn2(CO)10
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Upon heating with Mn2(CO)10-BrR systems, diethyl phosphite is partially converted to (EtO)3P(O).Evidence is given for a radical complex mechanism for these transformations.
- Moskalenko, M. A.,Kardanov, N. A.,Terent'ev, A. B.,Godovikov, N. N.
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- New secondary metabolites from croton sparsiorus morong
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Sparsioamide (1), a new sphingolipid, and sparsioside (2), a new diglyceride galactoside, have been isolated from the ethyl acetate soluble fraction of the 80% ethanolic extract of the whole plant of Croton sparsiorus Morong. Their structures were assigned by 1 H- and 13C-NMR spectra and DEPT, COSY, NOESY, HMQC, HMBC, and ESI-MS experiments. TUeBITAK.
- Mehmood, Rashad,Bibi, Amna,Malik, Abdul
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- The fabrication and characterization of a supramolecular Cu-based metallogel thin-film based Schottky diode
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In the present study, a stable supramolecular Cu(ii)-metallogel has been synthesized based on copper(ii) acetate monohydrate and succinic acid, engineered as a low-molecular-weight organic gelator. The mechanical assets of the Cu-H4L metallogel have been explored through a rheological investigation. Further, the aggregation of the synthesized metallogel has been well establishedviaseveral experiments using Job plots and ESI-MS. Apart from this, the morphology of the synthesized supramolecular metallogel was scrutinizedviaFESEM, TEM, and AFM studies, revealing the self-assembled thread-like morphology of the Cu-H4L metallogel. The functional group, elemental composition, crystalline behaviour, and thermal stability of the Cu-H4L metallogel were probedviaFT-IR, XPS, P-XRD, and TGA studies, respectively. The optical properties of the Cu-H4L metallogel reflected its semiconducting nature. Thus, based on the semiconducting properties of the Cu-H4L metallogel, we have successfully fabricated an active electronic device: a ‘Schottky diode’.
- Kumar, Vivek,Upadhyay, Rishibrind Kumar,Bano, Daraksha,Chandra, Subhash,Kumar, Deepak,Jit, Satyabrata,Hasan, Syed Hadi
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- High activity and selectivity of Ag/SiO2 catalyst for hydrogenation of dimethyl oxalate
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Ag/SiO2 prepared by a sol-gel process is highly effective for selective gas-phase hydrogenation of dimethyl oxalate to corresponding alcohols. The catalysts are of great potential as industrially viable and novel catalysts for the production of methyl glycolate and ethylene glycol.
- Yin, Anyuan,Guo, Xiaoyang,Dai, Weilin,Fan, Kangnian
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- Addition of halogenoacetic esters to aldehydes and ketones in the presence of Fe(CO)5
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The use of complex-forming solvents and variations in the reaction temperature made it possible to prepare α-halogeno β-hydroxy carboxylic esters upon addition of halogenoacetic esters to aldehydes and ketones promoted by iron pentacarbonyl.
- Terentiev,Vasilieva,Kuz'mina,Chakhovskaya,Brodsky,Belokon'
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- Visible-Light-Induced Two-Electron-Transfer Photoreductions on CdS: Effeects of Morphology
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Freshly prepared CdS suspensions (CdS-0) consisting of quantized particles and their loose aggregation catalyze photoreductions of aromatic ketones and olefins in methanol under visible light irradiation using triethylamine as sacrificial electron donor, yielding alcohols and dihydro compounds, respectively, which are more selective than photocatalysis of commercially available crystalline CdS (Aldrich) (CdS-Ald).Deuterium incorporation experiments in photolysis of dimethyl maleate in methanol-O-D revealed that CdS-0 catalyzes sequental two-electron-transfer photoreduction, affording dideuterated dimethyl succinate, while CdS-Ald induces both photoreduction and photoisomerization through disproportionation between one-electron-transfer-reduction intermediates, yielding much trideuterated dimethyl succinate and monodeuterated dimethyl fumarate and maleate.
- Shiragami, Tsutomu,Pac, Chyongjin,Yanagida, Shozo
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Read Online
- Methylation of mono- and dicarboxylic acids with dimethyl carbonate catalyzed with binder-free zeolite NaY
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Synthesis of methyl mono- and dicarboxylates was developed consisting in treating the corresponding acids with dimethyl carbonate in the presence of a heterogenic catalyst, crystalline aluminosilicate whose mechanically strong granules to 90–95% were built of crystal aggregates of zeolite Y with modulus of about 5.0 in the Na-form. Optimum catalyst and reagents ratio and the reaction conditions were found for the preparation in high yields of methyl esters of mono- and dicarboxylic acids.
- Khusnutdinov,Shchadneva,Mayakova, Yu. Yu.,Konovalova, Yu. S.,Khazipova,Kutepov
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Read Online
- Selective Alkene Insertion into Inert Hydrogen-Metal Bonds Catalyzed by Mono(phosphorus ligand)palladium(0) Complexes
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Isolated mono(phosphorus ligand)palladium(0) complexes catalyzed alkene insertions into hydrogen-tungsten bonds. These insertions using WHCp(CO)3 with ethyl acrylate and dimethyl fumarate smoothly gave the corresponding alkyltungsten complexes. Kinetic studies involving the stoichiometric reactions and DFT calculations suggest the following steps: (i) formation of a mono(phosphorus ligand)mono(alkene)palladium(0) species, (ii) subsequent reaction of a metal hydride with the palladium(0), (iii) insertion of the coordinated alkene into the resulting palladium hydride, and (iv) reductive elimination between the alkyl and metal on the palladium center to release the alkylmetal species with regeneration of a palladium(0) by a reaction with alkene.
- Komine, Nobuyuki,Ito, Ryo,Suda, Hiromi,Hirano, Masafumi,Komiya, Sanshiro
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Read Online
- Palladium nanodendrites uniformly deposited on the surface of polymers as an efficient and recyclable catalyst for direct drug modification via Z-selective semihydrogenation of alkynes
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The preparation of new monodisperse polycrystalline palladium nanoparticles uniformly distributed on the surface of polymers, by simply adding a palladium(ii) solution in water to the polymers, is described. The polymer supported palladium nanoparticles material was used as an efficient portable and reusable catalyst for the stereoselective semihydrogenation reaction of internal alkynes to (Z)-alkenes in green solvents.
- García-Calvo, José,Calvo-Gredilla, Patricia,Vallejos, Saúl,García, José Miguel,Cuevas-Vicario, José Vicente,García-Herbosa, Gabriel,Avella, Manuel,Torroba, Tomás
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Read Online
- The oxidation of primary alcohols to methyl esters and diols to lactones using trichloroisocyanuric acid
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Primary alcohols and diols are easily oxidized to methyl esters by a solution of trichloroisocyanuric acid with methyl alcohol in dichloromethane. In addition, α,ω-diols are also readily oxidized into lactones by refluxing with trichloroisocyanuric acid and pyridine in dichloromethane.
- Hiegel, Gene A.,Gilley, Cynthia B.
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Read Online
- Oxidation of cyclohexanone and/or cyclohexanol catalyzed by Dawson-type polyoxometalates using hydrogen peroxide
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The oxidation of cyclohexanone, cyclohexanol or cyclohexanone/cyclohexanol mixture using as catalyst, Dawson-type polyoxometalates (POMs) of formula, α- and β-K6P2W18O62, α-K6P2Mo6W12O62 and α1-K7P2Mo5VW12O62 and hydrogen peroxide, carried out at 90 °C with a reaction time of 20 h, led to a high number of mono- and di-acids which were identified by GC-MS. Levulinic, 6-hydroxyhexanoic, adipic, glutaric and succinic acids, major products were evaluated by HPLC. Regardless of the substrate nature, all POMs exhibited high catalytic activity with 94–99% of conversion, whereas the formation of the different products is sensitively related to both the composition and symmetry of the POMs and the substrate nature. The main products are adipic acid in the presence of α-K6P2Mo6W12O62 and α1-K7P2Mo5VW12O62, levulinic acid in the presence of α1-K7P2Mo5VW12O62 and β-K6P2W18O62 and 6-hydroxyhexanoic acid in the presence of α- and β-K6P2W18O62. Graphical abstract: High catalytic activity was observed with?α- and?β-K6P2W18O62, α-K6P2Mo6W12O62 and α1-K7P2Mo5VW12O62 Dawson-type for the oxidation of cyclohexanone, cyclohexanol or cyclohexanone/cyclohexanol mixture, in the hydrogen peroxide presence, to several oxygenated products. Adipic, levulinic and 6-hydroxyhexanoic acids are the main products. The peroxo- species formed in situ could be the active sites.[Figure not available: see fulltext.]
- Dermeche, Leila,Idrissou, Yasmina,Mazari, Tassadit,Moudjahed, Mohammed,Rabia, Cherifa
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- FLOW CHEMISTRY SYNTHESIS OF ISOCYANATES
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The disclosure provides, inter alia, safe and environmentally-friendly methods, such as flow chemistry, to synthesize isocyanates, such as methylene diphenyl diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and tetramethylxylene diisocyanate.
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Paragraph 0175; 0240-0242
(2021/06/22)
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- Biomass-derived dibasic acids to diesters with inorganic ligand-supported catalyst: synthesis, optimization, characterization
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Several attempts have been made to obtain aliphatic dicarboxylic diesters from esterification reaction to develop the biomass-derived platform molecules and green manufacturing processes. In this paper, Na3(H2O)6[AlMo6O18(OH)6], an Anderson-type polyoxometalate, firstly, was reported as a catalyst for diester synthesis from dicarboxylic acid to diester which showed an well productivity and selectivity characterized by 1H and 13C. Response surface methodology (RSM) integrated with the desirability function approach was used to determine the best operative conditions, and the optimal reaction parameters for maximum dipropyl succinate yield (77 ± 2.5%) were identified as 1.19?mol.% catalyst loading, 4.9:1 propanol/succinic acid ratio, 113?°C, and 9.6?h. Three batches of tests were carried for catalyst recycling with 78–75% yield even after 6 cycles of esterification. In addition, the substrate carbon chain was increased for investigation of substrate scope achieving satisfactory results and all products were characterized by 1H and 13C nuclear magnetic resonance spectroscopy.
- Chen, Zhe,Han, Sheng,Lu, Deli,Xu, Yumeng
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- Environment-friendly production method for greatly reducing sewage discharge of dimethyl succinylsuccinate
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The invention provides an environment-friendly production method for greatly reducing sewage discharge of dimethyl succinylsuccinate. According to the technical scheme, succinic acid and methyl alcohol react under the nitrogen protection condition to generate dimethyl succinate, the dimethyl succinate serves as a reaction solvent, sodium methoxide is dropwise added into the reaction solvent underthe ultrasonic oscillation condition, after dropwise adding is completed, a reflux reaction continues to be conducted for a period of time, and the reaction sufficiency can be improved through microcosmic vibration of fluid; after the reaction is finished, stirring, slurrying and suction filtration are performed, washing with absolute methanol is performed, and fractionation is performed so as torecover methanol and dimethyl succinate; the filter cake is neutralized with dilute sulfuric acid, and reduced pressure distillation is performed to obtain a final product. On the basis, a pickling solution is prepared from a residual solution obtained by reduced pressure distillation, and calcium chloride is added into the excessive pickling solution, so that a calcium sulfate byproduct can be obtained; meanwhile, the high-temperature residual liquid after fractionation is used for heating the dimethyl succinate in the next stage, so that the waste heat is effectively utilized, and the sewagedischarge amount is reduced.
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Paragraph 0018-0020; 0023-0025
(2021/04/03)
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- Activator-free reactions of carboxylic ortho esters with cyclic β-diketones
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The reaction mechanisms of cyclic 1,3-diketones with trialkyl orthoformates and trimethyl orthoacetate in the absence of activators were theoretically and experimentally studied. The reactions proceed via C-C-coupling of the ionized forms of the reactants giving dialkyl acetals, which further transform into vinyl ethers. The reactions of the latter with ortho esters afford aldehydes (ketones). Related 2-acetylcyclopentanone reacts with trimethyl orthoacetate under argon to form a mixture of methyl enol ethers, whereas in the presence of air oxygen dimethyl glutarate is formed.
- Balaneva,Shestak,Novikov,Glazunov
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p. 1584 - 1598
(2021/09/08)
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- Metal-free reduction of unsaturated carbonyls, quinones, and pyridinium salts with tetrahydroxydiboron/water
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A series of unsaturated carbonyls, quinones, and pyridinium salts have been effectively reduced to the corresponding saturated carbonyls, dihydroxybenzenes, and hydropyridines in moderate to high yields with tetrahydroxydiboron/water as a mild, convenient, and metal-free reduction system. Deuterium-labeling experiments have revealed this protocol to be an exclusive transfer hydrogenation process from water. This journal is
- Li, Tiejun,Peng, Henian,Tang, Wenjun,Tian, Duanshuai,Xu, Guangqing,Yang, He
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p. 4327 - 4337
(2021/05/31)
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- Efficient Catalysts for the Green Synthesis of Adipic Acid from Biomass
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Green synthesis of adipic acid from renewable biomass is a very attractive goal of sustainable chemistry. Herein, we report efficient catalysts for a two-step transformation of cellulose-derived glucose into adipic acid via glucaric acid. Carbon nanotube-supported platinum nanoparticles are found to work efficiently for the oxidation of glucose to glucaric acid. An activated carbon-supported bifunctional catalyst composed of rhenium oxide and palladium is discovered to be powerful for the removal of four hydroxyl groups in glucaric acid, affording adipic acid with a 99 % yield. Rhenium oxide functions for the deoxygenation but is less efficient for four hydroxyl group removal. The co-presence of palladium not only catalyzes the hydrogenation of olefin intermediates but also synergistically facilitates the deoxygenation. This work presents a green route for adipic acid synthesis and offers a bifunctional-catalysis strategy for efficient deoxygenation.
- Deng, Weiping,Yan, Longfei,Wang, Binju,Zhang, Qihui,Song, Haiyan,Wang, Shanshan,Zhang, Qinghong,Wang, Ye
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supporting information
p. 4712 - 4719
(2021/01/20)
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- Manganese-catalyzed homogeneous hydrogenation of ketones and conjugate reduction of α,β-unsaturated carboxylic acid derivatives: A chemoselective, robust, and phosphine-free in situ-protocol
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We communicate a user-friendly and glove-box-free catalytic protocol for the manganese-catalyzed hydrogenation of ketones and conjugated C[dbnd]C[sbnd]bonds of esters and nitriles. The respective catalyst is readily assembled in situ from the privileged [Mn(CO)5Br] precursor and cheap 2-picolylamine. The catalytic transformations were performed in the presence of t-BuOK whereby the corresponding hydrogenation products were obtained in good to excellent yields. The described system offers a brisk and atom-efficient access to both secondary alcohols and saturated esters avoiding the use of oxygen-sensitive and expensive phosphine-based ligands.
- Topf, Christoph,Vielhaber, Thomas
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- Reduction of Activated Alkenes by PIII/PV Redox Cycling Catalysis
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The carbon–carbon double bond of unsaturated carbonyl compounds was readily reduced by using a phosphetane oxide catalyst in the presence of a simple organosilane as the terminal reductant and water as the hydrogen source. Quantitative hydrogenation was observed when 1.0 mol % of a methyl-substituted phosphetane oxide was employed as the catalyst. The procedure is highly selective towards activated double bonds, tolerating a variety of functional groups that are usually prone to reduction. In total, 25 alkenes and two alkynes were hydrogenated to the corresponding alkanes in excellent yields of up to 99 %. Notably, less active poly(methylhydrosiloxane) could also be utilized as the terminal reductant. Mechanistic investigations revealed the phosphane as the catalyst resting state and a protonation/deprotonation sequence as the crucial step in the catalytic cycle.
- Longwitz, Lars,Werner, Thomas
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supporting information
p. 2760 - 2763
(2020/02/05)
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- Ni-catalyzed direct alcoholysis of N-acylpyrrole-type tertiary amides under mild conditions
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N-Acylpyrrole-type amides are a class of versatile building blocks in asymmetric synthesis. We report that by employing Ni(COD)2/2,2′-bipyridine (5 mol%) catalytic system, the direct, catalytic alcoholysis of N-acylpyrrole-type aromatic and aliphatic amides with both primary and secondary alcohols can be achieved efficiently under very mild conditions (rt, 1 h) even at gram scale. By increasing the catalyst loading to 10 mol%, prolonging reaction time (18 h), and/or elevating reaction temperature to 50 °C/80 °C, the reaction could be extended to both complex and hindered N-acylpyrroles as well as to N-acylpyrazoles, Nacylindoles, and to other (functionalized) primary and secondary alcohols. In all cases, only 1.5 equiv. of alcohol were used. The value of the method has been demonstrated by the racemization-free, catalytic alcoholysis of chiral amides yielded from other asymmetric methodologies.
- Chen, Hang,Chen, Dong-Huang,Huang, Pei-Qiang
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p. 370 - 376
(2020/03/03)
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- Transition Metal-Free Reduction of Activated Alkenes Using a Living Microorganism
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Microorganisms can be programmed to perform chemical synthesis via metabolic engineering. However, despite an increasing interest in the use of de novo metabolic pathways and designer whole-cells for small molecule synthesis, the inherent synthetic capabilities of native microorganisms remain underexplored. Herein, we report the use of unmodified E. coli BL21(DE3) cells for the reduction of keto-acrylic compounds and apply this whole-cell biotransformation to the synthesis of aminolevulinic acid from a lignin-derived feedstock. The reduction reaction is rapid, chemo-, and enantioselective, occurs under mild conditions (37 °C, aqueous media), and requires no toxic transition metals or external reductants. This study demonstrates the remarkable promiscuity of central metabolism in bacterial cells and how these processes can be leveraged for synthetic chemistry without the need for genetic manipulation.
- Brewster, Richard C.,Suitor, Jack T.,Bennett, Adam W.,Wallace, Stephen
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supporting information
p. 12409 - 12414
(2019/08/16)
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- Preparation method of high-purity dimethyl succinyl succinate
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The invention provides a preparation method of high-purity dimethyl succinyl succinate.According to the technical scheme, a novel design is carried out on the synthesis condition of dimethyl succinylsuccinate; specifically, the preparation method of thehigh-purity dimethyl succinyl succinate comprises the following steps of: firstly, reacting succinic acid and methanol under the condition of nitrogen protection to generate dimethyl succinate, taking the dimethyl succinate as a reaction solvent, dropwise adding sodium methoxide into the dimethyl succinate under the condition of ultrasonic oscillation, continuously carrying out reflux reaction for a period of time after the dropwise addition is finished, and improving the adequacy of the reaction by micro-vibration of a fluid;stirring and pulping are carried outafter the reaction is finished, suction filtration is carried out, anhydrous methanol is used for washing, and fractional distillation is carried out, so that the methanol and the dimethyl succinate are recovered;afilter cake is subjected to reduced pressure distillation after being neutralized by dilute sulfuric acid to obtain a final product.The preparation method of thehigh-purity dimethyl succinyl succinate can effectively ensure the yield of the product, simplify the process steps to a certain extent, and simultaneously obtain the product with higher purity.The preparation method of thehigh-purity dimethyl succinyl succinate achieves good technical effect by innovative technical improvement and has great popularization prospect.
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Paragraph 0018-0020; 0023-0025
(2019/06/30)
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- Hydrogenation of Ketones and Esters Catalyzed by Pd/C?SiO2
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Hydrogenation of unsaturated ketones and esters with molecular hydrogen on the 5%Pd/C?SiO2 heterogeneous catalyst has been studied. The reaction direction and yield are determined by the starting compounds structure. Hydrogenation of unsaturated ketones containing phenyl group at the double carbon–carbon atom is accompanied by the reduction of the ketone group into the alcohol one. Hydrogenation of unsaturated esters is accompanied by transesterification.
- Akchurin,Baibulatov,Dokichev
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p. 195 - 198
(2018/03/26)
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- Sulfonic acid-functionalized organic knitted porous polyaromatic microspheres as heterogeneous catalysts for biodiesel production
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The use of renewable energy sources decreases the consequences of greenhouse gas emission from fossil fuels. Biodiesel, an easily burning and biodegradable fuel, is an alternative to conventional diesel fuel. The esterification of long-chain fatty acids and transesterification of triglycerides are two major reactions widely used to convert vegetable oils or animal fats into biodiesel. As solid acid catalysts are considered promising candidates for biodiesel production, we have synthesized a series of organic knitted porous polyaromatics (OPPs) using pyrene, anthracene, and naphthalene as monomers via Friedel-Crafts alkylation, followed by crosslinking reactions. The resultant polymers showed good surface morphology, stability and swelling property, high capacity for functionalization due to the unreacted bromomethyl groups on the surface, and excellent hydrophobicity. The sulfonated polymer microspheres obtained by the surface sulfonation showed good surface acidity; thus, they can be employed as heterogeneous solid acid catalysts for the esterification of long-chain fatty acids and transesterification of triglycerides, and they are reusable without any leaching of functional groups.
- Varyambath, Anuraj,Kim, Mi-Ra,Kim, Il
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p. 12745 - 12753
(2018/08/04)
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- Method for preparing disuccinate
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The invention relates to a method for preparing disuccinate. The method comprises the step of subjecting glucose, fructose, cellobiose and microcrystalline cellulose, which serve as raw materials, toa catalyzed selective oxidation process in a manner of taking molecular oxygen as an oxygen supply, thereby obtaining the disuccinate. According to the method, the raw materials employed can be obtained from biomass resources such as starch, cellulose and wastes of agriculture and forestry, the catalyst composition is simple, the reaction conditions are mild, and the selectivity of the target product disuccinate is high, so that the method has an important application prospect.
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Paragraph 0011-0016; 0018; 0026
(2019/01/07)
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- BIOFUELS PRODUCTION FROM BIO-DERIVED CARBOXYLIC-ACID ESTERS
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A process for producing biofuels compounds directly from carboxylic acid esters recovered from a fermentation system is described. The process involves taking a fermentation broth that has been reduced to a dry powder containing free organic acids; reacting the carboxylic acid in the powder with an alcohol solvent under a CO2-containing atmosphere in substantial absence of any other acid catalyst at a reaction temperature and pressure that corresponds to supercritical, critical or near critical conditions for at least one of the alcohol or CO2 to synthesize an ester, then subjecting the ester to either hydrogenolysis or hydrogenation to form a biofuel.
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Paragraph 0053; 0055
(2017/04/11)
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- Hydrogen Gas-Mediated Deoxydehydration/Hydrogenation of Sugar Acids: Catalytic Conversion of Glucarates to Adipates
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The development of a system for the operationally simple, scalable conversion of polyhydroxylated biomass into industrially relevant feedstock chemicals is described. This system includes a bimetallic Pd/Re catalyst in combination with hydrogen gas as a terminal reductant and enables the high-yielding reduction of sugar acids. This procedure has been applied to the synthesis of adipate esters, precursors for the production of Nylon-6,6, in excellent yield from biomass-derived sources.
- Larson, Reed T.,Samant, Andrew,Chen, Jianbin,Lee, Woojin,Bohn, Martin A.,Ohlmann, Dominik M.,Zuend, Stephan J.,Toste, F. Dean
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supporting information
p. 14001 - 14004
(2017/10/17)
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- Palladium–Bis(carbene) Catalysts for the Bisalkoxycarbonylation of Olefins to Succinic Diesters
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A series of Pd-bis(NHC) (NHC = N-heterocyclic carbene) complexes possessing various anions and substituents were used in the bisalkoxycarbonylation of olefins (α-olefins and ethylene) to afford industrially useful succinic diesters in modest to good yields. The influence of different ligands and counteranions of the Pd complexes on their catalytic activity was assessed, and it was found that dimeric Pd–bis(NHC)Br was the best catalyst for the bisalkoxycarbonylation reactions. The structure of dimeric Pd–bis(NHC)Br was confirmed by X-ray crystallographic analysis.
- Cho, Yu Jin,Lim, Yu Na,Yoon, Woojin,Yun, Hoseop,Jang, Hye-Young
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supporting information
p. 1139 - 1142
(2017/03/08)
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- Method for synthesizing carboxylic methyl ether by reaction between acid anhydrides and dimethyl carbonate
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The invention discloses a method for synthesizing carboxylic methyl ether by a reaction between acid anhydrides and dimethyl carbonate. The method is characterized by comprising the following steps: taking raw materials acid anhydride, dimethyl carbonate and a catalyst, wherein molar ratio of acid anhydride to dimethyl carbonate is 1:1-1:100, the catalyst accounts for 1-20 wt% of mass of acid anhydride, acid anhydride is aliphatic acid anhydride or aromatic acid anhydride, and the catalyst is Lewis acid or protonic acid; adding acid anhydride, dimethyl carbonate and the catalyst into a high-pressure reaction vessel, reacting at 80-350 DEG C for 1-8h, cooling to room temperature, discharging gas, and fetching a material obtained after the reaction; pouring the material into a saturated sodium bicarbonate aqueous solution, extracting with ethyl acetate or dichloromethane, merging extract liquor, drying, filtering, and distilling a filtrate to remove a solvent. The remaining product is prepared carboxylic methyl ether. By the method, no additional organic solvent is required. The method is green and environment-friendly, is simple to operate, has short reaction time, has high acid anhydride conversion rate, and has a good application prospect.
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Paragraph 0015
(2017/08/28)
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- A carbonyl synthesis method of succinic acid dimethyl ester
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The invention relates to a method for synthesizing dimethyl succinate and particularly relates to a method for synthesizing dimethyl succinate through carbonylation, belonging to the field of chemical preparation methods. The method comprises the following steps: synthesizing dimethyl succinate from methyl acrylate with a synthesis gas through carbonylation reaction, wherein a rhodium-phosphine complex is a primary catalyst, and p-toluenesulfonic acid is a catalytic promoter; and in a catalytic system, n(Rh):n(P) is 1: 10 to 1:30, and n(Rh):(PTSA) is 1:4 to 1:10. The catalyst adopted by the method disclosed by the invention is good in stability, activity and selectivity. The synthesis condition for dimethyl succinate is relatively gentle, and the corrosion on equipment is low. The conversation rate of methyl acrylate is not lower than 80%, and the selectivity to dimethyl succinate is not lower than 80%.
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Paragraph 0018; 0020
(2017/10/28)
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- Valuable new platform chemicals obtained by valorisation of a model succinic acid and bio-succinic acid with an ionic liquid and high-pressure carbon dioxide
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The potential application of biomass and catalysts is crucial to form a bridge between the emerging bio-based industry and the current process technology. Using this approach to succinic acid, a biomass derived acid, might lead to new routes for derivative production, opening its transition to the industrial scale. A considerable number of succinic acid-based products were obtained in this work in advanced, one-pot processes executed in a green solvent, supercritical carbon dioxide. Ionic liquids, which present an alternative to volatile and flammable solvents, allowed for a subsequent transformation of carbohydrate rich renewable feedstock by a simple reaction in alternative media. Reactions give a possibility of conversion of a cheap lignocellulosic biomass to succinic acid-based products, such as ethanol having a potential application in biorefinery, as well as to pyrrolidine-2,5-diones, representing antibiotics and to succinic acid esters, valuable platform chemicals. Mechanistic analysis of the formation of reaction products was successfully developed. The valorisation of a model succinic acid was compared with the valorisation of a bioderived succinic acid under identical reaction conditions and the results are discussed. The palladium catalyst nanoparticles formed seem to be stabilised by ionic liquids allowing for five successive cycles with efficient conversion and selectivity in the hydrogenation of bio-succinic acid. The presented valorisation of a biomass derived carboxylic acid is an excellent starting point for derivative production.
- Silva, Daniel,Bogel-Lukasik, Ewa
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p. 4048 - 4060
(2017/09/07)
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- Method of selectively catalytically oxidizing biomass-based furan compound
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The invention discloses a method of selectively catalytically oxidizing a biomass-based furan compound. The method comprises the following step of: by taking a heteropolyacid functional ionic liquid as a catalyst and an alcohol solution as a reaction medium, obtaining dicarboxylic acid or dicarboxylate in the conditions that the reaction temperature is 100-150 DEG C, the reaction time is 1-3h and the oxygen pressure is 0.5-1.0MPa, wherein over 62.35% of difumarate selectivity is obtained. The single chemical yield and selectivity for oxidizing preparation of a biomass-based furan derivative are far higher than those of the prior art. The method has the remarkable advantage that an ionic liquid catalyst can be recovered and recycled by simply adjusting the temperature. The method disclosed by the invention is mild in reaction condition, green and safe in process and simple to operate, and can realize intermittent and continuous production.
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Paragraph 0110-0113
(2017/07/19)
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- DEOXYDEHYDRATION OF SUGAR DERIVATIVES
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The disclosure provides methods for deoxydehydration of sugar-based derivatives using hydrogen gas as a reducing agent.
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Page/Page column 0134; 0135; 0136;
(2017/09/09)
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- Two "classical" Old Yellow Enzymes from Chryseobacterium sp. CA49: Broad substrate specificity of Chr-OYE1 and limited activity of Chr-OYE2
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Two putative Old Yellow Enzyme (OYE) homologues, Chr-OYE1 and Chr-OYE2, were identified from the genome of Chryseobacterium sp. CA49 as new members of the "classical" subfamily. Chr-OYE1 and Chr-OYE2 were most closely related to the SYE4 from Shewanella oneidensis and NerA from Agrobacterium radiobacter with 41% and 45% identity, respectively. Both enzymes were expressed in Escherichia coli in soluble form, but their catalytic abilities as ene-reductases were quite different. Among the 19 substrate tested, Chr-OYE1 could catalyze the reduction of 18 of them including an ynone with excellent stereoselectivity for several prochiral ones, and its specific activity was roughly 1100-fold high than Chr-OYE2, which only catalyzed 3 of the substrates. After restoring the conserved tyrosine, Chr-OYE2 remained the same substrate spectrum, but showed significantly enhanced activity and stereoselectivity.
- Pei, Xiao-Qiong,Xu, Meng-Yu,Wu, Zhong-Liu
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- Dimethyl succinate preparation method
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The present invention discloses a dimethyl succinate preparation method, which comprises that succinic acid and methanol are poured into a reaction kettle at a proportion, heating is performed, the water generated from the reaction, a water-carrying agent and the methanol circulate in the system along with the temperature increase, the water and the methanol obtained during the circulating process are separated, the separated methanol refluxes to the reaction kettle so as to continuously react, and the separated water is directly discharged into a wastewater treatment system. According to the present invention, the method has characteristics of production cycle shortening, production cost saving, product quality improving and avoidance of emission of a lot of three-waste; and the cleaning dimethyl succinate production can be achieved, and the method is the dimethyl succinate production method suitable for different scales of industrial productions.
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Paragraph 0017; 0018; 0019; 0020; 0021
(2016/10/07)
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- PROCESS FOR THE PREPARATION AND ISOLATION OF CARBOXYLIC ESTERS
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The disclosed methods for preparing and isolating carboxylic esters ensure a high product purity and minimize technical complexity. These methods are based on the reaction of a carboxylic acid with an alcohol in an aqueous medium. In some examples, the alcohol is used both for the esterification and for the precipitation of the salts, preferably ammonium salts, formed in the synthesis.
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Paragraph 0074-0081
(2016/11/14)
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- A PROCESS FOR PREPARING SUCCINATE ESTER
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This invention relates to a process for preparing succinate ester from a succinic acid salt present in a fermentation broth. In the first stage of this invention, renewable carbon resources are utilized to produce succinic acid in the form of a succinic acid salt through biological fermentation. The succinic acid salt present in the fermentation broth is subjected to double displacement reaction with a strong acid leading to the release of succinic acid. Succinic acid is recovered by fractional crystallization integrated with an alcohol washing step and subjected to esterification reaction to produce succinate ester which is purified by fractional distillation. The succinate ester thus obtained is converted into 1,4-butanediol, gamma-butyrolactone and tetrahydrofuran through hydrogenation reactions. The succinate ester can also be hydrolyzed to yield highly pure succinic acid.
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Paragraph 0098
(2016/11/07)
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- A levulinic acid and levulinate catalytic oxidation process for the conversion of
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The invention relates to a method for catalytic oxidation conversion of levulinic acid and levulinic acid ester. The method adopts air or oxygen as the oxidant, and a bivalent manganese compound and nitric acid, nitrate or nitrous acid, nitrite are employed as a composite catalyst to catalyze levulinic acid or levulinic acid ester liquid phase selective oxidation and esterification reaction under mild conditions, thus obtaining succinic acid diester. The method has the characteristics of high catalytic oxidation efficiency and mild reaction condition, the bivalent manganese compound and nitric acid, nitrate or nitrous acid, nitrite involved in the composite catalyst are cheap and easily available, and the product is easy to separate and purify, so that the method has very good practicability and broad application prospects.
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Paragraph 0024
(2017/03/08)
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- Cross-Metathesis of Bronsted Acid Masked Alkenylamines with Acrylates for the Synthesis of Polyamide Monomers
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Ruthenium-alkylidene-catalyzed cross-metathesis of a range of homologous alkenylamine salts provides expedient and high-yielding routes to commercially valuable polyamide monomers using a single catalyst, telescopic workup, and mild experimental conditions.
- Spiccia, Nicolas Daniel,Solyom, Szabolcs,Woodward, Clint Peter,Jackson, William Roy,Robinson, Andrea Jane
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p. 1798 - 1805
(2016/03/15)
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- Acid-catalyzed oxidation of levulinate derivatives to succinates under mild conditions
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Levulinate derivatives are an attractive platform for the production of renewable chemicals. Here we report on the oxidation of methyl levulinate into dimethyl succinate with peroxides under mild conditions using Br?nsted and Lewis acid catalysts. Selectivities to succinate and acetate derivatives of approximately 60 and 40 %, respectively, were obtained with strong Br?nsted acids in methanol. Although the molecular structure (i.e., carbon-chain length and branching around the C=O group) and the oxidant type affect the product distribution, solvent choice has the strongest impact on changing the location of oxygen insertion into the carbon backbone. Specifically, switching the solvent from methanol to heptane resulted in a decrease in the succinate/acetate ratio from 1.6 to 0.3. In contrast to Br?nsted acids, we demonstrate that the nature of the metal cation is responsible for changing the reaction selectivity of water-tolerant Lewis acidic triflate salts.
- Wang, Yuran,Vogelgsang, Ferdinand,Román-Leshkov, Yuriy
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p. 916 - 920
(2015/03/18)
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- PROCESS FOR THE PREPARATION OF SUCCINIC ACID ESTER
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A process for the production of dialkyl succinate from a bio-succinic acid feedstock comprising the steps of; (a) feeding solid bio-succinic acid to a first reactor where it is contacted with alkanol, said first reactor being operated at a suitable temperature and pressure to enable autocatalytic esterification to occur; (b) passing a stream removed from the first reactor comprising unreacted succinic acid, mono alkyl ester, dialkyl ester, alkanol, water and impurities to a point at or near the top of a reaction zone columm operated at temperatures and pressures to enable esterification of the succinic acid and further esterification of the mono alkyl ester, and passing said stream in counter-current reaction to upflowing additional alkanol; (c) removing a stream from at or near the bottom of the reaction zone column comprising components selected from residua! succinic acid, mono alkyl ester, dialkyl ester, impurities and alkanol and passing said stream to a bottoms stream separation zone where said di-alkyl ester is separated from alkanol, and from the succinic acid, mono alkyl ester and impurities; (d) recycling the succinic acid and mono alkyl ester to the reaction zone column; (e) removing at least some of the impurities as a purge; and (f) removing a stream comprising alkanol, water and organic components from at or near the top of the reaction zone column and passing said stream to a top stream distillation zone where the alkanol is separated, from the water and from the organic components and recycling the organic components to the reaction zone column.
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Page/Page column 32-35
(2015/06/18)
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- PROCESS FOR THE PREPARATION OF SUCCINIC ACID ESTER
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A process for the production of dialkyl succinate from a bio-succinic acid feedstock comprising the steps of: feeding bio-succinic acid to a point at or near the bottom of a reaction distillation zone column operated at temperatures and pressures to enable esterification of the succinic acid and passing said stream co-currently with upflowing alkanol such that said esterification reaction occurs: removing an overhead vapour stream from at or near the top of the reaction distillation zone column comprising di-ester, alkanol, water of esterification and organic components and passing said stream to an alkanol separation column where the alkanol is separated from the water of esterification and from the organic components; removing a side draw from the alkanol separation column from a point below the feed point thereto, said side draw comprising partially immiscible organic and aqueous phases; passing said side draw to phase separation apparatus where the partially immiscible organic and aqueous phases are separated; passing said organic phase to a column where the dialkyl succinate is separated from residual water and other organic components; and recovering the dialkyl succinate.
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Page/Page column 25-29
(2015/06/18)
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- Process for treating homoserin compounds
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The present invention relates to the preparation of a useful compound which can be used as an intermediate product for preparing an important compound in the industrial field from a homoserine-based compound and provides a process for treating a homoserine-based compound, capable of simply mass producing a useful compound from a homoserine-based compound with excellent efficiency.(AA) Homoserine-based compound(BB) Product(CC) GBL derivative(DD) Halo-GBL(EE, FF, GG) GBL puranone(HH) Puranone(II) Dialkyl succinate(JJ) Step 1(KK) Step 2(LL) Step 3(MM) Step 4(NN) Step 5(OO) Step 6(PP) Step 7COPYRIGHT KIPO 2016
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Paragraph 0300-0303
(2017/01/02)
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- BIOFUELS PRODUCTION FROM BIO-DERIVED CARBOXYLIC-ACID ESTERS
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A process for producing for producing biofuels compounds directly from carboxylic acid esters recovered from a fermentation system is described. The process involves taking a fermentation broth that has been reduced to a dry powder containing free organic acids; reacting the carboxylic acid in the powder with an alcohol solvent under a CO2-containing atmosphere in substantial absence of any other acid catalyst at a reaction temperature and pressure that corresponds to supercritical, critical or near critical conditions for at least one of the alcohol or CO2 to synthesize an ester, then subjecting the ester to either hydrogenolysis or hydrogenation to form a biofuel.
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- PROCESS FOR THE PREPARATION OF DIALKYL SUCCINATE FROM MALEIC ANHYDRIDE
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A process for the production of dialkyl succinate from a feedstock comprising maleic anhydride, said process comprising the steps of providing the feed in the liquid phase to a reactor operated at a temperature of at least about 150°C; contacting said feed with hydrogen at a pressure of at least about 300 psig in the presence of an acid tolerant catalyst and an alkanol wherein at least some of the carbon carbon double bonds of the maleic anhydride are hydrogenated to form succinic acid and that the heat generated promotes esterification to dialkyl succinate acid in situ; and recovering a stream comprising dialkyl succinate from the reactor.
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Page/Page column 11; 12
(2015/05/05)
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- Heterologous expression and characterization of the ene-reductases from Deinococcus radiodurans and Ralstonia metallidurans
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The Old Yellow Enzyme (OYE) homologues or ene-reductases (ER) from Deinococcus radiodurans (DrER) and Ralstonia metallidurans (RmER) were cloned and characterized. Sequence and phylogenetic analysis revealed both these enzymes to belong to the YqjM-like or "thermophilic-like" group of OYEs, both sharing more than 60% sequence similarity to the ER from Thermus scotoductus. This group of OYEs is characterized by a conserved cysteine residue modulating the redox potential of the flavin cofactor as well as a conserved tyrosine residue located at the N-terminus region involved in binding certain ligands. The genes were recombinantly expressed in Escherichia coli as functional soluble proteins. Both ERs have monomer molecular weights of approximately 40 kDa, with DrER a homodimer in solution and RmER a monomer. DrER and RmER are optimally active at pH 7-7.5 at 30 C and 35 C respectively. Although the enzymes showed comparable affinities towards the ubiquitous ER substrate 2-cyclohexenone, the specific activity and catalytic efficiency of DrER were more than twice those observed for RmER. Similar to other members of this subclass of ERs, no conversion was detected with cyclic Cβ substituted enones, and only DrER was able to convert citral. Both DrER and RmER were highly active at reducing N-phenyl substituted maleimides. The selectivity of the ERs was assessed using both the isomers of carvone, which were converted with high diastereomeric excesses. Ketoisophorone and 2-methylcyclopentenone were converted to their (R)- and (S)-enantiomeric products respectively. Finally, a light-driven cofactor regeneration system was used to drive enzymatic reduction in the absence of NAD(P)H.
- Litthauer,Gargiulo,Van Heerden,Hollmann,Opperman
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- PROCESS FOR PRODUCING 1,4- BUTANEDIOL BY HYDROGENATING DIALKYL MALEATE IN MIXED LIQUID/VAPOR PHASE
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A process for the production of 1,4-butanediol and tetrahydrofuran by catalytic hydrogenation of dialkyl maleates includes the following steps: a) hydrogenating a stream of dialkyl maleate in a first stage of reaction over suitable catalysts to produce dialkyl succinate;b) further hydrogenating the dialkyl succinate in a second stage of reaction, by using a different suitable catalyst, for producing mainly 1,4-butanediol, together with gamma-butyrolactone and tetrahydrofuran as co-products. In both stages of reaction the conditions, as hydrogen/organic feed ratio, pressure and temperature, are such to maintain the reactors in mixed liquid/vapor phase.
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Paragraph 0105-0109
(2014/10/29)
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- Efficient microwave-assisted esterification reaction employing methanesulfonic acid supported on alumina as catalyst
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A rapid and efficient protocol assisted by microwave irradiation for the synthesis of esters using methanesulfonic acid (CH3SO3H) supported on Al2O3 (AMA) as catalyst and free of solvent is described. The products were obtained in good yields and purity, with reduced reaction time, and the process is simple and environmentally benign. Copyright
- Fabian, Lucas,Gomez, Matias,Kuran, Juan A. Caturelli,Moltrasio, Graciela,Moglioni, Albertina
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p. 2386 - 2392
(2014/07/22)
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