- Effect of boron content on 1,4-butanediol production by hydrogenation of succinic acid over Re-Ru/BMC (boron-modified mesoporous carbon) catalysts
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A series of Re-Ru bimetallic catalysts supported on mesoporous boron-modified carbon (denoted as Re-Ru/xBMC, x?=?B/C molar ratio) were prepared by a single-step surfactant-templating method and a subsequent incipient wetness impregnation method, and they were used for liquid-phase hydrogenation of succinic acid to 1,4-butandiol (BDO). The effect of boron addition on the catalytic activities and physicochemical properties of Re-Ru/xBMC catalysts was investigated. It was found that the addition of boron into carbon support affected surface area, metal dispersion, and reducibility of rhenium and ruthenium species in the Re-Ru/xBMC catalysts. It was also observed that boron species in carbon framework existed in several different phases such as substituted boron, partial oxidized boron, and boron oxide. In particular, the amount of substituted boron species was closely related to the hydrogen adsorption behavior of Re-Ru/xBMC catalysts. The amount of weak hydrogen-binding sites increased with increasing the amount of substituted boron species of the catalysts. Yield for BDO in the hydrogenation of succinic acid showed a volcano-shaped trend with respect to B/C molar ratio. This result was in good agreement with the amount of weak hydrogen-binding sites of the catalysts. It was revealed that TOFBDO increased with increasing the amount of weak hydrogen-binding sites of Re-Ru/xBMC catalysts. Among the catalysts, Re-Ru/0.04BMC with the largest amount of weak hydrogen-binding sites served as an efficient catalyst in the selective formation of BDO by hydrogenation of succinic acid.
- Kang, Ki Hyuk,Han, Seung Ju,Lee, Jong Won,Kim, Tae Hyeop,Song, In Kyu
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- Hydrogenation of γ-Butyrolactone to 1,4-Butanediol over CuCo/TiO2 Bimetallic Catalysts
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Titania-supported monometallic and bimetallic Cu-Co catalysts were prepared using (co)impregnation and studied for the hydrogenation of γ-butyrolactone (GBL) to 1,4-butanediol (BDO) at temperatures from 100 to 180 °C and a hydrogen pressure of 3.4 MPa. The highest catalytic activity occurred at a Cu:Co atomic ratio of 1:9 (Cu0.1Co0.9/TiO2), and a 95% yield of BDO was obtained. Characterization results showed mainly small nanoparticles (average size 2.6 nm) for pure Cu/TiO2, large particles (~19.8 nm) for pure Co/TiO2, and a bimodal particle size distribution of both small (~2.3 nm) and large (~16.5 nm) particles for the bimetallic catalyst with a Cu:Co ratio of 1:1. The addition of ~10 mol % Cu to Co/TiO2 increased the reducibility of the Co and resulted in the formation of core-shell CuCo bimetallic nanoparticles with a Co-rich core and Cu-rich shell. GBL hydrogenation in liquid ethanol and water produced an ester (ethyl 4-hydroxybutanoate) and a carboxylic acid (4-hydroxybutanoic acid) as the major products, respectively. GBL hydrogenation in 1,4-dioxane likely went through a 2-hydroxytetrahydrofuran (2-HTHF) intermediate. The 2-HTHF underwent facile ring-opening tautomerization to 4-hydroxybutanal (4-HB), followed by rapid hydrogenation to BDO at a reaction rate up to 700 times faster than GBL hydrogenation. The Cu0.1Co0.9/TiO2 catalyst maintained the BDO selectivity and about 80% of initial activity for GBL hydrogenation after 150 h time on stream in a continuous flow reactor.
- Huang, Zhiwei,Barnett, Kevin J.,Chada, Joseph P.,Brentzel, Zachary J.,Xu, Zhuoran,Dumesic, James A.,Huber, George W.
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- Extremely facile and selective nickel-catalyzed allyl ether cleavage
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Child's play! Allyl ethers as protecting groups for hydroxyl functions can be removed readily with a combination of DIBAL and catalytic amounts of [NiCl2(dppp)]. Propene is expelled in this remarkably selective reaction, and a nickel-catalyzed hydroalumination-elimination pathway is proposed. dppp = propane-1,3-diylbis(diphenylphosphane).
- Taniguchi, Takahiko,Ogasawara, Kunio
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- Thermodynamic equilibria between polyalcohols and cyclic ethers in high-temperature liquid water
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Thermodynamic equilibrium constants between polyalcohols and cyclic ethers in water at 573 K were determined by measuring their concentrations after the long-term reaction in a batch reactor. Intramolecular dehydration reactions of polyalcohols were important for conversion of biomass-derived carbohydrates; however, the yields of products were limited by thermodynamic equilibria between polyalcohols and products. All the thermodynamic equilibrium constants were estimated by the long-term dehydration reaction of 1 mol ·dm-3 polyalcohol aqueous solutions at 573 K. The thermodynamic equilibrium constants between butanepolyols or pentanepolyols and five-membered or six-membered cyclic ethers were within a range from (39 to 337) mol ·dm-3.
- Yamaguchi, Aritomo,Hiyoshi, Norihito,Sato, Osamu,Bando, Kyoko K.,Masuda, Yoshio,Shirai, Masayuki
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- A temperature-controlled reversible ionic liquid - Water two phase - Single phase protocol for hydrogenation catalysis
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An ionic liquid - water system that undergoes a reversible two phase - single phase transformation dependent upon temperature has been used as a novel medium for the transition-metal-catalyzed hydrogenation of a water soluble substrate. At room temperature, the ionic liquid 1-octyl-3-methylimidizolium tetrafluoroborate, containing [Rh(η4-C7H8)(PPh3) 2][BF4] catalyst, forms a separate layer to water containing 2-butyne-1,4-diol. In a stirred autoclave the mixture was pressurized with hydrogen to 60 atm (1 atm = 101.325 kPa) and heated to 80°C giving a homogeneous single phase solution. On cooling to room temperature, two phases reform, with the ionic liquid phase containing the catalyst and the aqueous phase containing a mixture of 2-butene-1,4-diol and butane-1,4-diol products that can be simply removed without catalyst contamination.
- Dyson,Ellis,Welton
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- Comparison of Carbon-13 Nuclear Magnetic Resonance Methods for the Analysis of Multiple Partially Deuteriated Products from Catalytic Reactions: Heptan-1-ol and 2-Methylpropanol
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Products from the hydrocarbonylation of hex-1-ene or prop-2-en-1-ol using H2-CO or D2-CO in EtOH or EtOD have been analysed using 13C NMR techniques.Where there are up to four isotopomers in the products, analysis of β-shifted resonances in the 13C- NMR spectrum can give enough information for quantification of all isotopomers.Using prop-2-en-1-ol, D2-CO and EtOH, the 2-methylpropanol produced is a mixture of 16 different isotopomers.These can be individually quantified by analysis of the 13C- NMR spectrum.In particular, the resonance from the methyl C atom shows β and γ shifts, the latter being different for different types of γ-D atom.These analytical methods are shown to be superior to other possibilities including 1H NMR and mass spectrometry.
- MacDougall, Joanna K.,Simpson, Michael C.,Cole-Hamilton, David J.
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- High chemo and regioselective formation of alcohols from the hydrocarbonylation of alkenes using cooperative ligand effects
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The hydrocarbonylation of alkenes, including allyl alcohol, catalysed by rhodium complexes and wide angle bidentate ligands together with PEt 3, gives alcohols as the primary products with high chemo and regio-selectivity.
- Boogaerts, Ine T.I. F.,White, Daniel F. S.,Cole-Hamilton, David J.
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- Continuous hydrogenation of 2-butyne-1,4-diol to 2-butene- and butane-1,4-diols
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Continuous catalytic hydrogenation of 2-butyne-1,4-diol (B3D) was carried out in a fixed-bed reactor over 1% Pt/CaCO3 catalyst to give 2-butene-1,4-diol (B2D) and butane-1,4-diol (B1D) without formation of any other side products. In case of continuous hydrogenation, higher selectivity (66%) to B2D could be obtained and the selectivity pattern was completely different from that found in case of batch slurry operation in which B1D selectivity was very much higher (83%) than the B2D selectivity (17%). Another interesting feature was that by varying the contact time, the selectivity to both B2D as well as B1D could be varied over a wide range which is an attractive option to obtain the desired products mix of B1D and B2D, depending on the fluctuation in the market demand. Further, a mathematical model for reactor performance was also developed on the basis of the kinetic data obtained previously in a batch slurry reactor. The predicted values of conversion, selectivity, and rate of hydrogenation were found to agree with the experimental data over a wide range of conditions.
- Rode,Tayade,Nadgeri,Jaganathan,Chaudhari
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- A new carboxylesterase from Brevibacterium linens IFO 12171 responsible for the conversion of 1,4-butanediol diacrylate to 4-hydroxybutyl acrylate: Purification, characterization, gene cloning, and gene expression in Escherichia coli
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A carboxylesterase that is responsible for conversion of 1,4-butanediol diacrylate (BDA) to 4-hydroxybutyl acrylate (4HBA) was found in Brevibacterium lines IFO 12171, and purified to homogeneity. The purified enzyme was active toward a variety of diesters of ethylene glycol, 1,4-butanediol, and 1,6-hexanediol. The Km and kcat of the enzyme for BDA were 3.04 mM and 203,000 s-1, respectively. The reaction with the purified enzyme gave 98 mM 4HBA from 100 mM BDA for 60 min. The enzyme gene was cloned from the chromosomal DNA of the bacterium. The open reading frame encoding the enzyme was 1176 bp long, corresponding to a protein of 393 amino acid residues (molecular mass=42,569Da). The deduced amino acid sequence contained the tetra peptide motif sequence, STTK, and the serine residue was confirmed to be the catalytic center of BDA esterase by site-directed mutagenesis for several amino acid residues. The gene was expressed in Escherichia coli under the control of the lac promoter, and the gene product (a fusion protein with 6 amino acid residues from β-galactosidase) showed the same catalytic properties as the enzyme from the parent strain.
- Sakai, Yasuyoshi,Ishikawa, Junko,Fukasaka, Shunji,Yurimoto, Hiroya,Mitsui, Ryoji,Yanase, Hideshi,Kato, Nobuo
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- Effect of Ethers on Reactions of Butylcoppers with α,β-Unsaturated Ketones in Toluene
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Mixtures of butyllithium and copper iodide prepared in toluene react with α,β-unsaturated ketones predominantly in a 1,2-fashion. Addition of various ethers to the system results in some preference for the 1,4-product. The structural characteristics of ethers which influence 1,4-addition have been revealed. Reactions with chiral ethers did not alter the stereochemistry of the product. The results are correlated with the current views on the mechanism of organocuprate reactions.
- Kingsbury, Celia L.,Smith, Robin A. J.
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- A Novel and Unusual Reaction of Enol Ethers with Benzyltriethylammonium Borohydride and Chlorotrimethylsilane
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Benzyltriethylammonium borohydride-chlorotrimethylsilane reagent system has been found to effect a novel and unusual reaction with cyclic and acyclic enol ethers 1 to give exclusively diols and alcohols 2 respectively in high yields, under very mild reaction conditions.
- Baskaran, S.,Chidambaram, N.,Narasimhan, N.,Chandrasekaran, S.
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- A Schiff Base Modified Pd Catalyst for Selective Hydrogenation of 2-Butyne-1,4-diol to 2-Butene-1,4-diol
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Abstract: Schiff-base modified Pd nanoparticles (NPs) supported on silica with an average size of ca. 2?nm have been synthesized via a one-pot aldimine condensation followed by impregnation-reduction of a palladium precursor, and the sample exhibits an excellent catalytic activity and selectivity in hydrogenation of 2-butyne-1,4-diol (BYD) to 2-butene-1,4-diol (BED). Under the mild reaction conditions (50?°C, 2?MPa H2, and 4?h) and additive-free, 95.2% BYD conversion has been achieved with ca. 100% BED selectivity over the Pd/SiO2–Schiff catalyst, and the Pd/SiO2–Schiff catalyst presents an excellent catalytic stability. The above results are much better than that of commercial Lindlar catalyst, and the improved catalytic performance is attributed to the strong metal–support interaction derived from the coordination of nitrogen sites (Schiff-base) to Pd NPs, based on catalyst characterization results. Graphic Abstract: Featured by additive-free and high selectivity, hydrogenation of 2-butyne-1,4-diol to 2-butene-1,4-diol over the Pd/SiO2–Schiff catalyst has been developed, aiming for green production of fine chemicals.[Figure not available: see fulltext.]
- Li, Haomeng,Wang, Xinkui,Chen, Xiao,Li, Chuang,Wang, Min,Yi, Yanhui,Ji, Min,Wang, Huilong,Shao, Zhengfeng,Liang, Changhai
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- Bimetallic Synergy Effects of Phyllosilicate-Derived NiCu@SiO2 Catalysts for 1,4-Butynediol Direct Hydrogenation to 1,4-Butanediol
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Hydrogenation of 1,4-butynediol (BYD) to 1,4-butanediol (BDO) is a two-step process, with an initial hydrogenation of BYD to 1,4-butenediol (BED) and the subsequent hydrogenation of BED to BDO. However, the BYD hydrogenation also involves many side reactions originated from the isomerization of BED. In order to inhibit the isomerization pathways, phyllosilicate-derived bimetallic NiCu@SiO2 catalysts have been developed for efficient C≡C/C=C hydrogenation in this work. Due to the formation of phyllosilicate matrix and highly dispersed metal nanoparticles, NiCu@SiO2 showed total BYD conversion with extremely high BDO selectivity compared to a conventional impregnated Ni/SiO2 catalyst. A remarkable result of NiCu@SiO2 catalysts is that a new type of bimetallic catalytic sites responsible for the high hydrogenation activity can be differentiated from the Ni phyllosilicate matrix by the induction of Cu species, and these neighboring bimetallic sites with the help of weak acid phyllosilicate interface, can realize to stabilize the activated BED species (allyl alcohol form) adsorbed on the cooperative active sites, thus to avoid its isomerization to aldehyde form and unexpected C=O hydrogenolysis. Consequently, it enhanced the selectivity to the diol products BDO significantly. Owing to the benign improvement of three center synergy effect, 9Ni1Cu@SiO2 possesses the optimum BYD direct hydrogenation ability with a rarely reported high selectivity of 90.5–94.5 % at 50 °C and 1 MPa.
- Wang, Changzhen,Tian, Yani,Wu, Ruifang,Li, Haitao,Yao, Benzhen,Zhao, Yongxiang,Xiao, Tiancun
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- Quantification of Interfacial pH Variation at Molecular Length Scales Using a Concurrent Non-Faradaic Reaction
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We quantified changes in interfacial pH local to the electrochemical double layer during electrocatalysis by using a concurrent non-faradaic probe reaction. In the absence of electrocatalysis, nanostructured Pt/C surfaces mediate the reaction of H2 with cis-2-butene-1,4-diol to form a mixture of 1,4-butanediol and n-butanol with selectivity that is linearly dependent on the bulk solution pH value. We show that kinetic branching occurs from a common surface-bound intermediate, ensuring that this probe reaction is uniquely sensitive to the interfacial pH value within molecular length scales of the surface. We used the pH-dependent selectivity of this reaction to track changes in interfacial pH during concurrent hydrogen oxidation electrocatalysis and found that the local pH value can vary dramatically (>3 units) relative to the bulk value even at modest current densities in well-buffered electrolytes. This study highlights the key role of interfacial pH variation in modulating inner-sphere electrocatalysis.
- Ryu, Jaeyune,Wuttig, Anna,Surendranath, Yogesh
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- Modelling proposed intermediates in the hydrocarbonylation of alkenes catalysed by rhodium complexes of PBui3 and PPr i3
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In ethanol, hydrocarbonylation reactions of alkenes catalysed by triethylphosphine complexes of rhodium give alcohols as the products with low linear selectivity, whilst rhodium complexes of PPri3 or PBui3 give mainly aldehydes, again with low linear selectivity. Modelling the proposed acyl intermediates by studying [Rh(C(O)Me)(CO)m(L)4-m] (L = PPri3 or PBui3) shows that they exist as monophosphine species under the normal reaction conditions. In the absence of CO, [Rh(=C(OH)Me)(CO) L2]+ can also be formed. The implications of these NMR studies for the chemo- and regio-selectivity of the hydrocarbonylation reactions are discussed. The Royal Society of Chemistry.
- Cheliatsidou, Paraskevi,White, Daniel F. S.,Slawin, Alexandra M. Z.,Cole-Hamilton, David J.
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- DIRECT SYNTHESIS OF 1,4-BUTANEDIOL FROM ALLYL ALCOHOL USING CARBON MONOXIDE AND WATER IN THE PRESENCE OF Rh6(CO)16-PROPANEDIAMINE SYSTEM
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Rh6(CO)16-propanediamine system catalyzes a direct route to 1,4-butanediol from allyl alcohol under the water gas shift reaction condition.Using an aminopyridine in place of the diamine gives γ-butyrolactone in a good yield.
- Kaneda, Kiyotomi,Imanaka, Toshinobu,Teranishi, Shiichiro
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- An unusual reaction of cyclic enol ethers with titanium(III) tetrahydroborate
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Titanium(III) Tetrahydroborate formed in situ from titanium tetrachloride and benzyltriethylammonium tetrahydroborate (1:4) readily reacts with cyclic enol ethers in dichloromethane at -20°C to give the corresponding acyclic diols in high yields after simple aqueous work-up.
- Ravikumar,Chandrasekaran, Srinivasan
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- Alkaline hydrolysis of oligomers of tartrate esters: Effect of a neighboring carboxyl on the reactivity of ester groups
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The importance and the effect of neighboring groups on the hydrolysis of polymeric esters were demonstrated. Several oligomers of poly(butylene tartrate) were synthesized, and their kinetic behavior was studied under alkaline conditions. The oligomers and their degradation products were monitored by HPLC and identified by fast atom bombardment mass spectrometry. The rates of hydrolysis measured at pH 5-8 and at 75 °C indicate that the degradation of the oligomers obeyed pseudo-first-order kinetics. The rate of hydrolysis among the homologous series of oligomers increased as the molecular weight increased. However, the increase in hydrolysis rate was not proportional to the number of ester linkages in the oligomers. This deviation was explained on the basis of electrostatic repulsion of the neighboring carboxylate group toward the hydroxide ion. The calculations revealed that the electrostatic effect was so great that the ester linkage adjacent to the carboxylate anion did not contribute to the overall rate of hydrolysis. The technique presented here can be extended to any multifunctional-group compound that has repeat units and can undergo a specific reaction that can be accurately measured.
- Maniar,Kalonia,Simonelli
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- New environmentally friendly catalysts containing Pd-interstitial carbon made from Pd-glucose precursors for ultraselective hydrogenations in the liquid phase
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We report a novel preparation of a Pd nanocatalyst modified with subsurface C via blending a glucose precursor at the molecular level: the catalyst is demonstrated for the first time to be stereoselective in the hydrogenation of alkynes to cis-alkenes in the liquid phase.
- Chan, Chun Wong Aaron,Xie, Yaling,Cailuo, Nick,Yu, Kai Man Kerry,Cookson, James,Bishop, Peter,Tsang, Shik Chi
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- Zirconium(IV) chloride catalyzed new and efficient protocol for the selective cleavage of p-methoxybenzyl ethers
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A highly selective and efficient method for the unmasking of p-methoxybenzyl (PMB) ethers and esters has been developed by use of 20 mol % of zirconium(IV) chloride as Lewis acid in acetonitrile. The present method is very fast, and the conditions are tolerable to a variety of acid/ base-sensitive protecting groups and substrates such as carbohydrates, terpenes, and amino acids. The products are obtained in good to high yields.
- Madhava Sharma, Gangavaram V.,Reddy, Ch. Govardhan,Krishna, Palakodety Radha
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- Efficient Pd@MIL-101(Cr) hetero-catalysts for 2-butyne-1,4-diol hydrogenation exhibiting high selectivity
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Pd@MIL-101(Cr) hetero-catalysts have been successfully prepared using the metal-organic chemical vapour deposition (MOCVD) approach, by choosing [Pd(η3-C3H5)(η5-C5H5)] as a volatile precursor, and the hydrothermally stable metal-organic framework, MIL-101(Cr) as a support. The prepared Pd@MIL-101(Cr) hetero-catalysts characterized with various analytical techniques, exhibited highly monodispersed immobilized Pd nanoparticles in the MIL-101(Cr) cavities, while retaining the pristine crystallinity and porosity. The intact hybrid Pd@MIL-101(Cr) has been demonstrated to be an efficient catalyst for 2-butyne-1,4-diol hydrogenation with excellent activity, stability and selectivity (2-butene-1,4-diol (>94%)).
- Yin, Dongdong,Li, Chuang,Ren, Hangxing,Shekhah, Osama,Liu, Jinxuan,Liang, Changhai
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- Aqueous phase hydrogenation of acetic acid to ethanol over Ir-MoO x/SiO2 catalyst
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Mo modified Ir/SiO2 (Ir-MoOx/SiO2) was firstly used for the aqueous-phase hydrogenation of acetic acid to ethanol and exhibited the best performance among the investigated catalysts. The synergy effect between the closely contacted Ir and Mo species is responsible for the excellent performance of Ir-MoOx/SiO2. Ir-MoO x/SiO2 is also effective for the hydrogenation of other biomass derived carboxylic acids. Especially when levulinic acid was used as the feedstock, high yields of 2-pentanol (39.0%) and 1,4-pentanediol (42.3%) were obtained simultaneously. To our knowledge, this is the first report about the direct hydrogenation of levulinic acid to 2-pentanol and 1,4-pentanediol over heterogeneous catalyst.
- Wang, Zhiqiang,Li, Guangyi,Liu, Xiaoyan,Huang, Yanqiang,Wang, Aiqin,Chu, Wei,Wang, Xiaodong,Li, Ning
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- Biosynthesis of 1,4-butanediol from erythritol using whole-cell catalysis
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1,4-Butanediol (BDO) biosynthesis from renewable resources is of increasing interest because of global energy and environmental problems. We have previously demonstrated the production of BDO from erythritol by whole-cell catalysis. Here, the effects of several variables on BDO production were investigated, including cell density, temperature, substrate concentration and pH. It was found that the maximum BDO production was obtained at cell density (OD600) of 30. Low temperature and weak alkaline environment were beneficial for the biotransformation. Regarding substrate concentration, 80?g/L of erythritol was found to be optimum for the bioconversion. Under the optimal conditions, the highest concentration of BDO reached 34.5?mg/L, resulting in 5.8-fold increment after optimization. These results will provide useful guidance for enhancing the bioconversion of erythritol to BDO.
- Dai, Lu,Tai, Cui,Shen, Yaling,Guo, Yali,Tao, Fei
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- Raney Ni-Si catalysts for selective hydrogenation of highly concentrated 2-butyne-1,4-diol to 2-butene-1,4-diol
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Raney Ni-Si catalysts were synthesized by treating Raney Ni with silane in a fluidized bed reactor and tested in the selective hydrogenation of 2-butyne-1,4-diol (BYD) at high concentration. Structural characterizations including XRD patterns, TEM images, and X-ray photoelectron spectroscopy show that Raney Ni-Si catalysts are composed of a Ni core surrounded by nickel silicides. These species transform from Ni-rich silicide (Ni2Si) to Si-rich silicide (NiSi2) with increasing silicification temperature from 250 °C to 450 °C. The insertion of Si atoms into Raney Ni catalysts decreased the catalytic activity, but significantly improved the selectivity to 2-butene-1,4-diol (BED). The beneficial effect of Si on the selectivity hydrogenation of BYD may be caused by the presence of Si at Ni-defect sites, and the formation of the surface nickel silicide that suppress the further hydrogenation of BED. Compared with the traditional Lindlar-type catalysts, such Raney Ni-Si materials can be used extensively in organic synthesis for selective hydrogenation of alkynes, avoiding the associated hazards of toxic additives.
- Chen, Xiao,Zhang, Mingming,Yang, Kaixuan,Williams, Christopher T.,Liang, Changhai
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- Kinetics and mechanism of tetrahydrofuran synthesis via 1,4-butanediol dehydration in high-temperature water
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We conducted an experimental investigation into the kinetics and mechanism of tetrahydrofuran synthesis from 1,4-butanediol via dehydration in high-temperature liquid water (HTW) without added catalyst at 200-350 °C. The reaction was reversible, with tetrahydrofuran being produced at an equilibrium yield of 84% (at 200 °C) to 94% (at 350 °C). The addition of CO2 to the reaction mixture increased the reaction rate by a factor of 1.9-2.9, because of the increase in acidity resulting from the formation and dissociation of carbonic acid. This increase was much less than that expected (factor of 37-60) from a previously suggested acid-catalyzed mechanism. This disagreement prompted experiments with added acid (HCl) and base (NaOH) to investigate the influence of pH on the reaction rate. These experiments revealed three distinct regions of pH dependence. At high and low pH, the dehydration rate increased with increasing acidity. At near-neutral pH, however, the rate was essentially insensitive to changes in pH. This behavior is consistent with a mechanism where H2O, in addition to H+, serves as a proton donor. This work indicates that the relatively high native concentration of H+ (large Kw), which has commonly been thought to lead to the occurrence of acid-catalyzed reactions in HTW without added catalyst, does not explain the dehydration of 1,4-butanediol in HTW without catalyst. Rather, H2O serves directly as the proton donor for the reaction.
- Hunter, Shawn E.,Ehrenberger, Carolyn E.,Savage, Phillip E.
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- Highly dispersed palladium nanoclusters incorporated in amino-functionalized silica spheres for the selective hydrogenation of succinic acid to γ-butyrolactone
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Highly dispersed palladium nanoclusters incorporated on amino-functionalized silica sphere surfaces (Pd/SiO2-NH2) were fabricated by a simple one-pot synthesis utilizing 3-(2-aminoethylamino)propyltrimethoxysilane (AAPTS) as coordinating agent. Uniform palladium nanoclusters with an average size of 1.1 nm can be obtained during the co-condensation of tetraethyl orthosilicate and AAPTS owing to the strong interaction between palladium species and amino groups in AAPTS. The palladium particle size can be controlled by addition of AAPTS and plays a significant role in the catalytic performance. The Pd/SiO2-NH2 catalyst exhibits high catalytic activity for succinic acid hydrogenation with 100% conversion and 94% selectivity towards γ-butyrolactone using 1,4-dioxane as solvent at 240°C and 60 bar for 4 h. Moreover, the Pd/SiO2-NH2 catalyst is robust and readily reusable without loss of its catalytic activity.
- You, Chenjia,Zhang, Chi,Chen, Lifang,Qi, Zhiwen
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- Liquid-phase catalytic hydrogenation of 2-butyne-1,4-diol to 1,4-butanediol at atmospheric pressure on suspended catalysts
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The optimum parameters of hydrogenation of 2-butyne-1,4-diol to 1,4-butanediol on the suspended palladium and Ni-Raney catalysts at atmospheric pressure were found. In selected conditions a yield up to 90% of 1,4-butanediol was reached.
- Pyatnitsyna,El'Chaninov
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- Analysis of drugs by pyrolysis. I. Selected ion monitoring combined with a pyrolysis method for the determination of carpronium chloride in biological samples.
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In order to establish an analytical method for carpronium chloride, a parasympathomimetic agent, the pyrolysis reaction of carpronium chloride was examined in a g.c.m.s. system, which revealed that gamma-butyrolactone was produced directly from the drug as the main pyrolysis product. In the case of conversion of [2,2,3,3-2H4]carpronium chloride into the deuterated gamma-butyrolactone, 2H/1H scrambling was observed and confirmed to occur during the pyrolysis process of the deuterated compound. The proportion of gamma-[2H4]butyrolactone among the pyrolysis products was almost independent of the operating conditions, so [2,2,3,3-2H4]carpronium chloride was of practical use as an internal standard for selected ion monitoring. By incorporation of the pyrolysis reaction of carpronium chloride with selected ion monitoring and the use of [2,2,3,3-2H4]carpronium chloride as an internal standard, a rapid, sensitive and selective method was devised for the determination of the drug in biological samples. The method was utilized successfully for the biopharmaceutical studies of carpronium chloride in ma.
- Ohya,Sano
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- Hot Water Induces an Acid-Catalyzed Reaction in Its Undissociated Form
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Hot water in its undissociated form has been kinetically proven to induce a chemical reaction that does not undergo under ambient conditions in the absence of a strong acid. The water-induced and acid-catalyzed rate constants were separately determined for the dehydration of 1,4-butanediol by varying the oxonium ion (H+) concentration. It was found on the kinetic level over a wide range of temperature from moderate to supercritical that the undissociated form of water promotes the reaction at an effective acid concentration of 10-4-10-6 M. A strong density dependence of the reaction rate constant was further observed under supercritical condition, and is related to the anomalous temperature dependence of the rate constant near the critical point.
- Nagai, Yasuharu,Matubayasi, Nobuyuki,Nakahara, Masaru
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- Selective Hydrogenation of Cyclic Ester to α,ω-Diol Catalyzed by Cationic Ruthenium Complexes with Trialkylphosphine Ligands
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Cyclic esters like γ-butyrolactone were smoothly hydrogenated in the presence of a series of ruthenium complexes with trialkylphosphine ligands under mild conditions to afford the corresponding α,ω-diols with high selectivity.The ruthenium complexes prepared in the presence of additional NH4PF6 or H3PO4 turned out to have the superior catalytic activity.
- Hara, Yoshinori,Inagaki, Hiroko,Nishimura, Sugio,Wada, Keisuke
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- Pt nanoparticles over TiO2-ZrO2 mixed oxide as multifunctional catalysts for an integrated conversion of furfural to 1,4-butanediol
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1,4-butanediol (BDO) is an important commodity chemical for manufacturing many basic chemicals and valuable polymers. Its current manufacturing processes are exclusively based on feedstocks derived from oil and natural gas. The biomass-to-BDO chemical transformation is via furfural, a key platform molecule from glucose and xylose. The integrated conversion involves two sequent reaction steps: selective oxidation of furfural to furanones and hydrogenation of the mixture of furanones to BDO. Platinum nanoparticles supported over TiO 2-ZrO2 perform well for both oxidation and hydrogenation steps and the total yield of BDO reaches 85.2%. The chemical composition and crystallinity of the mixed oxide support significantly affect the catalytic performance. The best catalyst is platinum supported over TiO 2-ZrO2 mixed oxide (Ti/Zr, 1:1) calcined at 823 K, which also exhibits good recoverability and recyclability in the five-run test.
- Li, Fengbo,Lu, Tao,Chen, Bingfeng,Huang, Zhijun,Yuan, Guoqing
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Read Online
- Tracking Electrical Fields at the Pt/H2O Interface during Hydrogen Catalysis
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We quantify changes in the magnitude of the interfacial electric field under the conditions of H2/H+ catalysis at a Pt surface. We track the product distribution of a local pH-sensitive, surface-catalyzed nonfaradaic reaction, H2 addition to cis-2-butene-1,4-diol to form n-butanol and 1,4-butanediol, to quantify the concentration of solvated H+ at a Pt surface that is constantly held at the reversible hydrogen electrode potential. By tracking the surface H+ concentration across a wide range of pH and ionic strengths, we directly quantify the magnitude of the electrostatic potential drop at the Pt/solution interface and establish that it increases by 60 mV per unit increase in pH. These results provide direct insight into the electric field environment at the Pt surface and highlight the dramatically amplified field existent under alkaline vs acidic conditions.
- Ryu, Jaeyune,Surendranath, Yogesh
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Read Online
- First example of borirane synthesis by α-olefins reaction with BCl3·SMe2 Catalyzed with (η5-C5H5)2TiCl2
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New method was developed of the synthesis of 2-phenyl(alkyl, benzyl, phenoxy)-1-chloroboriranes via reaction of α-olefins with BCl3·SMe2 catalyzed by Cp2TiCl2. The method is based on the boracyclopropanes (boriranes) formation resulting from transmetallation of titanacyclopropanes arising from the reaction of α-olefins with Cp2TiCl2. The calculations were fulfilled of thermodynamic and activation parameters of possible reaction routes.
- Khusainova,Khafizova,Tyumkina,Dzhemilev
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Read Online
- Converging conversion - using promiscuous biocatalysts for the cell-free synthesis of chemicals from heterogeneous biomass
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Production of chemicals from lignocellulosic biomass has been proposed as a suitable replacement to petrochemicals. However, one inherent challenge of biomass utilization is the heterogeneity of the substrate resulting in the presence of mixed sugars after hydrolysis. Fermentation of mixed sugars often leads to poor yield and generation of multiple by-products, thus complicating the subsequent downstream processing. System biocatalysis has thus been developed in recent years to address this challenge. In this work, several novel enzymes with broad substrate promiscuity were identified using a sequence-based discovery approach as suitable biocatalysts in a conversion ofd-xylose andl-arabinose, two major constituents of hemicellulose found in plant biomass. These promiscuous enzymes enabled simultaneous biotransformation ofd-xylose andl-arabinose to yield 1,4-butanediol (BDO) with a maximum production rate of 3 g L?1h?1and a yield of >95%. This model system was further adapted toward the production of α-ketoglutarate (2-KG) from the pentoses using O2as a cosubstrate for cofactor recycling reaching a maximum production rate of 4.2 g L?1h?1and a yield of 99%. To verify the potential applicability of our system, we attempted to scale up the BDO and 2-KG production fromd-xylose andl-arabinose. Simple optimization and reaction engineering allowed us to obtain BDO and 2-KG titers of 18 g L?1and 42 g L?1, with theoretical yields of >75% and >99%, respectively. One of the promiscuous enzymes identified together with auxiliary promiscuous enzymes was also suitable for stereoconvergent synthesis from a mixture ofd-glucose andd-galactose, predominant sugars found in food waste streams and microalgae biomass.
- Pick, André,Sieber, Volker,Sutiono, Samuel
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Read Online
- Reductive cleavage of tert-butyldimethylsilyl ether via intramolecular transfer of hydride
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The cleavage of α-hydroxy tert-butyldimethylsilyl ether to diol takes place efficiently with LAH. It has been proposed that the reaction proceeds via intramolecular hydride transfer from the alkoxy aluminium hydride. In order to substantiate this, reduction of TBDMS ether with LAH in a variety of substrates was studied.
- Saravanan, Parthasarathy,Gupta, Suparna,DattaGupta, Arpita,Gupta, Sonia,Singh, Vinod K.
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Read Online
- Catalytic hydrogenation of 2-butyne-1,4-diol to 2-butene-1,4-diol at atmospheric pressure in the liquid phase
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Selective hydrogenation of 2-butyne-1,4-diol to 2-butene-1,4-diol on suspended palladium and Raney nickel catalysts at atmospheric pressure was studied. The optimal parameters of this reaction were determined. Samples containing 90% 2-butene-1,4-diol were
- Pyatnitsyna,El'chaninov,Savost'yanov
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Read Online
- A synthesis method of diol
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The present invention belongs to the field of organic synthesis technology, specifically a synthesis method of a diol; the present invention by bis (trimethylsilyl) lithium amino catalytic lactone boronization of lactone to synthesize a variety of structure of the diol compound; specifically, under the bis (trimethylsilyl) amino lithium catalytic system, to a variety of lactone compounds and pinacol borane as raw materials, the preparation of diol compounds; the method of the present invention raw materials are of a wide range of sources or easy to prepare, easy to operate, selective and controllable, high yield, mild conditions, universality wide.
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Paragraph 0043-0048
(2022/01/12)
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- Method for producing a shaped catalyst body
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Provided herein is a novel process for producing shaped catalyst bodies in which a mixture having aluminum contents of Al±0 in the range from 80 to 99.8% by weight, based on the mixture used, is used to form a specific intermetallic phase, shaped catalyst bodies obtainable by the process of the invention, a process for producing an active catalyst fixed bed including the shaped catalyst bodies provided herein, the active catalyst fixed beds and also the use of these active catalyst fixed beds for the hydrogenation of organic hydrogenatable compounds or for formate degradation.
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Page/Page column 29-30
(2021/11/19)
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- Hydroboration Reaction and Mechanism of Carboxylic Acids using NaNH2(BH3)2, a Hydroboration Reagent with Reducing Capability between NaBH4and LiAlH4
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Hydroboration reactions of carboxylic acids using sodium aminodiboranate (NaNH2[BH3]2, NaADBH) to form primary alcohols were systematically investigated, and the reduction mechanism was elucidated experimentally and computationally. The transfer of hydride ions from B atoms to C atoms, the key step in the mechanism, was theoretically illustrated and supported by experimental results. The intermediates of NH2B2H5, PhCH= CHCOOBH2NH2BH3-, PhCH= CHCH2OBO, and the byproducts of BH4-, NH2BH2, and NH2BH3- were identified and characterized by 11B and 1H NMR. The reducing capacity of NaADBH was found between that of NaBH4 and LiAlH4. We have thus found that NaADBH is a promising reducing agent for hydroboration because of its stability and easy handling. These reactions exhibit excellent yields and good selectivity, therefore providing alternative synthetic approaches for the conversion of carboxylic acids to primary alcohols with a wide range of functional group tolerance.
- Wang, Jin,Ju, Ming-Yue,Wang, Xinghua,Ma, Yan-Na,Wei, Donghui,Chen, Xuenian
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p. 5305 - 5316
(2021/04/12)
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- MOF-derived hcp-Co nanoparticles encapsulated in ultrathin graphene for carboxylic acids hydrogenation to alcohols
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Highly efficient conversion of carboxylic acids to valuable alcohols is a great challenge for easily corroded non-noble metal catalysts. Here, a series of few-layer graphene encapsulated metastable hexagonal closed-packed (hcp) Co nanoparticles were fabricated by reductive pyrolysis of metal-organic framework precursor. The sample pyrolyzed at 400 °C (hcp-Co@G400) presented outstanding performance and stability for converting a variety of functional carboxylic acids and its turnover frequency was one magnitude higher than that of conventional facc-centered cubic (fcc) Co catalysts. In situ DRIFTS spectroscopy of model reaction acetic acid hydrogenation and DFT calculation results confirm that carboxylic acid initially undergoes dehydroxylation to RCH2CO* followed by consecutive hydrogenation to RCH2CH2OH through RCH2COH*. Acetic acid prefers to vertically adsorb at hcp-Co (0 0 2) facet with a much lower adsorption energy than parallel adsorption at fcc-Co (1 1 1) surface, which plays a key role in decreasing the activation barrier of the rate-determining step of acetic acid dehydroxylation.
- Dong, Mei,Fan, Weibin,Gao, Xiaoqing,Zhu, Shanhui
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p. 201 - 211
(2021/06/03)
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- Hydrodeoxygenation of C4-C6 sugar alcohols to diols or mono-alcohols with the retention of the carbon chain over a silica-supported tungsten oxide-modified platinum catalyst
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The hydrodeoxygenation of erythritol, xylitol, and sorbitol was investigated over a Pt-WOx/SiO2 (4 wt% Pt, W/Pt = 0.25, molar ratio) catalyst. 1,4-Butanediol can be selectively produced with 51% yield (carbon based) by erythritol hydrodeoxygenation at 413 K, based on the selectivity over this catalyst toward the regioselective removal of the C-O bond in the -O-C-CH2OH structure. Because the catalyst is also active in the hydrodeoxygenation of other polyols to some extent but much less active in that of mono-alcohols, at higher temperature (453 K), mono-alcohols can be produced from sugar alcohols. A good total yield (59%) of pentanols can be obtained from xylitol, which is mainly converted to C2 + C3 products in the literature hydrogenolysis systems. It can be applied to the hydrodeoxygenation of other sugar alcohols to mono-alcohols with high yields as well, such as erythritol to butanols (74%) and sorbitol to hexanols (59%) with very small amounts of C-C bond cleavage products. The active site is suggested to be the Pt-WOx interfacial site, which is supported by the reaction and characterization results (TEM and XAFS). WOx/SiO2 selectively catalyzed the dehydration of xylitol to 1,4-anhydroxylitol, whereas Pt-WOx/SiO2 promoted the transformation of xylitol to pentanols with 1,3,5-pentanetriol as the main intermediate. Pre-calcination of the reused catalyst at 573 K is important to prevent coke formation and to improve the reusability.
- Betchaku, Mii,Cao, Ji,Liu, Lujie,Nakagawa, Yoshinao,Tamura, Masazumi,Tomishige, Keiichi,Yabushita, Mizuho
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supporting information
p. 5665 - 5679
(2021/08/16)
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- Conversion of succinic acid over Ni and Co catalysts
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Liquid-phase hydrogenation of succinic acid (SA) over supported Ni and Co catalysts was investigated at 200 °C and 6 MPa of H2. Reduced and passivated catalysts with the same surface metal density (2.5 atoms of metal per nm2 of support) were prepared by incipient wetness impregnation. The catalysts were characterized by X-ray diffraction (XRD), N2 adsorption, X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR), CO-chemisorption, and temperature-programmed desorption of NH3 (TPD-NH3). The Ni and Co catalysts supported over SiO2 showed different product distribution, due to the adsorption of the SA over the surface of catalysts, determined by DFT calculations. The Co/SiO2, Co/SiO2-Al2O3, and Co/Al2O3 catalysts showed different product distribution, which was correlated with total acidity from TPD-NH3 results. In general, the Co catalysts promoted the hydrogenation process; however, the highest total acidity showed by Co/Al2O3 also promoted the dehydration process. Finally, the initial rate follows the trend according to the dispersion determined by CO-chemisorption.
- Rojas, Mabel,Zarate, Ximena,Canales, Roberto I.,Dongil, Ana Belen,Pazo, Cesar,Saavedra-Torres, Mario,Escalona, Néstor
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p. 165 - 176
(2020/05/14)
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- Hydroformylation reaction ligand, hydroformylation catalyst and diol preparation method
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The invention discloses a hydroformylation reaction ligand, a hydroformylation catalyst and a diol preparation method According to the invention, the structural formula of the hydroformylation reaction ligand is shown in the specification, wherein R1 and R2 are mutually independent one of H, aryl or substituted aryl, thienyl, pyrrolyl, thiazolyl, imidazolyl and pyridyl; the ligand disclosed by the invention is high in catalytic activity and good in metal active center stability, by-products of aldehyde in a conventional hydroformylation reaction can be reduced, and linear diol with a high normal/isomer ratio can be obtained by a one-step method; and the method has the advantages of simple and convenient process, low cost and energy consumption, good production safety, high product quality and the like, and is particularly suitable for large-scale industrial production.
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Paragraph 0061; 0067-0068; 0081
(2021/06/22)
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- Synthetic method of linear dihydric alcohol
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The invention discloses a synthetic method of linear dihydric alcohol. The synthetic method comprises the following steps: (1) carrying out hydrosilylation reaction on alpha-olefin and siloxane to obtain alkyl siloxane; (2) carrying out hydroxymethylation reaction on alkyl siloxane, organic metal alkali and a hydrogen acceptor to obtain silyl alcohol; and (3) carrying out oxidation reaction on the silyl alcohol, fluorine-containing metal salt and peroxide to obtain the linear dihydric alcohol. The method has the advantages of mild process, easily available raw material sources, no need of post-treatment after the reaction is completed, capability of being directly used for the next reaction, simplification of the process flow, high conversion rate, high selectivity, low cost and suitability for large-scale production.
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Paragraph 0104-0105; 0108-0110
(2021/09/01)
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- Ultrastable Cu Catalyst for CO2 Electroreduction to Multicarbon Liquid Fuels by Tuning C–C Coupling with CuTi Subsurface
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Production of multicarbon (C2+) liquid fuels is a challenging task for electrocatalytic CO2 reduction, mainly limited by the stabilization of reaction intermediates and their subsequent C?C couplings. In this work, we report a unique catalyst, the coordinatively unsaturated Cu sites on amorphous CuTi alloy (a-CuTi@Cu) toward electrocatalytic CO2 reduction to multicarbon (C2-4) liquid fuels. Remarkably, the electrocatalyst yields ethanol, acetone, and n-butanol as major products with a total C2-4 faradaic efficiency of about 49 % at ?0.8 V vs. reversible hydrogen electrode (RHE), which can be maintained for at least 3 months. Theoretical simulations and in situ characterization reveals that subsurface Ti atoms can increase the electron density of surface Cu sites and enhance the adsorption of *CO intermediate, which in turn reduces the energy barriers required for *CO dimerization and trimerization.
- Duan, Chongxiong,Duan, Delong,Hu, Fei,Jiang, Jun,Jiang, Yawen,Kong, Tingting,Liu, Qi,Long, Ran,Lv, Xuefeng,Wang, Xiaonong,Xiong, Yujie,Yang, Li,Zeng, Longjiao
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supporting information
p. 26122 - 26127
(2021/11/12)
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- METHOD FOR PRODUCING ALCOHOL
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PROBLEM TO BE SOLVED: To provide a method for producing selectively alcohol from carboxylic acid under mild conditions. SOLUTION: In the presence of a catalyst with M1 and M2 as metal species supported on a support, a substrate is reduced to produce a corresponding alcohol. (M1 is Rh, Pt, Ru, Ir, or Pd; M2 is Sn, V, Mo, W, or Re; the support is ZrO2, hydroxyapatite, Nb2O5, fluoroapatite, or hydrotalcite; the substrate is the formula 1a, 1b, or 1c). SELECTED DRAWING: None COPYRIGHT: (C)2020,JPO&INPIT
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Paragraph 0101-0108; 0114; 0116; 0122; 0127-0128
(2020/11/26)
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- TiO2supported Ru catalysts for the hydrogenation of succinic acid: Influence of the support
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Succinic acid is a valuable biomass-derived platform molecule, which can be further catalytically converted into many industrially relevant molecules such as γ-butyrolactone, 1,4-butanediol or tetrahydrofuran. The influence of the support nature on both the activity of Ru/TiO2 catalysts and the selectivity pattern in the hydrogenation of succinic acid was investigated, with focus on the metal-support interaction, the crystallographic structure of the TiO2 support and the supported Ru nanoparticle size features. We showed that the catalyst activity was related to both the Ru particle size and the metal support interaction, those features being induced by the presence of the rutile phase within the TiO2 support and by the preparation method of the supported Ru particles. The rutile phase not only favors the formation of small Ru particles but also promotes stronger metal-support interaction compared with the anatase polymorph. Strong interactions between metal and support can also be formed via thermal reduction in contrast to low-temperature direct chemical reduction. Interestingly, a low temperature solar photon-assisted synthesis method facilitates very high succinic acid conversion, by enabling the stabilization of 1.8 nm small-size Ru nanoparticles in the absence of any rutile phase within the TiO2 support. This journal is
- Brzezinska, Magdalena,Keller, Nicolas,Louven, Yannik,Niemeier, Johannes,Palkovits, Regina,Ruppert, Agnieszka M.
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p. 6860 - 6869
(2020/11/09)
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- Olefin reaction in the catalyst and the olefin production
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PROBLEM TO BE SOLVED: To provide a catalyst for obtaining an olefin in high selectivity with a vicinal diol as a raw material.SOLUTION: A catalyst for olefination reaction for use in a reaction to produce an olefin by a reaction of a polyol, having two adjacent carbon atoms each having a hydroxy group, with hydrogen comprises: a carrier; at least one oxide selected from the group consisting of oxides of the group 6 elements and oxides of the group 7 elements supported on the carrier; and at least one metal selected from the group consisting of silver, iridium, and gold supported on the carrier.SELECTED DRAWING: None
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Paragraph 0109; 0118-0119; 0124-0125;0129-0132; 0134; ...
(2020/10/31)
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- Manganese catalyzed selective hydrogenation of cyclic imides to diols and amines
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Herein we report the selective hydrogenation of cyclic imides to diols and amines, homogeneously catalyzed for the first time by a complex of an earth-abundant metal, a manganese pincer complex. A plausible catalytic cycle is proposed based on informative mechanistic experiments.
- Das, Uttam Kumar,Janes, Trevor,Kumar, Amit,Milstein, David
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supporting information
p. 3079 - 3082
(2020/06/19)
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- One-pot synthesis of 1,3-butanediol by 1,4-anhydroerythritol hydrogenolysis over a tungsten-modified platinum on silica catalyst
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Chemical production of 1,3-butanediol from biomass-derived compounds was first reported by 1,4-anhydroerythritol hydrogenolysis over a Pt-WOx/SiO2 catalyst. The reaction proceeded by ring opening hydrogenolysis of 1,4-anhydroerythritol followed by selective removal of secondary OH groups in 1,2,3-butanetriol, and an overall 1,3-butanediol yield up to 54% was then obtained. The performance of the Pt-WOx/SiO2 catalyst for 1,4-anhydroerythritol hydrogenolysis was closely correlated with that for glycerol hydrogenolysis to 1,3-propanediol. The optimized Pt-WOx/SiO2 (Pt: 4 wt% and W: 0.94 wt%) catalyst showed 57% yield of 1,3-propanediol.
- Asano, Takehiro,Liu, Lujie,Nakagawa, Yoshinao,Tamura, Masazumi,Tomishige, Keiichi
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supporting information
p. 2375 - 2380
(2020/05/14)
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- Effects of a forming process on the properties and structure of RANEY-Ni catalysts for the hydrogenation of 1,4-butenediol
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Three commercial Ni-Al alloys formed by a vacuum atomization method (NAV), atmospheric atomization method (NAA) and high-temperature melting method (NAH) were leached by 10 wt% NaOH solution to prepare three RANEY-Ni catalysts (RNAV, RNAA and RNAH, correspondingly). The effects of a forming process on the structure of Ni-Al alloys and the corresponding RANEY-Ni catalysts were investigated via XRD, XPS, SEM, TEM, NH3-TPD, N2 adsorption-desorption and EDX-mapping studies. Also, the as-prepared RANEY-Ni catalysts were evaluated via the hydrogenation of 1,4-butenediol (BED) to produce 1,4-butanediol (BDO). The results showed that the specific surface areas and surface morphologies of the Ni-Al alloys present significant differences. Meanwhile, the RNAA sample presented a comparatively regular morphology, similar to a small piece of sugar cane. The weak and medium acid peak areas of the RNAA catalyst were lower than those of the other samples. RNAV showed higher weak and medium acid peak areas, demonstrating the higher number of acid centers on the surface of the catalyst. The surface of the RNAA catalyst obtained from NAA contained more active component-Ni, about 90 wt% on the surface, and the specific surface area of the sample was 75 times that of its precursor Ni-Al alloy powder (NAA). The evaluation results present that the RNAA catalyst shows better hydrogenation performance, with BED conversion of 100%, both BDO selectivity and yield of 46.11%.
- Fan, Xing,Gao, Xianlong,Ma, Fengyun,Mo, Wenlong,Noritatsu, Tsubaki,Wu, Hongli
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p. 5516 - 5524
(2020/02/22)
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- Novel clamp metal complex and application thereof
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The invention discloses a method for preparing a novel clamp-shaped complex and application of the novel clamp-shaped complex in the reaction of catalytic hydrogenation of carboxylic acid ester compounds to produce corresponding alcohols and reaction of carbon dioxide catalytic hydrogenation to form formamide compounds. Carboxylic acid esters and hydrogen as raw materials or carbon dioxide, hydrogen and amine compounds as raw materials are reacted in an organic solvent condition or a solvent-free condition in the presence of a transition metal complex as a catalyst to respectively form the corresponding alcohol compounds and/or corresponding formamide compounds. The method has the advantages of being high in reaction efficiency, good in selectivity, mild in conditions, economical, environmentally-friendly, and simple in operation, and has good promotion and application prospects.
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Paragraph 0410-0412; 0454-0457
(2019/04/26)
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- Metal complex and preparation method and application thereof
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The invention discloses a post-transition metal bisphosphine diamine complex catalyst which is good in substrate applicability, and capable of efficiently catalyzing a hydrogenation alcohol productionreaction of various carbonyl derivatives such as esters, amides and carbonates different in structure. Central metal coordination of the metal complex catalyst has two diaminodiphosphine ligands o-PPh2C6H4NR1R2 and Ph2PCH2CH2NR3R4 (or o-PPh2C6H4CH2NR3R4, Ph2P(CH2) 3NR3R4) different in structure, and the metal complex can be obtained through a simple two-step synthesis method. The catalysts show the advantages of the two ligands in the catalytic hydrogenation process, and the defects of a complex catalyst formed by a single ligand in the aspect of applicability of substrates can be effectivelyovercome.
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Paragraph 0034; 0049
(2019/06/07)
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- Olefin-tethered organoruthenium carbene complexes: Synthesis, X-ray structure and catalytic insights on hydrogenation of esters
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A series of Ru(II) complexes encompassing imidazolylidene olefin arm have been designed. The newly synthesized ligands and complexes were fully characterized by 1H, 13C NMR, and elemental analyses. Structural geometry for one of the envoy Ru(II) carbene complexes 3a was confirmed by single-crystal X-ray diffraction studies. The complexes acquired a distorted octahedral geometry. The highly active [Ru(II)-NHC] complex 3b, showed excellent catalytic performance for the hydrogenation of esters in 1,4-dioxane medium. The effects of solvent, base, wingtip substituents, time and catalyst loading were also investigated. The reported catalyst performed exceptionally well for a range of esters and furnishes very good yield of hydrogenated products.
- Nirmala, Muthukumaran,Murugan, Kaliyappan,Vijayapritha, Subbarayan,Viswanathamurthi, Periasamy,Bertani, Roberta,Malecki, Jan Grzegorz
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- Metal complex catalyst as well as preparation method and application thereof (by machine translation)
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The invention provides a phosphine amine, diamine ligand transition metal complex catalyst containing a secondary amine functional group and a preparation method and application, and relates to a carbonyl derivative molecular hydrogenation alcohol metal complex catalyst capable of efficiently catalyzing ester, aldehyde, ketone and the like under the condition of lower additive usage. O-PPh coordinated with catalyst metal center2 C6 H4 NHR1 Ligands and o-PPh2 C6 H4 NHR2 Ligands or o-PPh2 C6 H4 NHR1 Ligands and R2 HNNCH2 CH2 NHR3 Ligands, which can be prepared by a simple two-step synthesis method. In the process of participating in the catalytic hydrogenation reaction, only a small amount of auxiliary "base" is needed to obtain excellent catalytic hydrogenation performance, and the defect. (by machine translation)
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Paragraph 0038; 0075
(2019/07/29)
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- Ruthenium complexes with N-functionalized secondary amino ligands: a new class of catalysts toward efficient hydrogenation of esters
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A series of ruthenium complexes (o-PPh2C6H4NHR)2RuCl2 (R = Me, 3; Et, 4; CH2Ph, 5) and (o-PPh2C6H4NH2)[(CH2NHR)2]RuCl2 (R = Me, 7; Et, 8; iPr, 9) modulated with mono-N-functionalized secondary amino ligands were synthesized and demonstrated as efficient catalysts in the hydrogenation of esters into alcohols. The catalytic performances of these new complexes are much better than their corresponding primary amino ligand-constituted complexes (o-PPh2C6H4NH2)2RuCl2 (2) and (o-PPh2C6H4NH2)[(CH2NH2)2]RuCl2 (6). The significant improvement is attributed to the increased electron density of the secondary amino ligand in comparison with that of the primary amino ligand.
- Fang, Xiaolong,Li, Bin,Zheng, Jianwei,Wang, Xiaoping,Zhu, Hongping,Yuan, Youzhu
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supporting information
p. 2290 - 2294
(2019/02/19)
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- TETRADENTATE LIGAND, AND PRODUCTION METHOD THEREFOR, SYNTHETIC INTERMEDIATE THEREOF, AND TRANSITION METAL COMPLEX THEREOF
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The present invention relates to: a compound as a ligand in a variety of catalytic organic synthetic reactions; a method for producing the compound; a synthetic intermediate of the compound; and a transition metal complex which has the compound as a ligand. The compound includes a compound represented by the following general formula (1A):
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Paragraph 0284-0286
(2019/05/15)
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- General and Phosphine-Free Cobalt-Catalyzed Hydrogenation of Esters to Alcohols
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Catalytic hydrogenation of esters is essential for the sustainable production of alcohols in organic synthesis and chemical industry. Herein, we describe the first non-noble metal catalytic system that enables an efficient hydrogenation of non-activated esters to alcohols in the absence of phosphine ligands (with a maximum turnover number of 2391). The general applicability of this protocol was demonstrated by the high-yielding hydrogenation of 39 ester substrates including aromatic/aliphatic esters, lactones, polyesters and various pharmaceutical molecules.
- Shao, Zhihui,Zhong, Rui,Ferraccioli, Raffaella,Li, Yibiao,Liu, Qiang
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supporting information
p. 1125 - 1130
(2019/10/22)
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- Preparation of a Series of Supported Nonsymmetrical PNP-Pincer Ligands and the Application in Ester Hydrogenation
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In contrast to their symmetrical analogues, nonsymmetrical PNP-type ligand motifs have been less investigated despite the modular pincer structure. However, the introduction of mixed phosphorus donor moieties provides access to a larger variety of PNP ligands. Herein, a facile solid-phase synthesis approach towards a diverse PNP-pincer ligand library of 14 members is reported. Contrary to often challenging workup procedures in solution-phase, only simple workup steps are required. The corresponding supported ruthenium-PNP catalysts are screened in ester hydrogenation. Usually, industrially applied heterogeneous catalysts require harsh conditions in this reaction (250–350 °C at 100–200 bar) often leading to reduced selectivities. Heterogenized reusable Ru-PNP catalysts are capable of reducing esters and lactones selectively under mild conditions.
- Konrath, Robert,Spannenberg, Anke,Kamer, Paul C. J.
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supporting information
p. 15341 - 15350
(2019/11/14)
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- Preparation of Highly Active Monometallic Rhenium Catalysts for Selective Synthesis of 1,4-Butanediol from 1,4-Anhydroerythritol
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1,4-Butanediol can be produced from 1,4-anhydroerythritol through the co-catalysis of monometallic mixed catalysts (ReOx/CeO2+ReOx/C) in the one-pot reduction with H2. The highest yield of 1,4-butanediol was over 80 %, which is similar to the value obtained over ReOx–Au/CeO2+ReOx/C catalysts. Mixed catalysts of CeO2+ReOx/C showed almost the same performance, giving 89 % yield of 1,4-butanediol. The reactivity trends of possible intermediates suggest that the reaction mechanism over ReOx/CeO2+ReOx/C is similar to that over ReOx–Au/CeO2+ReOx/C: deoxydehydration (DODH) of 1,4-anhydroerythritol to 2,5-dihydrofuran over ReOx species on the CeO2 support with the promotion of H2 activation by ReOx/C, isomerization of 2,5-dihydrofuran to 2,3-dihydrofuran catalyzed by ReOx on the C support, hydration of 2,3-dihydrofuran catalyzed by C, and hydrogenation to 1,4-butanediol catalyzed by ReOx/C. The reaction order of conversion of 1,4-anhydroerythritol with respect to H2 pressure is almost zero and this indicates that the rate-determining step is the formation of 2,5-dihydrofuran from the coordinated substrate with reduced Re in the DODH step. The activity of ReOx/CeO2+ReOx/C is higher than that of ReOx–Au/CeO2+ReOx/C, which is probably related to the reducibility of ReOx/C and the mobility of the Re species between the supports. High-valent Re species such as Re7+ on the CeO2 and C supports are mobile in the solvent; however, low-valent Re species, including metallic Re species, have much lower mobility. Metallic Re and cationic low-valent Re species with high reducibility and low mobility can be present on the carbon support as a trigger for H2 activation and promoter of the reduction of Re species on CeO2. The presence of noble metals such as Au can enhance the reducibility through the activation of H2 molecules on the noble metal and the formation of spilt-over hydrogen over noble metal/CeO2, as indicated by H2 temperature-programmed reduction. The higher reducibility of ReOx–Au/CeO2 lowers the DODH activity of ReOx–Au/CeO2+ReOx/C in comparison with ReOx/CeO2+ReOx/C by restricting the movement of Re species from C to CeO2.
- Wang, Tianmiao,Tamura, Masazumi,Nakagawa, Yoshinao,Tomishige, Keiichi
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p. 3615 - 3626
(2019/07/15)
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- Diaminodiphosphine tetradentate ligand and ruthenium complex thereof, and preparation methods and applications of ligand and complex
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The invention discloses a diaminodiphosphine tetradentate ligand and a ruthenium complex thereof, and preparation methods and applications of the ligand and the complex, and provides a ruthenium complex represented by a formula I, wherein L is a diaminodiphosphine tetradentate ligand represented by a formula II, and X and Y are respectively and independently chlorine ion, bromine ion, iodine ion,hydrogen negative ion or BH4. According to the present invention, the ruthenium complex exhibits excellent catalytic activity in the catalytic hydrogenation reactions of ester compounds, has high yield and high chemical selectivity, is compatible with conjugated and non-conjugated carbon-carbon double bond, carbon-carbon triple bond, epoxy, halogen, carbonyl and other functional groups, and hasgreat application prospects.
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Paragraph 0301-0303; 0306
(2019/11/04)
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- Preparation method of 1,4-butanediol and dicarboxylic acid ester thereof
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The invention relates to a preparation method of 1,4-butanediol and a dicarboxylic acid ester thereof. Specifically, the preparation method of 1,4-butanediol and the dicarboxylic acid ester thereof comprises the following steps: performing hydrodecarbonylation esterification ring-opening on a furoic acid compound, a trifluoromethanesulfonate, a hydrogenation catalyst in a carboxylic acid solvent to obtain a 1,4-butanediol dicarboxylic acid ester. The method has the characteristics of simple process, easy purification, high yield, green safety, and the like, and is suitable for large-scale industrial production.
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Paragraph 0056; 0058
(2019/10/01)
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- METHOD FOR HYDROGENATING CARBOXYLIC ACIDS IN ORDER TO FORM ALCOHOLS
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Process for the continuous hydrogenation of a carboxylic acid (I) to an alcohol (II) by means of hydrogen at a temperature of from 100 to 300° C. and a pressure of 10 to 33 MPa abs in a reactor tube through which axial flow occurs and which has a fixed-bed catalyst which is fixed therein and comprises at least one element from the group consisting of Re, Co and Cu, and in which the carboxylic acid (I) to be hydrogenated is present in a liquid mixture (Ill) comprising the carboxylic acid (I), water and alcohol (II), where the mixture (Ill) has an acid number of from 0.2 to 25 mg KOH/g and comprises at least 15% by weight of water and at least 20% by weight of alcohol (II) and the flow velocity of the flowing liquid calculated on the basis of the geometric cross-sectional area of the empty, catalyst-free reactor tube is from 10 to 50 m/h.
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Paragraph 0148-0157
(2019/04/30)
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- TiO2-supported molybdenum carbide: An active catalyst for the aqueous phase hydrogenation of succinic acid
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TiO2-supported Mo carbides “MoC/TiO2” were prepared by impregnation of Mo salt followed by temperature programmed reduction-carburization using 20% v/v C2H6/H2. Catalysts were characterized by XRD, XPS, TEM, STEM, ICP, Raman, BET, and carbon elemental analysis. The catalytic activity was evaluated for aqueous phase hydrogenation of succinic acid at 160–240 °C, and 90–150 bar of H2 in batch reactor. MoC/TiO2 is active for this reaction. The main products after 24 h are γ-butyrolactone, and more remarkably butyric acid. These intermediates are then converted to tetrahydrofuran, butanol, 1,4-butanediol and butane. The reaction conditions (temperature, pressure) do not impact the products distribution. A larger amount of butyric acid is formed when catalysts were synthesized with a higher gas hourly space velocity. The deactivation observed while recycling the catalyst was mainly attributed to a decrease in the amounts of carbidic molybdenum and carbidic carbon, as demonstrated by XPS analysis.
- Abou Hamdan, Marwa,Loridant, Stéphane,Jahjah, Mohamad,Pinel, Catherine,Perret, Noémie
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- PHENANTHROLINE BASED PINCER COMPLEXES USEFUL AS CATALYSTS FOR THE PREPARATION OF METHANOL FROM CARBONDIOXIDE
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The present invention relates to a novel phenonthroline based pincer complexes and process for preparation thereof. The present invention also provides a one pot process for the conversion of carbon dioxide to methanol in the presence of a molecularly defined pincer-type single-site Ru-catalyst and secondary amine. Further the present invention provides the use of phenonthroline based pincer complexes for the esterification of alcohols and hydrogenation of esters under mild conditions.
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Paragraph 0134
(2018/04/02)
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- Cobalt Pincer Complexes for Catalytic Reduction of Carboxylic Acid Esters
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A selection of cobalt(I) and cobalt(II) pincer type complexes with different substitution patterns was tested in the catalytic reduction of carboxylic acid esters to alcohols. The cobalt pincer type complex 4 is suitable for the hydrogenation of aromatic as well as aliphatic and cyclic esters. Mechanistic investigation indicated a metal ligand cooperated reaction pathway.
- Junge, Kathrin,Wendt, Bianca,Cingolani, Andrea,Spannenberg, Anke,Wei, Zhihong,Jiao, Haijun,Beller, Matthias
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supporting information
p. 1046 - 1052
(2018/01/01)
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- PROCESS AND CATALYST FOR PREPARING 1,4-BUTANEDIOL
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The present invention relates to a process for preparing 1,4-butanediol (BDO) by hydrogenating 2-butyne-1,4-diol (BYD) or 4-hydroxybutanal (4-HBA) in the presence of a catalyst of the Raney type having a porous foam structure, wherein the macroscopic pores have sizes in the range of 100 to 5000 μm, and a bulk density of up to 0.8 kg/L.
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Page/Page column 9; 10; 11
(2018/04/17)
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- Method for preparing 1,4-butanediol by using two-section hydrogenation of 1,4-butynediol
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The invention discloses a method for preparing 1,4-butanediol by using two-section hydrogenation of 1,4-butynediol. The method comprises the following steps of a, enabling 1,4-butanediol to contact anamorphous nickel alloy catalyst in a one-section hydrogenation reactor, performing one-section hydrogenation reaction, and separating solid and liquid, so as to obtain a one-section hydrogenation product; b, enabling the one-section hydrogenation product in step a to contact a two-section hydrogenation catalyst in a two-section hydrogenation reactor, and performing two-section hydrogenation reaction, so as to obtain the 1,4-butanediol. The method has the advantages that the reaction yield rate is high, the amount of byproducts is small, and the selectivity is good.
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Paragraph 0062-0070
(2018/03/24)
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- Method for preparing 1,4-butylene glycol
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The invention provides a method for preparing 1,4-butylene glycol. The method is characterized in that 1,4-butynediol, an amorphous state nickel alloy catalyst and a copper alloy catalyst are in contact and are subjected to hydrogenation reaction; 1,4-butylene glycol products are collected. Compared with the prior art, the method has the advantages that the conversion rate of the 1,4-butynediol ishigh; the selectivity of the 1,4-butylene glycol is good; the product and a catalyst system can be easily separated; the product purity is good, and the like. The catalytic activity of a catalyst isgood; the efficiency is high; the service life is long; the catalyst can be recovered and used; the product cost is low.
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Paragraph 0041; 0044-0046; 0049-0051; 0054-0056; 0061-0074
(2018/03/24)
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- METHOD FOR PRODUCING TETRAHYDROFURANE, 1,4-BUTANEDIOL OR GAMMA-BUTYROLACTONE
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Processes for preparing tetrahydrofuran and/or butane-1,4-diol and/or gamma-butyrolactone are provided, including a process for preparing tetrahydrofuran (THF) from succinic acid that has been obtained by conversion of biomass, by conversion of the succinic acid to succinic anhydride, and hydrogenation of the succinic anhydride, with removal of certain secondary components.
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Paragraph 0118; 0119
(2018/02/03)
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- One-pot catalytic selective synthesis of 1,4-butanediol from 1,4-anhydroerythritol and hydrogen
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A physical mixture of ReOx-Au/CeO2 and carbon-supported rhenium catalysts effectively converted 1,4-anhydroerythritol to 1,4-butanediol with H2 as a reductant. The combination of these two catalysts in a one-pot reaction dramatically increased the selectivity of 1,4-butanediol as well as the conversion of 1,4-anhydroerythritol. The yield of 1,4-butanediol reached ~90%, which is the highest yield from erythritol and 1,4-anhydroerythritol so far, furthermore, at a relatively low reaction temperature of 413 K. This reaction involves the ReOx-Au/CeO2-catalyzed deoxydehydration of 1,4-anhydroerythritol to 2,5-dihydrofuran and ReOx/C-catalyzed successive isomerization, hydration and reduction reactions of 2,5-dihydrofuran.
- Wang, Tianmiao,Liu, Sibao,Tamura, Masazumi,Nakagawa, Yoshinao,Hiyoshi, Norihito,Tomishige, Keiichi
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supporting information
p. 2547 - 2557
(2018/06/18)
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- Selective Hydrogenation of Cyclic Imides to Diols and Amines and Its Application in the Development of a Liquid Organic Hydrogen Carrier
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Direct hydrogenation of a broad variety of cyclic imides to diols and amines using a ruthenium catalyst is reported here. We have applied this strategy toward the development of a new liquid organic hydrogen carrier system based on the hydrogenation of bis-cyclic imide that is formed by the dehydrogenative coupling of 1,4-butanediol and ethylenediamine using a new ruthenium catalyst. The rechargeable system has a maximum gravimetric hydrogen storage capacity of 6.66 wt%.
- Kumar, Amit,Janes, Trevor,Espinosa-Jalapa, Noel Angel,Milstein, David
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supporting information
p. 7453 - 7457
(2018/06/08)
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- Bipyridine ligand ruthenium complex is carried and its preparation method and application (by machine translation)
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The invention relates to a novel bipyridine is carried ligand ruthenium complex and its preparation method and in the ester compound hydrogenation is the application of the alcohol compound in the reaction. The use of the bipyridine ligand ruthenium complex catalytic hydrogenation is carried ester compound alcohol compound method is characterized in that: in order to ester compound material in an amount of 0.001 - 0.3 μM % bipyridyl is carried ligand ruthenium complex as catalyst, adding esters compound material in an amount of 1 - 10mol % alkali, in the 25 - 100 °C and 1 - 10MPa hydrogen pressure catalytic hydrogenation under the conditions of ester compound corresponding alcohol compound. The invention of the bipyridine ligand ruthenium complex is carried is convenient to prepare, stable structure, in the ester compound in hydrogenation reaction exhibits excellent catalytic activity. This invention has overcome the ester compound or a non-homogeneous phase catalytic hydrogenation system requires high-temperature high-pressure reaction conditions and high defects of the catalyst amount, catalyst consumption is small, mild reaction conditions, the reaction selectivity is good, improves the economy and the safety of the production system. (by machine translation)
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Paragraph 0098; 0099; 0100; 0101; 0104
(2017/04/28)
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- A using a supported metal catalyst method for preparing alcohols (by machine translation)
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The invention provides a method for using a supported metal catalyst for producing alcohol, comprising the following steps: carbonyl-containing compounds in the supported metal catalyst under the catalytic action of, and H2 To carry out the reduction reaction, to obtain the alcohol compound; the supported metal catalyst includes: catalyst carrier, loaded on the catalyst carrier and the metal; the metal for the 8th group metal in one or more of; the catalyst carrier is zirconium oxide, lanthanide metal oxide, lanthanide metal oxide-modified zirconia, 4th cycle transition metal oxide modified zirconia, 5th cycle transition metal oxide modified zirconia, alkaline earth metal oxide modified zirconium oxide or aluminum oxide modified zirconia. This invention adopts the above-mentioned particular catalyst for producing alcohol, has high conversion rate, good selectivity, mild reaction conditions, simple device and the like, it has good industrial application prospect. (by machine translation)
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Paragraph 0056-0061
(2017/09/01)
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- RUTHENIUM COMPLEX, METHOD FOR PRODUCING SAME, AND USE OF SAME
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The present invention provides a novel ruthenium complex that is easy to produce and handle and that can be supplied relatively inexpensively, a method for producing this ruthenium complex, a method for producing alcohols and the like using this ruthenium complex as a catalyst, a method for producing carbonyl compounds using this ruthenium complex as a catalyst, and a method for producing N-alkylamine compounds using this ruthenium complex as a catalyst. The present invention pertains to a ruthenium complex represented by general formula (1) RuX1X2(PNP) (NHC)m(Solv)n(1) (in general formula (1), X1 and X2 each independently represent a monovalent anionic monodentate ligand; PNP represents a tridentate aminodiphosphine ligand, NHC represents an N-heterocyclic carbene derived from a nitrogen-containing heterocyclic ring, and Solv represents a coordinating solvent; and m represents an integer from 1 to 3, n represents an integer from 0 to 2, and 1≦m+n≦3.), a method for producing the same, a catalyst including the same, and methods for producing various organic compounds using this catalyst.
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Paragraph 0353
(2017/04/11)
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- Synergetic Catalysis of Bimetallic CuCo Nanocomposites for Selective Hydrogenation of Bioderived Esters
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Bimetallic catalysts based on nonprecious transition metals have attracted increasing attention because of their unique synergistic effects in catalytic reactions, but the understanding of the nature of synergistic effects and their roles in a specific hydrogenation reaction remains lacking. Herein, a series of bimetallic CuxCoy/Al2O3 (x/y = 5:1, 2:1, 1:1, 1:2, 1:5) nanocomposite catalysts were fabricated via the successive calcination and reductive activation process of layered double hydroxide precursors. Their catalytic performance in the selective hydrogenation of bioderived ethyl levulinate to 1,4-pentanediol (1,4-PeD) depended sensitively on the chemical composition of bimetallic CuCo catalysts. The optimal bimetallic Cu2Co1/Al2O3 catalyst exhibited markedly improved catalytic activity and selectivity compared to monometallic Cu/Al2O3, as confirmed by its lower apparent activation energy barrier of 65.1 kJ mol-1 of the rate-determining step and its high selectivity of 93% to 1,4-PeD. Detailed characterization analyses and intrinsic catalytic studies revealed that the presence of CoOx species in the bimetallic CuxCoy/Al2O3 catalysts enhanced the metallic Cu dispersion and H2 activation ability. More importantly, the strong electronic interaction at the interface of Cu and adjacent CoOx species modified the chemical states of Cu species to create proper surface Cu0/Cu+ distributions and, particularly, provided synergic catalysis sites of Cu and electron-deficient CoOx species, which was primarily responsible for the excellent catalytic performance of bimetallic CuCo catalysts. The bimetallic CuCo catalysts exhibited good stability in both batch and fixed-bed continuous flow reactions. Furthermore, present CuCo nanocomposite catalyst could be applied to the highly selective hydrogenation of other carboxylic esters and lactones to synthesize valuable C4, C5, and C6 diols.
- Wu, Jun,Gao, Guang,Sun, Peng,Long, Xiangdong,Li, Fuwei
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p. 7890 - 7901
(2017/11/10)
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- PROCESS FOR THE PRODUCTION OF 1,4-BUTANEDIOL AND TETRAHYDROFURAN FROM FURAN
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The present invention provides a process for the production of 1,4-BDO and THF from furan, said process comprising : (i) contacting furan with hydrogen and water in a reactor in the presence of a catalytic composition, wherein the furan and water are contacted in the presence of a solvent, said solvent being selected from one or more of THF, 1,4-BDO and NBA, and converting at least a portion of said furan to 1,4-BDO and THF; (ii) producing a reactor product stream comprising gases, water, THF, 1,4-BDO and furan; (iii) separating gases from the reactor product stream; (iv) then separating at least a portion of each of the THF and 1,4-BDO from said reactor product stream; and (v) recycling the remainder of the reactor product stream, comprising water, optionally furan, and at least one of THF, 1,4-BDO and NBA, to the reactor.
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Page/Page column 12; 13
(2017/03/28)
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- PROCESS FOR THE PRODUCTION OF 1,4-BUTANEDIOL AND TETRAHYDROFURAN FROM FURAN
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The present invention provides a method for increasing the molar ratio of tetrahydrofuran to 1,4-butanediol in a process for the production of 1,4-butanediol and tetrahydrofuran, said process comprising contacting furan with hydrogen and water in a reactor vessel at an initial partial pressure of hydrogen, and in the presence of a catalytic composition comprising at least one metal on a solid support, wherein the at least one metal is selected from cobalt, nickel, ruthenium, palladium and platinum and wherein the molar ratio of tetrahydrofuran to 1,4-butanediol is increased by increasing the partial pressure of hydrogen in the reactor vessel above the initial partial pressure of hydrogen.
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Page/Page column 16-17
(2017/01/23)
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- CATALYTIC HYDROGENATION PROCESS FOR THE SYNTHESIS OF TERMINAL DIOLS FROM TERMINAL DIALKYL ALIPHATIC ESTERS
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A phosphorus ligand-free, mild, efficient and complete catalytic hydrogenation process is for the sustainable production of terminal diols from renewable terminal dialkyl esters with improved yield. Soluble, phosphorus ligand free Ru (II)-pincer type complexes can be used as catalysts in the hydrogenation process.
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Paragraph 0067; 0068; 0069
(2018/01/09)
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