- Polymer producing palladium complexes of unidentate phosphines in the methoxycarbonylation of ethene
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A wide range of unidentate phosphines have been studied as ligands for the palladium-catalysed methoxycarbonylation of ethene in the presence of methanesulfonic acid using methanol as the solvent. At high phosphine to Pd ratios, methyl propanoate is forme
- Smith, Graeme,Vautravers, Nicolas R.,Cole-Hamilton, David J.
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- One-pot, three-component synthesis of open-chain, polyfunctional sulfones
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Silyl enol ethers of esters, ketones, as well as allylstannane and allylsilanes react with sulfur dioxide activated with t-BuMe2SiOSO2CF3 to give silyl sulfinates that can be reacted in the same pot with a variety of electrophiles generating the corresponding polyfunctional sulfones. The silyl sulfinate intermediates are formed via ene-reactions following probably concerted mechanisms.
- Bouchez, Laure,Vogel, Pierre
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- Synthesis, characterization and catalytic properties of sulfonic acid functionalized magnetic-poly(divinylbenzene-4-vinylpyridine) for esterification of propionic acid with methanol
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The magnetic-poly(divinylbenzene-4-vinylpyridine) [m-poly(DVB-4VP)] microbeads (average diameter: 180-212 μm) were synthesized by copolymerizing of divinylbenzene (DVB) with 4-vinylpyridine (4VP) and by mixing this copolymer with Fe3O4 nanoparticles. The resultant material was characterized by N2 adsorption/desorption, ESR, elemental analysis, scanning electron microscope (SEM) and swelling studies. After functionalized with sulfonic acid, m-poly(DVB-4VP-SO3H) was characterized by FT-IR and TGA analysis. The results showed that both of Fe3O4 and -SO3H are bonded to the polymer successfully. N2 adsorption/desorption isotherms of synthesized samples had the hysteresis behaviour associated with mesoporous materials (pore diameter: 3.73 nm). Sulfonic acid functionalized mesoporous m-poly(DVB-4VP-SO3H) has been demonstrated to have higher reactivity than commercially available solid acid catalysts for the conversion of propionic acid to methyl ester. The apparent activation energy was found to be 38.5 kJ mol-1 for m-poly(DVB-4VP-20%SO3H). The catalyst showed negligible loss of activity after four repetitive cycles.
- Kara, Ali,Erdem, Beyhan
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- Sulfonic acid functionalized poly (ethylene glycol dimethacrylate-1-vinyl- 1,2,4-triazole) as an efficient catalyst for the synthesis of methyl propionate
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Sulfonic acid functionalized poly (ethylene glycol dimethacrylate-1-vinyl- 1,2,4-triazole), poly (EGDMA-VTAZ-SO3H) (average diameter 1.0-1.5 mm), was found to be efficient solid acid catalyst for the esterification of methanol and propionic acid under heterogeneous reaction conditions. The pristine polymer, poly (EGDMA-VTAZ), was produced by suspension polymerization and then proton-conducting polymer was obtained by blending of poly (EGDMA-VTAZ) with different percentage of H2SO4 solutions. The protonation of aromatic heterocyclic rings was proved with Fourier-transform infrared spectroscopy (FT-IR). Thermo gravimetric (TG) analysis showed that the catalyst is thermally stable up to 573 K. The surface morphology of the catalyst was characterized by scanning electron microscopy (SEM). Poly (EGDMA-VTAZ-SO3H) beads can be regenerated and reused, so this provides a potential application. It has a rate constant which exceeds that of Amberlyst-15 by a factor of about four at 333 K. As for the reaction equilibrium constant (Ke), which is independent of temperature ranging from 318 to 343 K, was determined to be 3.16. The apparent activation energy was found to be 41.6 kJ mol-1 for poly (EGDMA-VTAZ-SO3H).
- Erdem, Beyhan,Kara, Ali
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- Direct Hydroesterification of Ethylene with Methyl Formate with the New System RuCl3-NR4I-NR3: an Example of Catalytic Activation of the CH Bond of Methyl Formate?
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Upon using the simple RuCl3-NR4I-NR3 catalytic combination and dimethylformamide as solvent, an exceptionally reactive system is obtained for direct hydroesterification of ethylene with methyl formate (turnover frequency up to 2000 h-1) in the absence of carbon monoxide.
- Legrand, Christophe,Castanet, Yves,Mortreux, Andre,Petit, Francis
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- Highly Selective Continuous Gas-Phase Methoxycarbonylation of Ethylene with Supported Ionic Liquid Phase (SILP) Catalysts
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Supported ionic liquid phase (SILP) technology was applied for the first time to the Pd-catalyzed continuous, gas-phase methoxycarbonylation of ethylene to selectively produce methyl propanoate (MP) in high yields. The influence of catalyst and reaction p
- Khokarale, Santosh G.,García-Suárez, Eduardo J.,Fehrmann, Rasmus,Riisager, Anders
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- Zwitterion enhanced performance in palladium-phosphine catalyzed ethylene methoxycarbonylation
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Zwitterions were used for the first time as promoters in ethylene methoxycarbonylation for the production of methyl propionate. They were found to improve the catalytic performance of the Pd-phosphine system. The presence of zwitterions could contribute to stabilize transition states and active catalytic Pd intermediates. The beneficial effect of the zwitterions was found to be most pronounced, when low amount of a strong acid (MeSO3H) was used with respect to palladium (below 2 equiv.). Under these conditions, phosphine ligand alkylation and reaction vessel corrosion are also anticipated to be less severe.
- Khokarale,García-Suárez,Xiong,Mentzel,Fehrmann,Riisager
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- Ethene hydromethoxycarbonylation catalyzed by cis-[Pd(SO 4)(PPh3)2]/H2SO4/PPh 3
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The neutral precursor cis-[Pd(SO4)(PPh3)2] turns into an active catalyst for the hydromethoxycarbonylation of ethene when used in combination with H2SO4 and PPh3. The influence of the following operating conditions on the catalytic activity have been studied: (i) H2SO4/Pd ratio; (ii) PPh3/Pd ratio; (iii) total pressure with CO/ethene = 1/1; (iv) pressure of one gas at constant pressure of the other; (v) H2O concentration; (vi) temperature. At 100 °C a TOF = 2168 h-1 has been achieved when the catalytic system is used in the ratios Pd/H2SO4/P = 1/107/18 (mol/mol), under 6 bar (CO/E = 1/1), H2O concentration 0.16% in MeOH by weight. After catalysis and upon addition of LiCl, trans-[Pd(COEt)Cl(PPh3)2], which is related to the Pd-H catalytic cycle, has been isolated. Cis-[Pd(SO 4)(PPh3)2] in CD2Cl2/MeOH reacts with CO to give a PdCOOMe complex (related to the carbomethoxy mechanism ), which neither inserts ethene, nor gives methyl propanoate (MP). In the presence of H2O and H2SO4 the carbomethoxy complex is unstable giving a Pd-H complex, which yields catalysis to MP in the presence of CO and ethene. The Pd-H and Pd-COOMe catalytic cycles are discussed on the basis of the influence of the operating conditions on the TOF and of NMR evidences.
- Cavinato, Gianni,Facchetti, Sarah,Toniolo, Luigi
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- Acid-Promoter-Free Ethylene Methoxycarbonylation over Ru-Clusters/Ceria: The Catalysis of Interfacial Lewis Acid-Base Pair
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The interface of metal-oxide plays pivotal roles in catalytic reactions, but its catalytic function is still not clear. In this study, we report the high activity of nanostructured Ru/ceria (Ru-clusters/ceria) in the ethylene methoxycarbonylation (EMC) re
- An, Jinghua,Wang, Yehong,Lu, Jianmin,Zhang, Jian,Zhang, Zhixin,Xu, Shutao,Liu, Xiaoyan,Zhang, Tao,Gocyla, Martin,Heggen, Marc,Dunin-Borkowski, Rafal E.,Fornasiero, Paolo,Wang, Feng
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- Borate esters as alternative acid promoters in the palladium-catalyzed methoxycarbonylation of ethylene
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(Chemical Equation Presented) Out with convention! The use of borosalicylic acid, derived from boric and salicylic acids, as the acid promoter in the methoxycarbonylation of ethylene to give methyl propionate has been investigated (see scheme). Not only w
- Ferreira, Alta C.,Crous, Renier,Bennie, Linette,Meij, Anna M. M.,Blann, Kevin,Bezuidenhoudt, Barend C. B.,Young, Desmond A.,Green, Mike J.,Roodt, Andreas
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- Magnetically-separable Fe3O4@SiO2@SO4-ZrO2 core-shell nanoparticle catalysts for propanoic acid esterification
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Monodispersed, sulfated zirconia encapsulated magnetite nanoparticles were synthesized as magnetically-separable solid acid catalysts. Catalyst nanoparticles are prepared via coating preformed 80 nm Fe2O3 particles with a 15 nm SiO2 protective coating prior to growth of a uniform 28 nm ZrO2 shell. The thickness of the ZrO2 shell in resulting Fe3O4@SiO2@ZrO2 nanoparticles was controlled by adjusting the zirconium butoxide to Lutensol AO5 ratio, with 1:10 found as the optimal ratio to produce monodispersed ZrO2 coated nano-spheres. Sulfation using an ammonium sulfate precursor is less corrosive towards the core-shell structure of Fe3O4@SiO2@ZrO2 nanoparticles leading to superior sulfated materials compared to those obtained using H2SO4. Resulting Fe3O4@SiO2@SO4-ZrO2 solid acid catalysts exhibit high activity for propanoic acid esterification with methanol, far exceeding that of conventional sulfated zirconia nanoparticles, while being amenable to facile magnetic separation.
- Tai, Zhijun,Isaacs, Mark A.,Durndell, Lee J.,Parlett, Christopher M.A.,Lee, Adam F.,Wilson, Karen
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- TRANSITION METAL CATALYSED INTERACTION OF ETHYLENE AND ALKYL FORMATES
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Methyl propionate may be obtained by the homogeneous ruthenium catalysed interaction of ethylene and methyl formate.Product formation probably involves an initial fragmentation of the formate to free or ligand CO.
- Isnard, P.,Denise, B.,Sneeden, R. P. A.,Cognion, J. M.,Durual, P.
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- Homolytic Bond Strength and Radical Generation from (1-Carbomethoxyethyl)pentacarbonylmanganese(I)
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Compound (1-carbomethoxyethyl)pentacarbonylmanganese(I), [MnR(CO)5] (R = CHMeCOOMe, 1), was synthesized from K+[Mn(CO)5]– and methyl 2-bromopropionate and isolated in pure form. Upon thermal activation, the Mn–R bond is homolytically cleaved and the resulting 1-carbomethoxyethyl radical is able to initiate the polymerization of methyl acrylate (MA). A kinetic study of the decomposition of 1 in the presence of tris(trimethylsilyl)silane, TTMSS (10 equiv., saturation conditions) at 70, 65 and 60 °C yielded the T-dependent activation rate constant, ka, which allowed the calculation of the activation enthalpy (ΔH? = 35.3 ± 2.8 kcal mol–1) and entropy (ΔS? = 27.2 ± 8.1 cal mol–1 K–1) through the use of the Eyring relationship. The ΔH? value can be taken as an upper limit for the thermodynamic bond dissociation enthalpy, which was estimated as 36.9 kcal mol–1 by DFT calculations. The higher thermal stability of 1 relative to that of simpler R derivatives that form stronger Mn–R bonds can be attributed to more difficult CO dissociation, precluding the decomposition by β-H elimination.
- Morales-Cerrada, Roberto,Fliedel, Christophe,Gayet, Florence,Ladmiral, Vincent,Améduri, Bruno,Poli, Rinaldo
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- Effective recovery of acetic acid from wood vinegar by reactive distillation using tungstophosphoric acid-active carbon catalyst
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The recovery of acetic acid from wood vinegar by reactive distillation using tungstophosphoric acid-active carbon as catalyst has been studied. Methyl acetate is obtained as esterification product at the top of column. The loading capacity of tungstophosphoric acid on active carbon was optimized using batch distillation. In addition, the influence of various factors such as feed flow rate, MeOH vapor rate, rectifying section height and reflux ratio, on the conversion rate of acetic acid were investigated by using a model solution. A 71.94% recovery of acetic acid is obtained from wood vinegar under the following optimal conditions: loading capacity 33%, feed flow rate 60 g/h, MeOH vapor rate 114 g/h, rectifying section height 250 mm and reflux ratio 9:1.
- Li, Shuangming,Yang, Xuejiao,Chen, Jiaxiang,Wang, Xiujuan,Li, Wenxiu,Yu, Sansan
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- High-Performance RuCl3 Catalyst Systems for Hydro-Esterification of Methyl Formate and Ethylene
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RuCl3 catalyst system has many advantages for the hydro-esterification of methyl formate and ethylene to methyl propionate. However, the unsatisfied performance restricts the development of this route. In this work, high-performance RuCl3 catalyst systems (RuCl3-[PPN]Cl-Et4NI and RuCl3-NaI) are firstly reported for this reaction. In RuCl3-[PPN]Cl-Et4NI catalyst system, the conversion of methyl formate and the selectivity to methyl propionate are 93.9% and 90.9% at mild reaction conditions (165°C, 2.5 MPa), respectively. Noticeably, a simple inorganic RuCl3-NaI catalyst system achieves 88.8% conversion of methyl formate and 97.6% selectivity to methyl propionate (86.7% yield) at same conditions. NaI, as a promoter, may inhibit the decomposition of methyl formate and be conducive to the formation of methyl propionate. The effects of solvents and promoters are investigated in detail. In addition, the reaction mechanism has been also analyzed. It is hoped to lay a certain foundation for further industrial application.
- Li, Yan-Ru,Xu, Zhong-Ning,Bai, Bing,Wang, Zhi-Qiao,Guo, Guo-Cong
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- Method for synthesizing ester through catalytic esterification of ionic liquid
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The invention relates to a method for synthesizing ester through catalytic esterification of ionic liquid. The method comprises the following step: carrying out an esterification reaction on carboxylic acid and an organic matter containing a hydroxyl group under the catalysis of the ionic liquid to obtain an esterification product, wherein the general formula of the ionic liquid is [Bu3PR]N(CF3SO2)2, and R is a C8-C16 straight chain or branched chain alkyl group. According to the above technical scheme, the method for synthesizing the ester through catalytic esterification of the ionic liquid is high in catalyst catalytic activity, high in reaction selectivity, few in by-products, high in reaction rate and high in catalyst recycling performance.
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Paragraph 0028-0030; 0035-0039
(2021/06/22)
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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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- Light-Responsive, Reversible Emulsification and Demulsification of Oil-in-Water Pickering Emulsions for Catalysis
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Pickering emulsions are an excellent platform for interfacial catalysis. However, developing simple and efficient strategies to achieve product separation and catalyst and emulsifier recovery is still a challenge. Herein, we report the reversible transition between emulsification and demulsification of a light-responsive Pickering emulsion, triggered by alternating between UV and visible light irradiation. The Pickering emulsion is fabricated from Pd-supported silica nanoparticles, azobenzene ionic liquid surfactant, n-octane, and water. This phase behavior is attributed to the adsorption of azobenzene ionic liquid surfactant on the surface of the nanoparticles and the light-responsive activity of ionic liquid surfactant. The Pickering emulsion can be used as a microreactor that enables catalytic reaction, product separation as well as emulsifier and catalyst recycling. Catalytic hydrogenation of unsaturated hydrocarbons at room temperature and atmospheric pressure has been performed in this system to demonstrate product separation and emulsifier and catalyst re-use.
- Li, Zhiyong,Shi, Yunlei,Zhu, Anlian,Zhao, Yuling,Wang, Huiyong,Binks, Bernard P.,Wang, Jianji
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supporting information
p. 3928 - 3933
(2020/12/18)
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- Manganese-Mediated C-C Bond Formation: Alkoxycarbonylation of Organoboranes
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Alkoxycarbonylations are important and versatile reactions that result in the formation of a new C-C bond. Herein, we report on a new and halide-free alkoxycarbonylation reaction that does not require the application of an external carbon monoxide atmosphere. Instead, manganese carbonyl complexes and organo(alkoxy)borate salts react to form an ester product containing the target C-C bond. The required organo(alkoxy)borate salts are conveniently generated from the stoichiometric reaction of an organoborane and an alkoxide salt and can be telescoped without purification. The protocol leads to the formation of both aromatic and aliphatic esters and gives complete control over the ester's substitution (e.g., OMe, OtBu, OPh). A reaction mechanism was proposed on the basis of stoichiometric reactivity studies, spectroscopy, and DFT calculations. The new chemistry is particularly relevant for the field of Mn(I) catalysis and clearly points to a potential pathway toward irreversible catalyst deactivation.
- Van Putten, Robbert,Filonenko, Georgy A.,Krieger, Annika M.,Lutz, Martin,Pidko, Evgeny A.
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supporting information
p. 674 - 681
(2021/04/02)
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- Iron-catalysed 1,2-aryl migration of tertiary azides
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1,2-Aryl migration of α,α-diaryl tertiary azides was achieved by using the catalytic system of FeCl2/N-heterocyclic carbene (NHC) SIPr·HCl. The reaction generated aniline products in good yields after one-pot reduction of the migration-resultant imines.
- Wei, Kaijie,Yang, Tonghao,Chen, Qing,Liang, Siyu,Yu, Wei
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supporting information
p. 11685 - 11688
(2020/10/19)
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- Method for preparing organic carboxylic ester through combined catalysis of aryl bidentate phosphine ligand
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The invention discloses a method for preparing organic carboxylic ester by combined catalysis of an aryl bidentate phosphine ligand. The method comprises the following steps: under the action of a palladium compound/aryl bidentate phosphine ligand/acidic additive combined catalyst, carrying out a hydrogen esterification reaction on terminal olefin, carbon monoxide and alcohol so as to generate theorganic carboxylic ester with one more carbon than olefin. According to the invention, by adoption of the palladium compound/aryl bidentate phosphine ligand/acidic additive combined catalyst, good catalytic activity and selectivity for the hydrogen esterification reaction of the olefin are achieved, and olefin carbonylation to synthesize organic carboxylic ester can be efficiently catalyzed. Thearyl bidentate phosphine ligand has a rigid skeleton structure of a rigid ligand and the flexibility of a flexible ligand, so the aryl bidentate phosphine ligand has proper flexibility due to the characteristic that the aryl bidentate phosphine ligand is soft and rigid, and a most favorable coordination mode and a stable active structure in space are favorably formed. In addition, the aryl bidentate phosphine ligand has the advantages of high stability, simple and convenient synthesis method and the like; and a novel industrial technology is provided for production of organic carboxylate compounds.
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Paragraph 0020-0035
(2020/05/29)
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- Base-free transfer hydrogenation of aryl-ketones, alkyl-ketones and alkenones catalyzed by an IrIIICp* complex bearing a triazenide ligand functionalized with pyrazole
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An IrIIICp* complex (2) bearing a triazenide ligand functionalized with pyrazole was synthesized and fully characterized by spectroscopic methods and the structure confirmed by X-ray diffraction studies. The catalytic activity of 2 and the control complex 3, which lacks of pyrazole in its structure, was evaluated in the reduction of aryl-ketones, alkyl-ketones, α,β-unsaturated and γ,δ-unsaturated ketones. The catalytic system, using either 2 or 3, exhibited good to excellent selectivity when tested with ketones and alkenones at 90 °C in 2-propanol as hydrogen source under base-free conditions. Reactivity of 2 in 2-propanol and NaH gave a neutral metal hydride (4) while in the absence of base gave two major cationic hydrides species (5 and 6).
- Medrano-Castillo, Layla J.,Collazo-Flores, Miguel á.,Camarena-Díaz, Juan P.,Correa-Ayala, Erick,Chávez, Daniel,Grotjahn, Douglas B.,Rheingold, Arnold L.,Miranda-Soto, Valentín,Parra-Hake, Miguel
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- PRODUCTION OF ALKYL ESTERS OF ACRYLIC ACID
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A process for producing a mixture including acrylic acid or derivatives thereof, the process including the step of contacting a mixture of lactic acid or derivatives thereof and a solvent over a dehydration catalyst to produce the mixture including alkyl esters of acrylic acid, wherein the density of the solvent ranges from about 10 to about 500 kg/m3 under operating conditions.
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Page/Page column 7-8
(2020/01/31)
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- Efficient and catalyst free synthesis of acrylic plastic precursors: Methyl propionate and methyl methacrylate synthesis through reversible CO2 capture
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Methyl propionate (MP) and methyl methacrylate (MMA) are considered as industrially important precursors for large-scale acrylic plastic production. The existing industrial synthetic protocols for these precursors utilize expensive catalysts accompanied by toxic and explosive gases such as carbon monoxide, ethylene and hydrogen. Herein, we for the first time report highly selective, catalyst-free and room temperature synthesis of MP and MMA precursors through a reversible CO2 capture approach involving an organic superbase. In short, initially an equimolar mixture of an organic superbase 1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU) and methanol was reversibly reacted with molecular CO2 and the obtained switchable ionic liquid, [DBUH][MeCO3], further reacted with an equivalent amount of propionic anhydride or methacrylic anhydride to form MP or MMA, respectively. These reactions were accomplished in different solvents such as DMSO and methanol, and in the case of methanol, separation of reaction products occurs from in situ formed DBU derivatives such as [DBU][propionate] or [DBU][methacrylate]. In the case of both MP and MMA syntheses, after the use of methanol as a solvent, good recovery of the alcoholic solution of esters was achieved where 85% and 92% yields of MP and MMA were obtained, respectively. Molecular DBU was recovered from its propionate and methacrylate salts using NaCl saturated alkaline solution. Furthermore, the recovered MMA with methanol was polymerised to poly-MMA using a benzoyl peroxide induced free radical polymerisation process. The synthesis and separation of MP or MMA and the recovery of DBU were monitored by NMR analysis. Hence, unlike DMSO, methanol not only functioned as a reagent in CO2 capture and as a solvent medium in MP, MMA and poly-MMA syntheses but also assisted in the recovery of DBU from the reaction mixture. Most importantly, here we present a more efficient, safer and single solvent based alternative synthetic approach for the synthesis of acrylic plastic precursors MP or MMA compared to existing industrial methods. Also, no toxic or expensive catalysts were required.
- Khokarale, Santosh Govind,Mikkola, Jyri-Pekka
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p. 2138 - 2147
(2019/04/26)
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- Hydroformylation of unsaturated esters and 2,3-dihydrofuran under solventless conditions at room temperature catalysed by rhodium: N-pyrrolyl phosphine catalysts
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Rhodium complexes of the type HRh(CO)L3 (where L is an N-pyrrolyl phosphine, such as P(NC4H4)3, PPh(NC4H4)2, or PPh2(NC4H4)) were applied in the hydroformylation of less reactive unsaturated substrates, namely allyl acetate, butyl acrylate, methyl acrylate, 2,3-dihydrofuran and vinyl acetate. Even at room temperature, these catalysts enabled complete substrate conversion and high chemoselectivity towards the corresponding aldehydes. High conversion of vinyl acetate (88% in 6 h) to the branched aldehyde was obtained with HRh(CO)[P(NC4H4)3]3 at 25 °C. An increase of the turnover frequency, TOF, up to 2000 mol mol-1 h-1 was achieved in this reaction under 20 bar of syngas (H2/CO = 1) at 80 °C. The introduction of chiral phosphines, BINAP or Ph-BPE, to this system resulted in the production of a branched aldehyde with enantioselectivity, ee, up to 44 and 81%, respectively. High activity combined with high enantioselectivity was achieved due to the formation of the mixed rhodium hydrides HRh(CO)[P(NC4H4)3](BINAP) and HRh(CO)[P(NC4H4)3](Ph-BPE), identified by the NMR method.
- Alsalahi,Trzeciak
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p. 16990 - 16999
(2019/11/14)
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- Hyper-Cross-Linked Polyacetylene-Type Microporous Networks Decorated with Terminal Ethynyl Groups as Heterogeneous Acid Catalysts for Acetalization and Esterification Reactions
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Heterogeneous catalysts based on materials with permanent porosity are of great interest owing to their high specific surface area, easy separation, recovery, and recycling ability. Additionally, porous polymer catalysts (PPCs) allow us to tune catalytic activity by introducing various functional centres. This study reports the preparation of PPCs with a permanent micro/mesoporous texture and a specific surface area SBET of up to 1000 m2 g?1 active in acid-catalyzed reactions, namely aldehyde and ketone acetalization and carboxylic acid esterification. These PPC-type conjugated hyper-cross-linked polyarylacetylene networks were prepared by chain-growth homopolymerization of 1,4-diethynylbenzene, 1,3,5-triethynylbenzene and tetrakis(4-ethynylphenyl)methane. However, only some ethynyl groups of the monomers (from 58 to 80 %) were polymerized into the polyacetylene network segments while the other ethynyl groups remained unreacted. Depending on the number of ethynyl groups per monomer molecule and the covalent structure of the monomer, PPCs were decorated with unreacted ethynyl groups from 3.2 to 6.7 mmol g?1. The hydrogen atoms of the unreacted ethynyl groups served as acid catalytic centres of the aforementioned organic reactions. To the best of our knowledge, this is first study describing the high activity of hydrogen atoms of ethynyl groups in acid-catalyzed reactions.
- Sekerová, Lada,Lhotka, Miloslav,Vysko?ilová, Eli?ka,Faukner, Tomá?,Slováková, Eva,Brus, Ji?í,?erveny, Libor,Sedlá?ek, Jan
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p. 14742 - 14749
(2018/09/25)
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- Selective Hydrodeoxygenation of Alkyl Lactates to Alkyl Propionates with Fe-based Bimetallic Supported Catalysts
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Hydrodeoxygenation (HDO) of methyl lactate (ML) to methyl propionate (MP) was performed with various base-metal supported catalysts. A high yield of 77 % MP was obtained with bimetallic Fe–Ni/ZrO2 in methanol at 220 °C and 50 bar H2. A synergistic effect of Ni increased the yield of MP significantly when using Fe–Ni/ZrO2 instead of Fe/ZrO2 alone. Moreover, the ZrO2 support contributed to improve the yield as a phase transition of ZrO2 from tetragonal to monoclinic occurred after metal doping giving rise to fine dispersion of the Fe and Ni on the ZrO2, resulting in a higher catalytic activity of the material. Interestingly, it was observed that Fe–Ni/ZrO2 also effectively catalyzed methanol reforming to produce H2 in situ, followed by HDO of ML, yielding 60 % MP at 220 °C with 50 bar N2 instead of H2. Fe–Ni/ZrO2 also catalyzed HDO of other short-chain alkyl lactates to the corresponding alkyl propionates in high yields around 70 %. No loss of activity of Fe–Ni/ZrO2 occurred in five consecutive reaction runs demonstrating the high durability of the catalyst system.
- Khokarale, Santosh Govind,He, Jian,Schill, Leonhard,Yang, Song,Riisager, Anders,Saravanamurugan, Shunmugavel
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p. 681 - 687
(2018/02/13)
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- Methyl propionate preparation method
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The present invention relates to a methyl propionate preparation method, which comprises: mixing methanol and a ruthenium-supported metal oxide catalyst, placing the obtained mixture in a pressure container, filling with ethylene and carbon monoxide, sealing, and stirring, wherein the reaction temperature is more than or equal to 130 DEG C, the reaction time is more than or equal to 2 h, and the ruthenium-supported metal oxide catalyst is one or a plurality of material selected from Ru/TiO2, Ru/Nb2O5, Ru/CeO2 and Ru/Al2O3. According to the present invention, with the method, the catalyst is easily separated from the reaction system after the reaction, and can be used repeatedly, and the yield of propyl formate is up to 90%.
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Paragraph 0038; 0040; 0042; 0044; 0046; 0048; 0050; 0052
(2018/06/16)
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- Methyl propionate preparation method
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The invention relates to a methyl propionate preparation method, which comprises carrying out a reaction on raw materials including ethylene, carbon monoxide and methanol in a fixed bed reactor at a reaction temperature of 150-250 DEG C, wherein a reaction pipe is filled with a ruthenium-loaded metal oxide catalyst, and the reaction pipe with the catalyst is placed in the fixed bed reactor. According to the present invention, the reaction has the 100% atomic economy, does not produce by-products, and uses the noble metal-loaded metal oxide or the molecular sieve as the catalyst, wherein the catalyst is easily prepared and efficiently catalyzes the reaction, and the yield of methyl propionate can reach over 80% .
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Paragraph 0028; 0030; 0032; 0034; 0036; 0038; 0040; 0042
(2018/06/16)
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- PROCESS FOR THE ALKOXYCARBONYLATION OF ETHYLENICALLY UNSATURATED COMPOUNDS WITH MONOPHOSPHINE LIGANDS
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The invention relates to a process comprising the following process steps: a) introducing an ethylenically unsaturated compound;b) adding a monophosphine ligand and a compound which comprises Pd, or adding a complex comprising Pd and a monophosphine ligand;c) adding an aliphatic alcohol;d) supplying CO;e) heating the reaction mixture, the ethylenically unsaturated compound being reacted to form an ester; where the monophosphine ligand is a compound of formula (I) where R1 is selected from —(C1-C12)-alkyl, —O—(C1-C12)-alkyl, —O—(C6-C20)-aryl, —(C6-C20)-aryl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —(C3-C20)-heteroaryl;R2 is selected from —(C6-C20)-aryl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —(C3-C20)-heteroaryl;R3 is —(C3-C20)-heteroaryl;and R1, R2 and R3 may each independently be substituted by one or more substituents selected from—(C1-C12)-alkyl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —O—(C1-C12)-alkyl, —O—(C1-C12)-alkyl-(C6-C20)-aryl, —O—(C3-C12)-cycloalkyl, —S—(C1-C12)-alkyl, —S—(C3-C12)-cycloalkyl, —COO—(C1-C12)-alkyl, —COO—(C3-C12)-cycloalkyl, —CONH—(C1-C12)-alkyl, —CONH—(C3-C12)-cycloalkyl, —CO—(C1-C12)-alkyl, —CO—(C3-C12)-cycloalkyl, —N—[(C1-C12)-alkyl]2, —(C6-C20)-aryl, —(C6-C20)-aryl-(C1-C12)-alkyl, —(C6-C20)-aryl-O—(C1-C12)-alkyl, —(C3-C20)-heteroaryl, —(C3-C20)-heteroaryl-(C1-C12)-alkyl, —(C3-C20)-heteroaryl-O—(C1-C12)-alkyl, —COOH, —OH, —SO3H, —NH2, halogen.
- -
-
Paragraph 0158; 0159
(2018/02/28)
-
- Selective Base-free Transfer Hydrogenation of α,β-Unsaturated Carbonyl Compounds using iPrOH or EtOH as Hydrogen Source
-
Commercially available Ru-MACHOTM-BH is an active catalyst for the hydrogenation of several functional groups and for the dehydrogenation of alcohols. Herein, we report on the new application of this catalyst to the base-free transfer hydrogenation of carbonyl compounds. Ru-MACHOTM-BH proved to be highly active and selective in this transformation, even with α,β-unsaturated carbonyl compounds as substrates. The corresponding aliphatic, aromatic and allylic alcohols were obtained in excellent yields with catalyst loadings as low as 0.1–0.5 mol % at mild temperatures after very short reaction times. This protocol tolerates iPrOH and EtOH as hydrogen sources. Additionally, scale up to multi-gram amounts was performed without any loss of activity or selectivity. An outer-sphere mechanism has been proposed and the computed kinetics and thermodynamics of crotonaldehyde and 1-phenyl-but-2-en-one are in perfect agreement with the experiment.
- Farrar-Tobar, Ronald A.,Wei, Zhihong,Jiao, Haijun,Hinze, Sandra,de Vries, Johannes G.
-
supporting information
p. 2725 - 2734
(2018/02/28)
-
- Structural, electronic and catalytic properties of palladium nanoparticles supported on poly(ionic liquid)
-
The structural, electronic and support effect on palladium nanoparticles (Pd NPs) prepared by sputtering deposition and chemical reduction of a Pd(II) precursor in/on a poly(ionic liquid) (PIL) was investigated in the selective hydrogenation of α,β-unsaturated carbonyl compounds and dienes. Sputtering deposition generates naked NPs with a narrow size distribution (3.2–3.8 nm) that are predominantly composed of Pd(0) (85–100%). Conversely, chemical reduction produces PIL-covered NPs with almost twice the average size (6.6 nm) and only 15% Pd(0). Regard the catalytic performance, support composition (by ionic liquid (IL) addition or not) and NP location are decisive. The best activity and selectivity was obtained with imprinted Pd NPs on a PIL/IL mixture (D-MPIL.NTf2/IL-Pd catalyst). A kinetic investigation was conducted using 2-cyclohexen-1-one (CHN) and D-MPIL.NTf2/IL-Pd catalyst revealing that this reaction follows the Langmuir-Hinshelwood mechanism. Enthalpies obtaining from a Van't Hoff plot show that the adsorption of the CHN substrate on the surface of the PIL-Pd catalyst is an exothermic process (-9 kJ mol?1), whereas H2 adsorption occurs by an endothermic process (12 kJ mol?1). This distinct behavior is consistent with the rate determining step proposed, in which the independent adsorption of reagents is followed by the hydrogenation of a π-allyl intermediate on the catalyst surface.
- Simon, Nathália M.,Abarca, Gabriel,Scholten, Jackson D.,Domingos, Josiel B.,Mecerreyes, David,Dupont, Jairton
-
-
- Hydrogenation of Ketones and Esters Catalyzed by Pd/C?SiO2
-
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
-
p. 195 - 198
(2018/03/26)
-
- Methylation of Aliphatic and Aromatic Carboxylic Acids with Dimethyl Carbonate under the Influence of Manganese and Iron Carbonyls
-
The synthesis of methyl esters has been carried out via the reaction of aliphatic and aromatic carboxylic acids with dimethyl carbonate in the presence of manganese and iron carbonyls. The optimal ratio of catalyst and reagents and other conditions for the synthesis of methyl esters of carboxylic acids with high yield have been found.
- Khusnutdinov,Shchadneva,Mayakova, Yu. Yu.
-
-
- Impact of Macroporosity on Catalytic Upgrading of Fast Pyrolysis Bio-Oil by Esterification over Silica Sulfonic Acids
-
Fast pyrolysis bio-oils possess unfavorable physicochemical properties and poor stability, in large part, owing to the presence of carboxylic acids, which hinders their use as biofuels. Catalytic esterification offers an atom- and energy-efficient route to upgrade pyrolysis bio-oils. Propyl sulfonic acid (PrSO3H) silicas are active for carboxylic acid esterification but suffer mass-transport limitations for bulky substrates. The incorporation of macropores (200 nm) enhances the activity of mesoporous SBA-15 architectures (post-functionalized by hydrothermal saline-promoted grafting) for the esterification of linear carboxylic acids, with the magnitude of the turnover frequency (TOF) enhancement increasing with carboxylic acid chain length from 5 % (C3) to 110 % (C12). Macroporous–mesoporous PrSO3H/SBA-15 also provides a two-fold TOF enhancement over its mesoporous analogue for the esterification of a real, thermal fast-pyrolysis bio-oil derived from woodchips. The total acid number was reduced by 57 %, as determined by GC×GC–time-of-flight mass spectrometry (GC×GC–ToFMS), which indicated ester and ether formation accompanying the loss of acid, phenolic, aldehyde, and ketone components.
- Manayil, Jinesh C.,Osatiashtiani, Amin,Mendoza, Alvaro,Parlett, Christopher M.A.,Isaacs, Mark A.,Durndell, Lee J.,Michailof, Chrysoula,Heracleous, Eleni,Lappas, Angelos,Lee, Adam F.,Wilson, Karen
-
p. 3506 - 3511
(2017/09/15)
-
- Method for synthesizing ester through quaternary phosphonium salt ionic liquid catalyzed esterification
-
The invention discloses a method for synthesizing an ester through quaternary phosphonium salt ionic liquid catalyzed esterification. The method is characterized in that the esterification product is obtained through an esterification reaction of carboxylic acid and a hydroxyl group-containing organic matter under the catalysis of a quaternary phosphonium salt ion liquid, wherein the general formula of the quaternary phosphonium salt ion liquid is [Bu3PR]X, R is a C6-C16 linear or branched alkyl group, and X is a p-C7H7SO, CF3SO, HSO or H2PO. The method for synthesizing the ester through quaternary phosphonium salt ionic liquid catalyzed esterification has the advantages of high catalytic activity, high reaction selectivity, few byproducts, and high recycling performance of the catalyst.
- -
-
Paragraph 0073-0079; 0082-0085
(2017/08/31)
-
- Benzene-based diphosphine ligands for alkoxycarbonylation
-
The invention relates to benzene-based diphosphine ligands for alkoxycarbonylation. Specifically, the invention relates to compounds of formula (I), where m and n are each independently 0 or 1; R1, R2, R3, R4 are each independently selected from -(C1-C12)-alkyl, -(C3-C12)-cycloalkyl, -(C3-C12)-heterocycloalkyl, -(C6-C20)-aryl, -(C3-C20)-heteroaryl; at least one of the R1, R2, R3, R4 radicals is a -(C3-C20)-heteroaryl radical; and to the use thereof as ligands in alkoxycarbonylation.
- -
-
Paragraph 0156; 0157; 0158; 0178
(2017/02/28)
-
- Efficient Palladium-Catalyzed Alkoxycarbonylation of Bulk Industrial Olefins Using Ferrocenyl Phosphine Ligands
-
The development of ligands plays a key role and provides important innovations in homogeneous catalysis. In this context, we report a novel class of ferrocenyl phosphines for the alkoxycarbonylation of industrially important alkenes. A basic feature of our ligands is the combination of sterically hindered and amphoteric moieties on the P atoms, which leads to improved activity and productivity for alkoxycarbonylation reactions compared to the current industrial state-of-the-art ligand 1,2-bis((di-tert-butylphosphino)methyl)benzene). Advantageously, palladium catalysts with these novel ligands also enable such transformations without additional acid under milder reaction conditions. The practicability of the optimized ligand was demonstrated by preparation on >10 g scale and its use in palladium-catalyzed carbonylations on kilogram scale.
- Dong, Kaiwu,Sang, Rui,Fang, Xianjie,Franke, Robert,Spannenberg, Anke,Neumann, Helfried,Jackstell, Ralf,Beller, Matthias
-
supporting information
p. 5267 - 5271
(2017/04/27)
-
- MONOPHOSPHINE COMPOUNDS AND PALLADIUM CATALYSTS BASED THEREON FOR THE ALKOXYCARBONYLATION OF ETHYLENICALLY UNSATURATED COMPOUNDS
-
The invention relates to compounds of formula (I) where R1 is selected from —(C1-C12)-alkyl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl; R2 is selected from —(C3-C12)-heterocycloalkyl, —(C6-C20)-aryl, —(C3-C20)-heteroaryl; R3 is —(C3-C20)-heteroaryl; and R1, R2 and R3 may each independently be substituted by one or more substituents selected from —(C1-C12)-alkyl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —O—(C1-C12)-alkyl, —O—(C1-C12)-alkyl-(C6-C20)-aryl, —O—(C3-C12)-cycloalkyl, —S—(C1-C12)-alkyl, —S—(C3-C12)-cycloalkyl, —COO—(C1-C12)-alkyl, —COO—(C3-C12)-cycloalkyl, —CONH—(C1-C12)-alkyl, —CONH—(C3-C12)-cycloalkyl, —CO—(C1-C12)-alkyl, —COO—(C3-C12)-cycloalkyl, —N—[(C1-C12)-alkyl]2, —(C6-C20)-aryl, —(C6-C20)-aryl-(C1-C12)-alkyl, —(C6-C20)-aryl-O—(C1-C12)-alkyl, —(C3-C20)-heteroaryl, —(C3-C20)-heteroaryl-(C1-C12)-alkyl, —(C3-C20)-heteroaryl-O—(C1-C12)-alkyl, —COOH, —OH, —SO3H, —NH2, halogen. The invention further relates to Pd complexes comprising the compound according to the invention and to the use thereof in alkoxycarbonylation.
- -
-
Paragraph 0172; 0173; 0174; 0175
(2017/02/24)
-
- A CATALYST FOR THE CARBONYLATION OF ALKENES
-
The present application relates to a metal complex of Formula (I) and a catalyst composition for the carbonylation of alkenes comprising the metal complex, wherein the metal is a group 10 element such as palladium, platinum or nickel, and the complex comprises a bidentate phosphine ligand. The present invention also relates to a process for the preparation of a dicarboxylic acid or ester thereof from an alkenoic acid or ester thereof, or a process for the preparation of a carboxylic acid or ester thereof from an alkene or alkenoic acid with high selectivity and activity using said metal complex or catalyst composition. The present application also relates to a method of preparing Nylon 6-6 comprising the step of copolymerising adipic acid with hexamethylenediamine.
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-
Page/Page column 51
(2017/09/02)
-
- Catalyst system
-
The present invention provides a catalyst system capable of catalyzing the carbonylation of an ethylenically unsaturated compound, which system is obtainable by combining: a) a metal of Group VIB or Group VIIIB or a compound thereof,b) a bidentate phosphine, arsine or stibine ligand, andc) an acid, wherein the ligand is present in at least a 2:1 molar excess compared to the metal or the metal in the metal compound, and that the acid is present in at least a 2:1 molar excess compared to the ligand, a process for the carbonylation of an ethylenically unsaturated compound, a reaction medium, and use of the system.
- -
-
Page/Page column 53-60
(2017/11/17)
-
- Metal-Free Catalytic Reduction of α,β-Unsaturated Esters by 1,3,2-Diazaphospholene and Subsequent C-C Coupling with Nitriles
-
1,3,2-Diazaphospholene 1 catalyzes the conjugate transfer hydrogenation as well as the 1,4-hydroboration of α,β-unsaturated esters. The initial step for both processes involves a 1,4-hydrophosphination of the α,β-unsaturated esters to afford a phosphinyl enol ether. Subsequent cleavage of the P-O bond in the phosphinyl enol ether by ammonia-borane (AB) generates an enol intermediate which tautomerizes to saturated esters, while the P-O bond cleavage by HBpin via a formal σ-bond metathesis affords boryl enolate intermediate. The latter could undergo a further coupling reaction with nitriles to form substituted amino diesters or 1,3-imino esters, depending on α,β-unsaturated ester substrates. These catalytic reactions can also be performed in a one-pot manner, illustrating a protocol for metal-free catalytic C-C bond construction.
- Chong, Che Chang,Rao, Bin,Kinjo, Rei
-
p. 5814 - 5819
(2017/09/15)
-
- Engineering cyclohexanone monooxygenase for the production of methyl propanoate
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A previous study showed that cyclohexanone monooxygenase from Acinetobacter calcoaceticus (AcCHMO) catalyzes the Baeyer-Villiger oxidation of 2-butanone, yielding ethyl acetate and methyl propanoate as products. Methyl propanoate is of industrial interest as a precursor of acrylic plastic. Here, various residues near the substrate and NADP+ binding sites in AcCHMO were subjected to saturation mutagenesis to enhance both the activity on 2-butanone and the regioselectivity toward methyl propanoate. The resulting libraries were screened using whole cell biotransfor-mations, and headspace gas chromatography-mass spectrometry was used to identify improved AcCHMO variants. This revealed that the I491A AcCHMO mutant exhibits a significant improvement over the wild type enzyme in the desired regioselectivity using 2-butanone as a substrate (40% vs 26% methyl propanoate, respectively). Another interesting mutant is the T56S AcCHMO mutant, which exhibits a higher conversion yield (92%) and kcat (0.5 s-1) than wild type AcCHMO (52% and 0.3 s-1, respectively). Interestingly, the uncoupling rate for the T56S AcCHMO mutant is also significantly lower than that for the wild type enzyme. The T56S/I491A double mutant combined the beneficial effects of both mutations leading to higher conversion and improved regioselectivity. This study shows that even for a relatively small aliphatic substrate (2-butanone), catalytic efficiency and regioselectivity can be tuned by structure-inspired enzyme engineering.
- Van Beek, Hugo L.,Romero, Elvira,Fraaije, Marco W.
-
p. 291 - 299
(2018/02/02)
-
- Gas-Phase Reaction of Methyl n-Propyl Ether with OH, NO3, and Cl: Kinetics and Mechanism
-
Rate constants at room temperature (293 ± 2 K) and atmospheric pressure for the reaction of methyl n-propyl ether (MnPE), CH3OCH2CH2CH3, with OH and NO3 radicals and the Cl atom have been determined in a 100 L FEP-Teflon reaction chamber in conjunction with gas chromatography-flame ionization detector (GC-FID) as the detection technique. The obtained rate constants k (in units of cm3 molecule-1 s-1) are (9.91 ± 2.30) × 10-12, (1.67 ± 0.32) × 10-15, and (2.52 ± 0.14) × 10-10 for reactions with OH, NO3, and Cl, respectively. The products of these reactions were investigated by gas chromatography-mass spectrometry (GC-MS), and formation mechanisms are proposed for the observed reaction products. Atmospheric lifetimes of the studied ether, calculated from rate constants of the different reactions, reveal that the dominant loss process for MnPE is its reaction with OH, while in coastal areas and in the marine boundary layer, MnPE loss by Cl reaction is also important.
- Zhu, Jianqiang,Wang, Shuyan,Tsona, Narcisse T.,Jiang, Xiaotong,Wang, Yifeng,Ge, Maofa,Du, Lin
-
p. 6800 - 6809
(2017/09/23)
-
- Direct synthesis of isobutyraldehyde from methanol and ethanol on Cu-Mg/Ti-SBA-15 catalysts: The role of Ti
-
Herein, Cu-Mg/Ti-SBA-15 catalysts were prepared through the modification of Cu and Mg to mesoporous Ti-SBA-15 zeolites with different Ti/Si ratios and used for the synthesis of isobutyraldehyde (IBA) from methanol and ethanol. The catalysts were characterized via various techniques including XRF, XRD, TEM, N2 sorption, CO2-TPD, FT-IR, and XPS. With an increase in Ti content, CuO was well dispersed accordingly, and the amounts and strength of the basic sites were reduced. However, an excess introduction of Ti led to the accumulation of single TiO2 crystals, inducing a decrease in the surface area and a deviation from the regular pattern such that the binding energies of Cu 2p, Mg 2p, and Si 2p shifted to lower values. This precisely affected the catalytic behaviors of the prepared catalysts synergistically. The catalyst stability was improved with the increasing Ti content accordingly, and over the catalyst with a Ti/Si ratio = 4/15, the IBA selectivity, after 24 h reaction, could still reach 25%, which was the best durability ever reported for IBA synthesis from methanol and ethanol. The catalytic performance test conducted using a regenerated catalyst and IR measurement of the spent catalyst indicated that carbon deposition on the catalyst surface could be depressed to some extent with the increasing Ti content.
- Zhang, Junfeng,Zhang, Meng,Wang, Xiaoxing,Zhang, Qingde,Song, Faen,Tan, Yisheng,Han, Yizhuo
-
p. 9639 - 9648
(2017/09/18)
-
- Methylation of mono- and dicarboxylic acids with dimethyl carbonate catalyzed with binder-free zeolite NaY
-
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
-
p. 163 - 168
(2017/04/24)
-
- PROCESS FOR HYDROGENOLYSIS OF ALPHA-HYDROXY ESTERS OR ACIDS USING A HETEROGENEOUS CATALYST
-
The present invention relates to a method for hydrogenolysis of alpha-hydroxy esters or acids, comprising reacting the alpha-hydroxy ester or acid in the presence of a heterogeneous catalyst. The present invention also relates to a method for producing propionic acid ester, and the use of any of the methods for the production of propionic acid esters, such as alkyl propionate.
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-
Page/Page column 26; 27
(2017/01/31)
-
- Tandem and One-Pot Hydroformylation/Michael Reactions of Acrylates
-
The combination of various reactions in one operational step leads to many advantages in synthetic strategies, such as a lower consumption of resources, effort, and time, when intermittent workup and purification steps can be avoided. The hydroformylation reaction of acrylates gives access to 2-formylpropanoates, which thanks to their structural features constitute useful intermediates in the synthesis of more complex compounds. Herein, we report a simple and convenient one-pot strategy to synthesize functionalized carbonyl compounds starting from these readily available substrates, via tandem or one-pot hydroformylation, Michael addition, and aldol reactions.
- Quintero-Duque, Samuel,Fleischer, Ivana
-
p. 925 - 932
(2017/02/15)
-
- Mechanistic Investigations of Reactions of the Frustrated Lewis Pairs (Triarylphosphines/B(C6F5)3) with Michael Acceptors
-
Frustrated Lewis pair (FLP)-catalyzed reduction of Michael acceptors is a challenging reaction that proceeds with specific FLP structures. Kinetics and equilibrium of the reactions of two phosphines (Ar3P), namely tri(1-naphthyl)phosphine and tri(o-tolyl)phosphine, are reported with reference electrophiles. The reason for the failure of the FLPs (Ar3P/B(C6F5)3) to reduce activated alkenes under H2 pressure is shown to be a hydrophosphination process that inhibits the reduction reaction. Kinetic and thermodynamic factors controlling both pathways are discussed in light of Mayr's free linear energy relationships.
- Dupré, Jonathan,Gaumont, Annie-Claude,Lakhdar, Sami
-
supporting information
p. 694 - 697
(2017/02/10)
-
- Process for the preparation of propionic acid methyl ester
-
The invention relates to a preparation method of propionate, belonging to the technical field of preparation of organic substances. Propanoic acid and monobasic alcohol are subjected to esterification reaction under the action of a gel-type strong-acid ion exchange resin catalyst to generate the propionate. The gel-type strong-acid ion exchange resin is a hydrogen-type styrene-stilbene copolymer with sulfonate group, and the pore size of the resin is less than 8nm. The preparation method provided by the invention uses the catalyst to effectively adsorb the reaction impurities and enhance the product purity; and the catalyst has the advantages of favorable catalytic effect and low corrosivity, and can be easily separated from the product.
- -
-
Paragraph 0019; 0020; 0021; 0022; 0023; 0024
(2016/12/22)
-
- Synthesis, characterization and catalytic performance of a novel picolinic acid-12-molybdophosphoric acid hybrid catalyst
-
A novel 12-molybdophosphoric acid (HPM)-based complex (H2 PI)2(H 3 O)[PMo12O 40] [Mo2 O5 (H2 O)2 (PI)2 ]?11H2 O (PI-HPM) was prepared by modification with picolinic acid (HPI) and characterized by the methods of Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG), X-ray powder and single crystal diffraction. The complex retained the classical Keggin structure of bulk HPM, there were some strong hydrogen bonds existing between the [PMo12 O40 ]3- polyanion, the [Mo2 O5 (H2 O)2 (PI)2 ] coordination moiety, the protonated HPI and the lattice water molecules. Then PI-HPM was employed as heterogeneous catalyst for esterification reaction to evaluate its acid-catalytic activity. The complex exhibited high activity and good durability in reaction mixtures, indicating that it was a promising heterogeneous acid catalyst for esterification that including the conversion of oleic acid to oleates.
- Liu, Lijun,Wang, Honghong,Gong, Shuwen,Lu, Jing,Zhang, Qian
-
p. 1007 - 1013
(2016/06/15)
-
- Comprising zwitterionic and/or acid-functionalized ion liquid palladium catalyst system
-
The present invention concerns a catalyst system in particular a catalyst system comprising Palladium (Pd), a zwitterion and/or an acid-functionalized ionic liquid, and one or more phosphine ligands, wherein the Pd catalyst can be provided by a complex precursor, such as Pd(CH3COO)2, PdCI2, Pd(CH3COCHCOCH3), Pd (CF3COO)2, Pd(PPh3)4 or Pd2(dibenzylideneacetone)3. Such catalyst systems can be used for e.g. alkoxycarbonylation reactions, carboxylation reactions, and/or in a co-polymerization reaction, e.g. in the production of methyl propionate and/or propanoic acid, optionally in processes forming methyl methacrylate and/or methacrylic acid. Catalyst systems according to the invention are suitable for reactions forming separable product and catalyst phases and supported ionic liquid phase SILP applications.
- -
-
Paragraph 0206-0208
(2017/01/26)
-
- Characterization and Crystal Structure of a Robust Cyclohexanone Monooxygenase
-
Cyclohexanone monooxygenase (CHMO) is a promising biocatalyst for industrial reactions owing to its broad substrate spectrum and excellent regio-, chemo-, and enantioselectivity. However, the low stability of many Baeyer–Villiger monooxygenases is an obstacle for their exploitation in industry. Characterization and crystal structure determination of a robust CHMO from Thermocrispum municipale is reported. The enzyme efficiently converts a variety of aliphatic, aromatic, and cyclic ketones, as well as prochiral sulfides. A compact substrate-binding cavity explains its preference for small rather than bulky substrates. Small-scale conversions with either purified enzyme or whole cells demonstrated the remarkable properties of this newly discovered CHMO. The exceptional solvent tolerance and thermostability make the enzyme very attractive for biotechnology.
- Romero, Elvira,Castellanos, J. Rubén Gómez,Mattevi, Andrea,Fraaije, Marco W.
-
supporting information
p. 15852 - 15855
(2016/12/16)
-
- A producing propionic acid methyl ester reaction device and method
-
The invention relates to a reaction device and a reaction method for producing methyl propionate. The reaction device comprises a static-state mixer, a carbonylation reactor, a flash evaporator, a light component removal tower, a catalyst recycling reactor and a liquid-liquid separation tower. According to the device and the method, a product which contains tar and is discharged by the carbonylation reactor is subjected to flash evaporation and separation; byproducts with low molecular weight produced in the reaction process is separated by using the light component removal tower; precious metal ions, methanol, propionic acid and methyl propionate are extracted by using warm water; a part of heavy phases which come out of the flash evaporator is fully mixed with the water, so that a part of organic matters with low molecular weight in the heavy phase and the precious metal ions are dissolved into a water phase; the separation of the tar and the water phase is realized in the liquid-liquid separation tower, and a water-phase mixture is finally sent back to the carbonylation reactor, so that the accumulation of the tar in the reaction system is reduced, and the loss of methanol is reduced.
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-
Paragraph 0024-0030
(2017/04/03)
-
- CATALYST FOR THE GAS PHASE PRODUCTION OF CARBOXYLIC ACIDS
-
Carboxylic acids are prepared by a one-step gas phase process comprising the step of contacting under halogen-free hydroxycarbonylation conditions an alkene, carbon monoxide, water, and a solid sulfide-containing catalyst.
- -
-
Paragraph 0031; 0035
(2016/12/12)
-
- α-Methylenation of Methyl Propanoate by the Catalytic Dehydrogenation of Methanol
-
A one-pot system for the conversion of methyl propanoate (MeP) to methyl methacrylate (MMA) has been investigated. In particular, this study is focused on the possibility of performing catalytic dehydrogenation of methanol for the in situ production of anhydrous formaldehyde, which is then consumed in a one-pot base-catalysed condensation with MeP to afford methyl 3-hydroxy-2-methylpropanoate, which spontaneously dehydrogenates to MMA, some of which is subsequently hydrogenated to methyl 2-methypropanoate (MiBu).
- Lorusso, Patrizia,Coetzee, Jacorien,Eastham, Graham R.,Cole-Hamilton, David J.
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p. 222 - 227
(2016/01/26)
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- CONTINUOUS PROCESS FOR THE CARBONYLATION OF ETHYLENE
-
A continuous process for the production of an alkyl ester product is described. The process includes the steps of carbonylating ethylene with carbon monoxide in the presence of C1-6 alkanol co-reactant to form the alkyl ester product. The carbonylation takes place in the presence of a catalyst system that includes (a) a bidentate ligand, (b) a catalytic metal selected from a group 8, 9 or 10 metal or a compound thereof, and (c) a sulphonic acid capable of forming an acid alkyl ester with the C1-6 alkanol. The process includes the step of separating the alkyl ester product from a carbonylated crude product stream by treatment effective to vaporizing the alkyl ester product in a single stage flash distillation column and providing a purified alkyl ester product stream separated from the bidentate ligand and catalytic metal.
- -
-
Paragraph 0319-0330
(2015/04/15)
-
- GAS PHASE PRODUCTION OF ALKYL ALKANOATE
-
Alkyl alkanoates, e.g., methyl propionate, are made by a gas phase process comprising the step of contacting under carbonylation conditions an alkene (e.g., ethylene), carbon monoxide, an alkanol (e.g., methanol), and a solid sulfide-based metal catalyst (e.g., iron sulfide). The alkyl alkanoate can be converted in a second step to an alkyl ester of an aliphatic carboxylic acid, e.g., methyl methacrylate, through condensation with an aldehyde, e.g., formaldehyde.
- -
-
Paragraph 0027; 0028
(2015/04/15)
-
- An Empirical Study of Phosphine Ligands for the Methoxycarbonylation of Medium-Chain Alkenes
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The methoxycarbonylation reaction provides a route to the synthesis of esters from medium-chain alkenes that may be used as fuel supplements. However, the known productive catalytic systems are expensive and/or unstable at elevated temperatures. Most of the data available on the methoxycarbonylation of alkenes is derived from ethylene and styrene as substrates. To broaden the scope, we conducted a comparative study of a range of phosphine ligands under comparable conditions for the methoxycarbonylation of 1-octene. The results demonstrate that a number of ligand structural motifs facilitate the process effectually. Furthermore, the critical importance of alkene isomerization and the acid/ligand and Pd/ligand ratios are presented.
- Holzapfel, Cedric,Bredenkamp, Tyler
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p. 2598 - 2606
(2015/09/15)
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- IMPROVED CARBONYLATION PROCESS
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PROBLEM TO BE SOLVED: To provide an improved carbonylation process for ethylenic unsaturated compounds and especially a method giving an improved turnover number(TON) of catalyst system used in carbonylation. SOLUTION: A catalyst system is produced by combining (a) one or more of metals of the groups 8, 9 and 10 and their suitable compounds, (b) a ligand of formula (I) and, if necessary, (c) an anion source. A carbonylation process includes a step of adding water or a supply source of water to the catalyst system and is preferably carried out in the presence of an electrically positive metal. In formula (I), X3 and X4 are independently a monovalent group containing up to 30 atoms or together constitute a divalent group containing up to 40 atoms; X5 is a group containing up to 400 atoms; and Q1 is phosphorus, arsenic or antimony. COPYRIGHT: (C)2016,JPOandINPIT
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Paragraph 0253; 0254; 0255; 0256; 0257
(2016/10/07)
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