554-12-1Relevant articles and documents
Polymer producing palladium complexes of unidentate phosphines in the methoxycarbonylation of ethene
Smith, Graeme,Vautravers, Nicolas R.,Cole-Hamilton, David J.
, p. 872 - 877 (2009)
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
2-Formyl-4-pyrrolidinopyridine (FPP): A new catalyst for the hydroxyl-directed methanolysis of esters
Sammakia, Tarek,Hurley, T. Brian
, p. 8967 - 8968 (1996)
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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
Erdem, Beyhan,Kara, Ali
, p. 219 - 224 (2011)
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).
Oxidative Decarboxylation of Alcohol Hemiacetals of α-Keto Carboxylic Acids with N-Iodosuccinimide
Beebe, Thomas R.,Baldridge, Ruth,Beard, Mark,Cooke, Denette,DeFays, Isabelle,et.al.
, p. 3165 - 3166 (1987)
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Lorette,Brown
, p. 261 (1959)
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Para Hydrogen Induced Polarization in Hydrogenation Reactions Catalyzed by Ruthenium-Phosphine Complexes
Kirss, Rein U.,Eisenschmid, Thomas C.,Eisenberg, Richard
, p. 8564 - 8566 (1988)
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Acid-Promoter-Free Ethylene Methoxycarbonylation over Ru-Clusters/Ceria: The Catalysis of Interfacial Lewis Acid-Base Pair
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
, p. 4172 - 4181 (2018)
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
Borate esters as alternative acid promoters in the palladium-catalyzed methoxycarbonylation of ethylene
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
, p. 2273 - 2275 (2007)
(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
Magnetically-separable Fe3O4@SiO2@SO4-ZrO2 core-shell nanoparticle catalysts for propanoic acid esterification
Tai, Zhijun,Isaacs, Mark A.,Durndell, Lee J.,Parlett, Christopher M.A.,Lee, Adam F.,Wilson, Karen
, p. 137 - 141 (2018)
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.
Homolytic Bond Strength and Radical Generation from (1-Carbomethoxyethyl)pentacarbonylmanganese(I)
Morales-Cerrada, Roberto,Fliedel, Christophe,Gayet, Florence,Ladmiral, Vincent,Améduri, Bruno,Poli, Rinaldo
, (2019)
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.
High-Performance RuCl3 Catalyst Systems for Hydro-Esterification of Methyl Formate and Ethylene
Li, Yan-Ru,Xu, Zhong-Ning,Bai, Bing,Wang, Zhi-Qiao,Guo, Guo-Cong
, p. 769 - 774 (2019)
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.
Light-Responsive, Reversible Emulsification and Demulsification of Oil-in-Water Pickering Emulsions for Catalysis
Li, Zhiyong,Shi, Yunlei,Zhu, Anlian,Zhao, Yuling,Wang, Huiyong,Binks, Bernard P.,Wang, Jianji
supporting information, p. 3928 - 3933 (2020/12/18)
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.
Manganese-Mediated C-C Bond Formation: Alkoxycarbonylation of Organoboranes
Van Putten, Robbert,Filonenko, Georgy A.,Krieger, Annika M.,Lutz, Martin,Pidko, Evgeny A.
supporting information, p. 674 - 681 (2021/04/02)
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.
