292638-85-8Relevant academic research and scientific papers
A green route to methyl acrylate and acrylic acid by an aldol condensation reaction over H-ZSM-35 zeolite catalysts
Ma, Zhanling,Ma, Xiangang,Liu, Hongchao,He, Yanli,Zhu, Wenliang,Guo, Xinwen,Liu, Zhongmin
, p. 9071 - 9074 (2017)
A one-step aldol condensation reaction to produce MA and AA is a green and promising strategy. Here, the aldol condensation reaction was first conducted with DMM and MAc over different types of zeolite catalysts. The H-ZSM-35 zeolite demonstrates excellent catalytic performance with a DMM conversion of 100% and a MA + AA selectivity of up to 86.2% and superior regeneration ability, with great potential for industrial operation.
Propylene polymerization with 1,2′-bridged bis(indenyl)zirconium dichlorides
Finze, Maik,Reybuck, Sarah E.,Waymouth, Robert M.
, p. 9325 - 9334 (2003)
A series of C1 symmetric, 1,2′-bridged bis(indenyl)zirconium dichlorides were prepared to study the effect of ligand substitution, symmetry, and bridge identity on the stereoselectivity of propylene polymerization. Unsubstituted [1-(1-indenyl)-2-(2-indenyl)ethane]zirconium dichloride, Et(2-Ind)(1-Ind)-ZrCl2 (1), was synthesized, and its propylene polymerization behavior was compared to three 2-phenyl-substituted complexes with different bridges: [2-(2-indenyl)-1-(2-phenyl-1-indenyl)ethane]zirconium dichloride, Et(2-Ind)(2-Ph-1-Ind)ZrCl2 (2), [(2-indenyl)-(2-phenyl-1-indenyl)dimethylsilyl] zirconium dichloride, Me2Si(2-Ind)(2-Ph-1-Ind)ZrCl2 (3), and [(2-indenyl)-(2-phenyl-1-indenyl)methane]zirconium dichloride, CH2(2-Ind)(2-Ph-1-Ind)ZrCl2 (4). The polymerization activity, polypropylene molecular weight, and microstructure were dependent upon the identity of the bridge and the substitution patterns on the metallocenes. Metallocenes 1, 2, 3, and 4 are characterized by a gauche orientation of the indenyl ligands, in contrast to the anti or syn orientation of 1,1′-bridged ansa-bis(indenyl)metallocenes. The gauche metallocene 3 yields a polypropylene of intermediate isotacticity ([mmmm] = 58%) when compared to the C2 symmetric anti-Me2Si(2-phenyl-1-indenyl)2ZrCl2 ([mmmm] = 86%) and the Cs symmetric syn-Me2Si(2-phenyl-1-indenyl)2ZrCl2 ([mmmm] = 7%). The gauche metallocene 2 yielded the most highly isotactic polypropylene ([mmmm] = 74%). Analysis of the sequence distributions of the polypropylenes derived from metallocenes 1-4 reveals a predominance of [mrrm] stereoerrors. The high stereoselectivity of the bridged metallocenes 1-4 implies that gauche conformations may be responsible for some of the higher tacticity fractions observed in polypropylenes derived from the unbridged 2-arylindene metallocenes.
Highly Catalytic Activity of Ba/Γ-Ti–Al2O3 Catalyst for Aldol Condensation of Methyl Acetate with Formaldehyde
Bao, Qiang,Qi, Hui,Zhang, Chunlei,Ning, Chunli,Zhang, Yi,Jiang, Ye,Wu, Yifan,Gui, Wenying,Wang, Zhenlu
, p. 3402 - 3412 (2018)
Abstract: In this work, titanium-doped mesoporous Al2O3 (γ-Ti–Al2O3) was prepared by an evaporation-induced self-assembly method and used as a carrier of Ba/γ-Ti–Al2O3 catalyst to catalyze the aldol condensation of methyl acetate with formaldehyde to methyl acrylate in a fixed-bed reactor. The catalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, N2 adsorption–desorption, pyridine absorption performed via Fourier transform infrared spectroscope (Py-IR), and NH3 and CO2 temperature-programmed desorption (NH3 and CO2-TPD). Experimental results indicated that the doping of the titanium species into the frame work of mesoporous Al2O3 (γ-Ti–Al2O3) had a significant influence on the catalytic activity via modifying the acid–base surface properties of the catalyst. Furthermore, the Ba/γ-Ti–Al2O3 catalyst demonstrated excellent catalytic performance, with a methyl acetate conversion rate of 50% and methyl acrylate selectivity up to 90.2%. Compared with the Ba/Al2O3 catalyst, the Ba/γ-Ti–Al2O3 catalyst had better catalytic activity, stability and potential for practical application, which was likely due to an increased number of Lewis acid sites, especially the medium acid sites. Graphical Abstract: Barium supported mesoporous γ-Ti–Al2O3 catalyst was found to be an effective catalyst for vapor phase aldol condensation of methyl acetate with formaldehyde. [Figure not available: see fulltext.].
ON THE REACTIVITY OF 3,4-DIMETHOXYCARBONYL-2-PYRAZOLINES WITH DIMETHYL ACETYLENEDICARBOXYLATE
Schultz, Arthur G.,Ravichandran, Ramanathan
, p. 1771 - 1774 (1981)
The title pyrazolines react with dimethyl acetylenedicarboxylate to give 1-alkyl-3,4,5-trimethoxycarbonylpyrazoles.
Reductive functionalization of carbon dioxide to methyl acrylate at zerovalent tungsten
Wolfe, Justin M.,Bernskoetter, Wesley H.
, p. 10763 - 10768 (2012)
Alkali metal reduction of tungsten tetrachloride in the presence of excess trimethylphosphite and ethylene affords moderate yields of trans- tetrakis(trimethylphosphite)tungsten bis(ethylene). This easily prepared species bearing inexpensive ancillary lig
The 2V-P,N polymer supported palladium catalyst for methoxycarbonylation of acetylene
Chen, Xingkun,Zhu, Hejun,Wang, Tao,Li, Cunyao,Yan, Li,Jiang, Miao,Liu, Jia,Sun, Xueping,Jiang, Zheng,Ding, Yunjie
, p. 37 - 46 (2016)
Heterogenization of homogeneous catalyst by immobilizing complex on the surface of polymer supports promotes the design of the catalysts which combine the advantages of heterogeneous and homogeneous catalysts. The porous 2-vinyl-functional diphenyl-2-pyri
Preparation of Cs-La-Sb/SiO2 catalyst and its performance for the synthesis of methyl acrylate by aldol condensation
Wang, Yanan,Lang, Xuewei,Zhao, Guoqing,Chen, Huanhui,Fan, Yiwei,Yu, Linqing,Ma, Xiuxiu,Zhu, Zhirong
, p. 32826 - 32834 (2015)
A variety of cesium supported catalysts with amorphous SiO2 as a carrier were prepared by vacuum impregnation and ultrasonic impregnation methods, which were used for the synthesis of methyl acrylate by aldol condensation of methyl acetate and formaldehyde. The as-prepared catalysts were characterized by XRD, N2 adsorption-desorption, NH3-TPD, CO2-TPD, XPS, ICP and TG. The results indicated that the bifunctional Cs-La-Sb/SiO2 showed a high conversion of methyl acetate as well as a high yield of methyl acrylate, which was attributed to the weak acid-base sites and the formation of basic Cs-O-Si species with the addition of antimony and lanthanum, respectively. Furthermore, Cs-La-Sb/SiO2-(V) prepared by vacuum impregnation showed a high initial catalytic activity, but its activity sharply decreased due to the loss of active species. Comparatively, Cs-La-Sb/SiO2-(U) prepared by ultrasonic impregnation showed a good stability owing to the cavitation effect of ultrasonic waves. The conversion of methyl acetate and yield of methyl acrylate remained above 20% and 9.0% (based on methyl acetate) for 100 h without obvious deactivation. Moreover, carbon deposition was the main factor for the deactivation of Cs-La-Sb/SiO2-(U), and the coked catalyst could be regenerated by calcination in air. This journal is
Renewable production of acrylic acid and its derivative: New insights into the aldol condensation route over the vanadium phosphorus oxides
Feng, Xinzhen,Sun, Bo,Yao, Yao,Su, Qin,Ji, Weijie,Au, Chak-Tong
, p. 132 - 141 (2014)
Vanadium phosphorus oxides (VPOs) fabricated by employing poly ethylene glycol (PEG) additive were used as catalysts for efficient conversion of acetic acid (methyl acetate) and formaldehyde to acrylic acid (methyl acrylate). The highest formation rate (19.8 μmol gcat-1 min -1) of desired products (acrylic acid + methyl acrylate) was accomplished over a VPO catalyst comprising mainly vanadyl pyrophosphate ((VO)2P2O7) and vanadyl phosphate in δ form (δ-VOPO4). This catalyst is nearly three times more active than the analogue reported in literature. The VPO catalyst activated in 1.5% butane-air is superior to that activated in air or nitrogen. Different from the PEG-derived VPO catalysts for n-butane oxidation to maleic anhydride, a better VPO catalyst for the current reaction requires a higher fraction of δ-VOPO4 entity and contains the medium strong acid sites of high density. Through systematic catalyst characterizations and evaluations, an unambiguous correlation between catalyst structure/constitution and performance was established.
Formation of methyl acrylate from CO2 and ethylene via methylation of nickelalactones
Bruckmeier, Christian,Lehenmeier, Maximilian W.,Reichardt, Robert,Vagin, Sergei,Rieger, Bernhard
, p. 2199 - 2202 (2010)
The nickel-induced coupling of ethylene and CO2 represents a promising pathway toward acrylates. To overcome the high bond dissociation energies of the M-O moieties, we worked out an in situ methylation of nickelalactones to realize the β-hydride elimination and the liberation of the acrylate species.
One-step aldol condensation reaction of dimethoxymethane and methyl acetate over supported Cs/ZSM-35 zeolite catalysts
Ma, Zhanling,Ma, Xiangang,Liu, Hongchao,Zhu, Wenliang,Guo, Xinwen,Liu, Zhongmin
, p. 1129 - 1137 (2018)
This study was performed for the development of a green and promising approach for the synthesis of methyl acrylate and acrylic acid by a one-step aldol condensation reaction of dimethoxymethane and methyl acetate over cesium oxide-supported on ZSM-35 zeo
