- Catalytic performance of functionalized IRMOF-3 for the synthesis of glycerol carbonate from glycerol and urea
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A functionalized isoreticular metal organic framework material, F-IRMOF-3, having a quaternary ammonium group was prepared by fast precipitation and solvothermal method. The synthesized MOFs exhibited good catalytic performance in the synthesis of glycerol carbonate (GC) from glycerol and urea. F-IRMOF-3 having a larger alkyl chain structure and a more nucleophilic counter anion than the synthesized congeners, exhibited better reactivity in the synthesis of GC. The introduction of a ZnO defect into the F-IRMOF-3 structure by fast precipitation was more advantageous for the glycerolysis of urea than the conventional solvothermal method because of the incorporation of acid-base bifunctional active sites by the former method. The effects of reaction parameters such as temperature, reaction time, catalyst loading, and degree of vacuum on the reactivity were also investigated. The F-IRMOF-3 catalyst can be easily recovered and reused without considerable loss of its initial activity. Copyright
- Lee, Sun-Do,Park, Gyung-Ah,Kim, Dong-Woo,Park, Dae-Won
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- Monitoring the catalytic synthesis of glycerol carbonate by real-time attenuated total reflection FTIR spectroscopy
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In situ Attenuated Total Reflectance FTIR spectroscopy was used to study the carbonylation of glycerol with urea. Cobalt oxide nanoparticles, Co 3O4, hierarchically dispersed on zinc oxide microparticles, ZnO, were used as catalysts. The present work demonstrates that in situ real-time attenuated total reflection ATR-FTIR spectroscopy is a valuable tool for monitoring reaction progress and analyzing the reaction mechanism of the synthesis of glycerol carbonate. ATR-FTIR spectroscopy during the carbonylation reaction of glycerol with urea reveals differences in reactivity of various Co3O4/ZnO catalysts, and in particular demonstrates that the first (fast) step in the conversion of glycerol with urea is the formation of glycerol urethane, whereas the consecutive conversion to glycerol carbonate is relatively slow. In addition, possible interactions of the catalytically active sites with in particular the product glycerol carbonate were also evaluated. Interactions of the 2-hydroxyethyl chain of the product with the surface of the catalysts were identified, suggesting product inhibition might be of relevance to the reaction kinetics.
- Calvino-Casilda,Mul,Fernández,Rubio-Marcos,Ba?ares
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- Enzymatic processing of renewable glycerol into value-added glycerol carbonate
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Increased production of biodiesel has led to excess glycerol production worldwide, which has resulted in a significant drop in glycerol prices. Glycerol carbonate is a multifunctional compound used as chemical intermediates, solvents, additives and monomers. In this study, the enzymatic synthesis of glycerol carbonate from glycerol and a dialkyl carbonate was investigated. Glycerol carbonate was formed when reacting glycerol with dimethyl carbonate, diethyl carbonate or dibutyl carbonate in the presence of Candida antarctica lipase B (Novozym 435), using tert-butanol as a solvent. Nearly 100% glycerol conversion was reached after 12 h, with glycerol carbonate being the primary product. The effects of reaction parameters including solvent choice and biocatalyst loading were also examined. The highest activity was found at restricted water conditions and when using tert-butanol as a solvent.
- Cushing, Kerri A.,Peretti, Steven W.
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- Efficient synthesis of glycerol carbonate from glycerol and urea with lanthanum oxide as a solid base catalyst
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Lanthanum oxide catalyst prepared by precipitation method and calcined at 600 °C exhibited better catalytic activity in the catalytic synthesis of glycerol carbonate from glycerol and urea with TOF up to 1506 mmol/g?h. It was proposed that the lanthanum oxide catalyst with more strong basic sites (Td > 400 °C) exhibited higher catalytic activity. Accordingly, the catalyst containing appropriate amount of La2O 2CO3 phase exhibited higher catalytic activity. Moreover, the recycling experiments demonstrated that the catalytic activity can be essentially preserved during the recycling tests investigated.
- Wang, Liguo,Ma, Yubo,Wang, Ying,Liu, Shimin,Deng, Youquan
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- Transesterification of Glycerol to Glycerol Carbonate Using KF/Al 2O3 Catalyst: The Role of Support and Basicity
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Glycerol carbonate was synthesized by transesterification of glycerol with dimethyl carbonate using KF supported catalyst. KF was impregnated on various oxides and non-oxide supports like Al2O3, SiO2, ZnO, ZrO2,
- Sandesh, Swetha,Shanbhag, Ganapati V.,Halgeri
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- Zinc hydroxystannate: A promising solid acid-base bifunctional catalyst
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Zinc hydroxystannate is shown to be a highly active and selective solid bifunctional catalyst for carbonylation of glycerol with urea. It has strong basicity with Lewis acidic Zn, low hygroscopicity and good thermal stability which makes it a potential catalyst for heterogeneous acid-base catalysed reactions. The Royal Society of Chemistry 2014.
- Sandesh, Swetha,Shanbhag, Ganapati V.,Halgeri
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- Design of a technical Mg-Al mixed oxide catalyst for the continuous manufacture of glycerol carbonate
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The availability of a heterogeneous catalyst, which contains cheap and abundant elements, has a scalable synthesis, is highly active and stable, retains its performance upon shaping into a technical form and can be operated in continuous mode, would pave the way for a more ecological and economical production of glycerol carbonate from glycerol and urea. Here, we show that a mixed oxide of Mg and Al is a promising active phase for this reaction. The solid comprises widely available and non-toxic metals, is easily obtained through the thermal decomposition of a hydrotalcite-like material and can almost match the product yield of state-of-the-art Zn-based catalysts, while displaying an outstanding resistance against leaching, which causes the rapid dissolution of the latter. In-depth characterisation uncovered that Lewis-basic centres are crucial to activate glycerol through dehydrogenation. Their concentration was maximised by optimising the composition and calcination temperature of the precursor, thus reaching up to 60% glycerol carbonate yield. Millimeter-sized extrudates featuring comparable basic properties to the powder sample, a well-developed meso- and macroporosity and high mechanical stability are obtained using a natural clay, bentonite, as a binder and thermally activating the hydrotalcite only after shaping. Upon testing in a continuous reactor under tuned conditions of temperature and pressure and in the presence of an aprotic solvent, the system attains the same glycerol yield as in the batch tests. During 100 h on stream, its activity decreases by 20% due to fouling, but can be fully restored upon burning-off of the carbonaceous deposits. This work discloses the development of a green material that exhibits high efficacy in a sustainable transformation, highlighting key parameters that should be generally taken into account in the design of an industrially relevant chemocatalytic technology.
- Lari,De Moura,Weimann,Mitchell,Mondelli,Pérez-Ramírez
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- Ultrasound assisted enzyme catalyzed synthesis of glycerol carbonate from glycerol and dimethyl carbonate
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The present work illustrates the transesterification of glycerol to glycerol carbonate (GlyC) from dimethyl carbonate (DMC) using commercial immobilized lipase (Novozym 435) under ultrasonic irradiation. The experiments were performed in a batch reactor placed in an ultrasonic water bath using a sequence of experimental protocol to evaluate the effects of temperature, molar ratios of substrates, enzyme loading, duty cycle and ultrasound power on the conversion of glycerol to GlyC. It has been found that ultrasound-assisted lipase-catalyzed transesterification of glycerol would be a potential alternative to conventional alkali-catalyzed method, as high conversion (99.75%) was obtained at mild operating conditions: molar ratio of DMC to glycerol 3:1, catalyst amount of 13% (w/w), lower power input (100 W), duty cycle 50% and temperature (60 °C) in a relatively short reaction time (4 h) using Novozym 435 as catalyst. Ultrasound reduces the reaction time up to 4 h as compared to conventional stirring method (14 h) catalyzed by Novozym 435. The repeated use of the catalyst under the optimum experimental condition resulted in decay in both enzyme activity and product conversion.
- Waghmare, Govind V.,Vetal, Mangesh D.,Rathod, Virendra K.
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- Valorization of bio-glycerol: New catalytic materials for the synthesis of glycerol carbonate via glycerolysis of urea
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The glycerolysis of urea plays an important role in the conversion of glycerol into glycerol carbonate because it is a phosgene-free process that uses easily available and low-cost raw materials that have a low toxicity. γ-Zirconium phosphate shows a good
- Aresta, Michele,Dibenedetto, Angela,Nocito, Francesco,Ferragina, Carla
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- Catalytic performance of ion-exchanged montmorillonite with quaternary ammonium salts for the glycerolysis of urea
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Various quaternary ammonium salt (QX) ionic liquids immobilized onto montmorillonite clay (Q-MMT) were prepared by ion-exchange reaction between the tetra-alkyl ammonium salts and ions in the clay interlayer. The Q-MMTs were characterized by elemental ana
- Lee, Sun-Do,Park, Moon-Seok,Kim, Dong-Woo,Kim, Il,Park, Dae-Won
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- Hydroxy-functionalized imidazolium bromides as catalysts for the cycloaddition of CO2 and epoxides to cyclic carbonates
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Hydroxy-functionalized mono- and bisimidazolium bromides were synthesized and applied as catalysts for the cycloaddition of CO2 and epoxides to cyclic carbonates. A catalyst screening showed the influence of the number of protic hydrogen atoms at the cation for the activation of epoxides. The most active catalyst operates at very mild reaction conditions (70 °C, 0.4 MPa CO2) and can be easily recycled ten times without loss of activity.
- Anthofer, Michael H.,Wilhelm, Michael E.,Cokoja, Mirza,Drees, Markus,Herrmann, Wolfgang A.,Kühn, Fritz E.
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- Lithium Organoaluminate Complexes as Catalysts for the Conversion of CO2 into Cyclic Carbonates
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Four lithium organoaluminate complexes containing bidentate pyrrolyl ligand were successfully synthesized, and their structural features were provided. These complexes were used as catalysts for chemical fixation of carbon dioxide with epoxides under mild conditions. Among them, complex {[C4H3N(AlEt3)(2-CH2NHLitBu)][C4H3NLi(2-CH2NHtBu)]}2 (4), in conjunction with tetrabutyl-ammonium iodide (TBAI) as cocatalyst, exhibits higher catalytic activities than other lithium organoaluminates. Epoxides reacted with CO2 at 50 °C and 1 atm pressure to give the corresponding cyclic carbonates in yields of 62–99 percent.
- Guo, Zhiqiang,Xu, Yuan,Chao, Jianbin,Wei, Xuehong
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- Synthesis of glycerol carbonate from glycerol and urea using zinc-containing solid catalysts: A homogeneous reaction
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Zinc-containing solid catalysts (zinc oxide, smectite, hydrotalcite) and several inorganic zinc salts were used to produce glycerol carbonate from glycerol and urea under solvent-free conditions at 130 °C and at a reduced pressure of 3 kPa. The leaching of Zn species was observed to occur for the solid catalysts, and the carbonate yield was shown to be correlated with the amount of zinc species dissolved into the liquid phase with a single relationship in common for all the catalysts employed. The reaction was also indicated to continue in the liquid phase alone, after the solid catalysts were removed from the reaction mixtures by filtration. The results obtained reveal that the reaction takes place homogeneously in the liquid phase irrespective of the parent solid catalysts used. Possible structure of active Zn species was discussed from the results of reaction runs under different conditions and Fourier transform infrared spectroscopy measurements of the liquid phase after the reaction.
- Fujita, Shin-Ichiro,Yamanishi, Yuki,Arai, Masahiko
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- Hydrotalcites Promoted by NaAlO2 as Strongly Basic Catalysts with Record Activity in Glycerol Carbonate Synthesis
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A new type of highly basic catalysts is obtained by promoting Mg–Al layered double hydroxides with sodium aluminate. The Mg–Al mixed oxides obtained by the calcination of pristine hydrotalcites are poorly active in the synthesis of glycerol carbonate from glycerol and dimethyl carbonate (DCM). Pure sodium aluminate on the other hand is highly active in this reaction, but it is also highly corrosive, making its handling problematic. Remarkably, promoting hydrotalcites with low amounts of sodium aluminate is sufficient to reach high yields. At 90 °C, with 3 wt % catalyst and with a DMC/glycerol ratio of 2:1, a glycerol conversion of 92 % was achieved after 30 min over the 10 wt % NaAlO2/hydrotalcite catalyst with almost 100 % selectivity towards glycerol carbonate. The texture and the crystallinity of the catalysts were strongly affected by the addition of NaAlO2. The high activity was clearly correlated with the boost in basicity brought about by sodium aluminate promotion. Whereas pristine hydrotalcites possess only weak basic sites, the basicity of the catalysts increased drastically upon promotion with NaAlO2, both in amount and strength. Diffuse reflectance infrared spectroscopy coupled with CO2 adsorption measurements revealed the presence of surface carbonates arising from strongly basic sites. Importantly, our study demonstrates that these basic catalysts are truly heterogeneous, stable, and reusable.
- Ramesh, Sreerangappa,Devred, Fran?ois,van den Biggelaar, Ludivine,Debecker, Damien P.
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- Solvent-free carbonylation of glycerol with urea using metal loaded MCM-41 catalysts
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Reacting glycerol with urea is the most attractive option for the production of glycerol carbonate (GC) as it utilizes two inexpensive chemicals readily available in the chemical cycle. The overall result is the chemical fixation of carbon dioxide. A Zn/MCM-41(im) catalyst prepared by a wet impregnation method exhibited excellent activity for the reaction of glycerol and urea with 75% glycerol conversion and 98% selectivity to GC. Such excellent activity of the catalyst is explained based on the presence of both basic and acidic sites on the same catalyst which activates the glycerol and urea molecules, respectively. This journal is
- Kondawar,Potdar,Rode
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- Novel Bifunctional Zn-Sn Composite Oxide Catalyst for the Selective Synthesis of Glycerol Carbonate by Carbonylation of Glycerol with Urea
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A novel Zn-Sn composite oxide is reported as a solid bifunctional catalyst for glycerol carbonylation to give glycerol carbonate in high yields. It was prepared by coprecipitation, solid-state and evaporation methods. Physico-chemical properties of the catalysts were investigated by XRD, N2 sorption, temperature-programmed desorption, SEM, and TEM techniques. Coprecipitation was found to be better than the other two methods for carbonylation of glycerol. Higher activity of the catalyst was attributed to a high amount of active sites. A series of Zn-Sn composite oxides with different metal contents and effect of calcination on glycerol carbonate synthesis were also studied. The correlation of activity with total active sites of the catalyst was obtained. Zn-Sn composite catalyst with Zn/Sn molar ratio=2:1 calcined at 600 °C exhibited 96.0 % glycerol conversion with 99.6 % selectivity towards glycerol carbonate under optimized reaction conditions. The catalyst was recycled four times with a marginal decrease in activity.
- Manjunathan, Pandian,Ravishankar, Raman,Shanbhag, Ganapati V.
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- Synthesis of glycerol carbonate from glycerol and dimethyl carbonate over DABCO embedded porous organic polymer as a bifunctional and robust catalyst
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A large surplus of glycerol from the rapidly growing biodiesel industry has led to the conversion of glycerol into higher value-added products being of great industrial importance. In this paper, a promising route for the synthesis of glycerol carbonate from glycerol and dimethyl carbonate is described using DABCO (1,4-diazabicyclo[2.2.2]octane) embedded porous organic polymer as an efficient and robust catalyst. The porous catalyst with base sites and hydrophilic units (monoquaternized DABCO) was facilely synthesized through a one-pot radical copolymerization of divinylbenzene and vinyl functionalized DABCO monomer. By simply varying the mass ratio between divinylbenzene/DABCO monomer, the surface area, pore volume and surface wettability of the catalyst can be easily adjusted. Results of activity evaluations indicated that the catalyst with high surface area and excellent amphiphilicity exhibits much higher activity than other samples due to the enhanced accessibility of catalytic sites and mass transfer efficiency. Under the optimum reaction conditions, a 0.75 mol% catalyst loading is sufficient for excellent yield of glycerol carbonate in 60 min. Moreover, the optimized catalyst also shows excellent reusability and could be reused up to 13 consecutive recycles without obvious deactivation in activity.
- Wan, Yali,Lei, Yizhu,Lan, Guosong,Liu, Dingfu,Li, Guangxing,Bai, Rongxian
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- A selective synthesis of glycerol carbonate from glycerol and urea over Sn(OH)2: A solid and recyclable: In situ generated catalyst
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In this work, we report a selective and straightforward process to synthesize glycerol carbonate from urea and glycerol using a simple but commercially unavailable catalyst (Sn(OH)2). This catalyst was generated in situ from the reaction of Sn(ii) halides and urea during the glycerol carbonatation process. Effects of main reaction parameters (i.e., temperature, molar ratio of urea to glycerol, catalyst concentration) were investigated. Different tin halides were assessed as catalytic precursors, with SnCl2 being the most efficient. We found that Sn(OH)2-catalyzed glycerol carbonation reactions with urea achieved high conversion and selectivity (ca. 87 and 85%, respectively). The samples of Sn(OH)2 generated in situ or previously synthesized were equally active and selective catalysts toward glycerol carbonate were successfully reutilized without loss activity. This is a very attractive route based on two inexpensive and readily available feedstocks in a chemical cycle that, overall, results in the chemical fixation of carbon dioxide and, concomitantly, adds value to glycerol, a biodiesel byproduct.
- Chaves, Diego M.,Da Silva, Márcio J.
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- Preparation of nano-CaO and catalyzing tri-component coupling transesterification to produce biodiesel
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Nano-CaO with different particle sizes and crystallinity was prepared by sol-gel method. A tri-component coupling transesterification of rapeseed oil/dimethyl carbonate (DMC)/methanol was used to determine the viability of prepared nano-CaO as a basic catalyst for biodiesel synthesis. Nano-CaO exhibits better catalytic performance than commercial CaO for biodiesel production under same reaction condition. At 1:1:8 molar ratio of oil to DMC to methanol, 5 wt% nano-CaO catalyst (calcined at 800 °C), and 65 °C reaction temperature, the reaction gave the best results, and the fatty acid methyl ester yield exceeded 92% at 4 h which was 2 h shorter than that of commercial CaO. The catalyst calcined under different temperature has been characterized by BET, CO2-TPD, TGA, XRD, and SEM. As the results shows that nano-CaO calcined at 800 °C exhibited the most active which should be contributed to the presence of good dispersivity, large surface area and pore volume.
- Tang, Ying,Yang, Ying,Liu, Huan,Yan, Tianlan,Zhang, Zhifang
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- Synthesis of glycerol carbonate from glycerol and urea over tin-tungsten mixed oxide catalysts
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Tin-tungsten mixed oxide catalysts with varying their mole ratio were prepared by co-precipitation method. The catalysts physico-chemical properties were derived from FT-infrared, Laser Raman, X-ray diffraction, UV-Vis DRS, BET surface area and temperatur
- Jagadeeswaraiah,Kumar, Ch. Ramesh,Prasad, P.S. Sai,Loridant,Lingaiah
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- A unique zinc-organic framework constructed through: In situ ligand synthesis for conversion of CO2 under mild conditions and as a luminescence sensor for Cr2O72-/CrO42-
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A novel zinc-organic framework, {[Zn3(tza)2(μ2-OH)2(H2O)2]·H2O}n (1) (H2tza = 1H-tetrazolate-5-acetic acid), was synthesized through an in situ generated tetrazole ligand under hydrothermal conditions. In compound 1, tza2- ligands and Zn2+ are interlinked to form 2D layers, which are further pillared through μ2-OH groups to generate a 3D framework. Thermogravimetric analysis and powder X-ray diffraction confirm that 1 has high thermal stability, pH stability and solvent stability. Catalytic studies show that 1 exhibits excellent catalytic ability for the cycloaddition of CO2 with epoxides under 50 °C and 0.1 MPa. Importantly, 1 can be reused at least six times. Furthermore, luminescence investigations indicate that 1 can serve as a recyclable luminescence sensor to efficiently detect Cr2O72-/CrO42-, and the detection limit can reach 10-6 mol L-1 and 4 × 10-6 mol L-1, respectively.
- Song, Tian-Qun,Dong, Jie,Gao, Hong-Ling,Cui, Jian-Zhong,Zhao, Bin
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- Synthesis, characterization and reactivity of a six-membered cyclic glycerol carbonate bearing a free hydroxyl group
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Five- and six-membered cyclic carbonates have recently become popular as starting materials for the synthesis of polycarbonates via ring opening polymerization or synthesis of environmentally friendly non-isocyanate polyurethanes. In many cases a five-membered glycerol carbonate has been used in these applications. However, the simplest derivative of glycerol, a six-membered cyclic glycerol carbonate (5-hydroxy-1,3-dioxan-2-one), has not been reported so far. In this work, for the first time, we report a procedure for the synthesis of this monomer from glycerol. The product was characterized by 1H NMR, 13C NMR, and FTIR spectroscopy and X-ray diffraction measurements. Further, the synthesis of bis(2-oxo-1,3-dioxan-5-yl) sebacate, a biscyclic six-membered carbonate, was described. The reactivities of 5-hydroxy-1,3-dioxan-2-one and its biscyclic ester derivative were investigated. No ring opening polymerization of both the monomers was observed, instead an isomerization to appropriate five-membered cyclic carbonates occurred. Unfortunately, the protection of the hydroxyl group 2 with an ester type substituent does not protect it against isomerisation.
- Tryznowski,Zo?ek-Tryznowska,?widerska,Parzuchowski
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- Organic-inorganic hybrids of imidazole complexes of zinc (II) for catalysts in the glycerolysis of urea
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Bis(alkylimidazole) complexes of zinc, (Rlm)2ZnX2, were prepared by a metal insertion reaction. The synthesized (Rlm) 2ZnX2 exhibited good catalytic performance during synthesis of glycerol carbonate (GC) from glycerol and urea. (HEIm) 2ZnCI2 with a hydroxyl group exhibited the highest GC yield during glycerolysis of urea owing to incorporation of acid-base bifunctional active sites. (Elm)2ZnX2 catalysts based on different halide anions showed increased reactivity as Cl- -, which is the order of nucleophilicity The effects of reaction parameters such as temperature, reaction time, catalyst loading, and degree of vacuum on the reactivity were also investigated. Copyright
- Kim, Dong-Woo,Park, Dae-Won
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- Nanoheterogeneous Catalytic Cotransformation of Polyatomic Alcohols and Carbamides
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The interaction of ethylene glycol and glycerol with carbamide in the presence of nanosized cobalt oxide obtained by the decomposition of cobalt(II) acetylacetonate in diphenyl ether is studied. The average size of the nanosized catalyst particles is 8–10 nm. The effect of nanoheterogeneous catalysis on the cyclocondensation of polyatomic alcohols with carbamide is investigated. A high capacity of the nanosized catalyst in this process is found 150 g(cyclic carbonate)/(g(catalyst) h), which is more than 100 times higher than the capacity of conventional catalysts.
- Lyadov,Kochubeev,Markova,Khadzhiev
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- Solventless synthesis of cyclic carbonates by direct utilization of CO2 using nanocrystalline lithium promoted magnesia
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Cyclic carbonates are industrially important chemicals. In this work, an efficient synthesis of cyclic carbonate was achieved by cyclization of epoxide with CO2 using nanocrystalline lithium promoted magnesia (Li-MgO), without using any co-catalyst or solvent. A series of Li-MgO were prepared by gel combustion method and well characterized. Li-MgO forms active F-centers (crystallographic defect) due to the difference in valence state of lithium (Li+) and magnesium (Mg2+) and acts as an active site for CO2 activation. In the synthesis of 4-(chloromethyl)-1,3-dioxolan-2-one from epichlorohydrin, 0.75% (w/w) Li-MgO was the most active catalyst for CO2 fixation into cyclic carbonate with excellent conversion (~98%) and selectivity (100%), at 130 °C and 3 MPa of CO2 pressure. The catalyst showed structural stability and was reused for three cycles without loss of activity. The current synthesis protocol is 100% atom-efficient and thus was extended to a variety of substrates. Langmuir- Hinshelwood-Hougen-Watson (LHHW) type of mechanism was proposed and kinetics studied. Both reactants are strongly adsorbed making the overall reaction zero order with an apparent activation energy of 15.14 kcal/mol.
- Rasal, Kalidas B.,Yadav, Ganapati D.,Koskinen, Rauli,Keiski, Riitta
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- Continuous Synthesis of Glycerol Carbonate by Transesterification of Glycerol with Dimethyl Carbonate Over Fe–La Mixed Oxide Catalysts
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Abstract: Transesterification of glycerol with dimethyl carbonate to produce glycerol carbonate was studied under continuous reaction over Fe–La mixed oxide catalysts. A series of Fe–La oxide catalysts with different molar compositions were synthesized by co-precipitation method. Surface and structural investigations of the catalysts were carried using N2 physisorption, powder X-ray diffraction, temperature-programmed desorption, X-ray photoelectron spectroscopy, FT-infra red spectroscopy, scanning electron microscopy and Laser Raman spectroscopy. Glycerol carbonate yield was influenced by the molar ratios of Fe/La and catalyst calcination temperature, which are responsible for the variation in acid–base properties of the catalysts. The catalyst with a molar ratio of 1:1 calcined at 550?°C exhibited superior activity with 71% yield of glycerol carbonate. The synergistic effect between Fe–La oxides and the formation of LaFeO3 perovskite structure are responsible for the high activity of the catalyst. The catalyst exhibited unprecedented stability over 100?h during the time on stream analysis. Graphic Abstract: [Figure not available: see fulltext.]
- Pattanaik, Piyusa P.,Kumar, P. Mahesh,Raju,Lingaiah
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- Microwave assisted synthesis of glycerol carbonate over LDH catalyst: Activity restoration through rehydration and reconstruction
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Zn-Al layer double hydroxide (LDH), as synthesized, was found to be an effective base catalyst for microwave (MW) assisted conversion of glycerol to glycerol carbonate. The used catalyst deactivated after three successive usages in the reaction necessitat
- Prakruthi,Jai Prakash,Bhat
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- A Ni3O-cluster based porous MOF for catalytic conversion of CO2 to cyclic carbonates
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A novel Ni3O-based MOF, {[Ni3HL(μ3-OH)(H2O)2]?3(H2O)?DMA}n (1), was constructed based on an organosilicon hexacarboxylic acid linker of 5,5′,5''-(methylsilanetriyl)triisophthalic
- Yang, Yang,Guo, Zhenli,Chen, Xiao-Hong,Liu, Jinglin
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- Isolation and characterization of intermediate catalytic species in the Zn-catalyzed glycerolysis of urea
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Homogeneous zinc-catalyzed synthesis of glycerol carbonate from the reaction of glycerol with urea was investigated. Among the zinc-based catalysts tested, ZnCl2 showed the highest catalytic activity. Spectroscopic and elemental analyses of the
- Park, Jong-Ho,Choi, Ji Sik,Woo, Soo Kyoung,Lee, Sang Deuk,Cheong, Minserk,Kim, Hoon Sik,Lee, Hyunjoo
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- Synthesis of glycerol carbonate over a 2D coordination polymer built with Nd3+ ions and organic ligands
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In this work, a two-dimensional coordination polymer was synthesized and the structure was determined by single-crystal X-ray diffraction. The crystal structure belongs to the space group Pna21 and was characterized by Raman and FT-infrared spectroscopy, powder X-ray diffraction and Brunauer-Emmett-Teller surface area analysis. Catalyst activities were evaluated through the synthesis of glycerol carbonate from glycerol and urea using a batch reactor. After the optimization of both reaction and reaction conditions, the activity results showed that the coordination polymer used as a heterogeneous catalyst has good values of conversions and selectivity for the manufacturing of glycerol carbonate in a fine-chemical process. The analysis of powder X-ray diffraction and spectroscopy for the coordination polymer employed, before and after the reaction, shows that some changes have taken place in the crystal structure during the process, in spite of a recovery at the end of the reaction. The advantages and limitations of the coordination polymer were discussed and compared with those of the previous heterogeneous catalysts in the literature.
- Franco, Chris H. J.,Chagas, Poliane,Caldeira, Gabriela S.,Oliveira, Luiz C. A.,De Souza, Patterson P.,Leit?o, Alexandre A.,Amarante, Giovanni W.,Diniz, Renata
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- Incorporation of Zn2+ ions into the secondary structure of heteropoly tungstate: Catalytic efficiency for synthesis of glycerol carbonate from glycerol and urea
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Zinc exchanged heteropoly tungstate (ZnxTPA) catalysts were prepared and characterized by FT-IR, X-ray diffraction, Laser Raman spectroscopy, temperature programmed desorption of ammonia and pyridine adsorbed FT-IR spectroscopy. The activity of the catalysts was evaluated for the carbonylation of glycerol using urea as a carbonylating agent. ZnxTPA catalysts showed high activity for glycerol carbonate synthesis compared to the parent TPA. The activity of ZnxTPA catalysts depended on the number of Zn2+ ions in the secondary structure of heteropoly tungstate. Catalysts with partial exchange of Zn with the protons of TPA (Zn 1TPA) exhibited high activity towards glycerol carbonate synthesis. Exchange of protons of TPA with Zn2+ ions resulted in generation of Lewis acidic sites. The changes in surface and structural properties of Zn 1TPA catalysts with change in calcination temperature were also evaluated. The catalytic activities of ZnxTPA catalysts were explained based on the variation in their properties. Reaction conditions such as reaction temperature, catalyst weight and glycerol to urea ratio were also optimized. the Partner Organisations 2014.
- Jagadeeswaraiah,Kumar, Ch. Ramesh,Prasad, P.S. Sai,Lingaiah
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- Imidazolium-2-carboxylate as an efficient, expeditious and ecofriendly organocatalyst for glycerol carbonate synthesis
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An improved and greener approach towards the synthesis of glycerol carbonate, via transesterification, using l-n-butyl-3-methylimidazolium2- carboxylate as catalyst is described. The catalyst loading as low as 1% was sufficient to yield quantitative conve
- Naik, Prashant U.,Petitjean, Laetitia,Refes, Karima,Picquet, Michel,Plasseraud, Laurent
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- Transesterification of glycerol with dimethyl carbonate over calcined Ca-Al hydrocalumite
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A series of Ca-Al hydrocalumite with different Ca/Al ratios (1-6) were synthesized and used in the transesterification of glycerol with dimethyl carbonate (DMC) to glycerol carbonate (GC) under mild conditions. The calcined Ca-Al hydrocalumites were active with a selectivity toward GC that reached 97% at 93% conversion of glycerol over the sample with Ca/Al = 2 at 70 °C, 3 h, and DMC/glycerol = 3. The glycerol conversion depended mainly on the proportion of strong basic sites in the calcined Ca-Al catalysts. The Ca12Al14O33 phase in the calcined catalysts was stable, but CaO was lost in recycle experiments and thus brought deactivation.
- Zheng, Liping,Xia, Shuixin,Lu, Xiuyang,Hou, Zhaoyin
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- Catalytic performance of polymer-supported ionic liquids in the synthesis of glycerol carbonate from glycerol and urea
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Ionic liquids (ILs) immobilized onto a structurally modified Merrifield peptide resin (MPR) were prepared through the reaction of imidazole with alkoxylated MPR. Elemental analysis and scanning electron microscopy (SEM) observations showed that the immobilized IL groups were effectively incorporated on the support. The MPR-supported ILs (MPR-ILs) proved to be effective heterogeneous catalysts for the synthesis of glycerol carbonate (GC) from glycerol and urea. MPR-ILs with longer alkyl chain linkers and fewer sterically hindered counteranions resulted in higher conversion of glycerol. High temperature, high degree of vacuum and the presence of zinc oxide co-catalyst were favorable for glycerol conversion. The MPR-ILs could be reused in up to three consecutive runs without significant loss of their catalytic activity.
- Kim, Dong-Woo,Park, Moon-Seok,Selvaraj, Manickam,Park, Gyung-Ah,Lee, Sun-Do,Park, Dae-Won
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- Development of a trapezoidal MgO catalyst for highly-efficient transesterification of glycerol and dimethyl carbonate
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A series of micro-sized MgO catalysts with various morphologies have been prepared by varying the reaction temperature and stirring time during precipitation, and were investigated for the production of glycerol carbonate from the transesterification of glycerol with dimethyl carbonate. In contrast to other morphologies of MgO (e.g., rod-like, spherical, flower-like and nest-like), trapezoidal MgO demonstrated a superior performance with a yield of glycerol carbonate of more than 99%. Various techniques including N2 physical adsorption, XRD, CO2 chemical adsorption and EDS revealed that the unique catalytic activity of trapezoidal MgO was related to its lower specific surface area, bigger crystallite size, weaker surface basicity and fewer Mg atom vacancies compared to the other morphologies of MgO. The experimental conditions (e.g., the catalyst amount, solvent, reaction temperature and molar ratio between glycerol and dimethyl carbonate) were also found to play crucial roles in determining the yield of glycerol carbonate. Furthermore, CO2-TPD profiles and FT-IR spectra indicated that the weak surface basic sites occurring at 150 °C and the CO32- stretching vibration around 1448 cm-1 were responsible for the catalytic activity of the developed trapezoidal MgO in regeneration.
- Bai, Zongquan,Zheng, Yajun,Han, Weiwei,Ji, Yue,Yan, Tianlan,Tang, Ying,Chen, Gang,Zhang, Zhiping
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- Synthesis of glycerol carbonate by direct carbonylation of glycerol with CO2 over solid catalysts derived from Zn/Al/La and Zn/Al/La/M (M = Li, Mg and Zr) hydrotalcites
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Zn/Al/La and Zn/Al/La/M (M = Li, Mg, Zr) mixed oxides were obtained by calcination of hydrotalcite precursors and tested for glycerol carbonate (GC) synthesis from CO2 carbonylation. The results indicated the catalytic activity may be associated with the large specific surface area, the high surface content of Zn and the high binding energy of Zn atoms as well as the high density of moderately basic sites. The good result was obtained on the catalyst with a molar ratio of Zn:La:Al = 4:1:1 and, within a certain range, glycerol conversion and GC yield increase linearly upon the increase of the density of moderately basic sites. In addition, the catalytic activity was obviously improved upon introduction of Li, Mg and Zr. The effect of reaction parameters on the carbonylation of glycerol was also studied. The DRIFTS results suggest that the activated CO2 may be in the form of a bridged bidentate carbonate that inserts into zinc glycerolate to form an intermediate species of a seven-membered ring ester followed by intramolecular rearrangement to produce GC. Theoretical calculation results indicated that the seven-membered ring ester has good stability and the formation process happens spontaneously.
- Li, Hongguang,Jiao, Xi,Li, Lei,Zhao, Ning,Xiao, Fukui,Wei, Wei,Sun, Yuhan,Zhang, Bingsheng
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- Synthesis of glycerol carbonate from glycerol and dimethyl carbonate catalyzed by calcined silicates
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Several anhydrous silicates were prepared by calcination at 400?°C and utilized as solid base catalyst for synthesizing glycerol carbonate (GC) by transesterification of glycerol with dimethyl carbonate (DMC). Among them, calcined sodium silicate showed the best catalytic activity with glycerol conversion of 97.7%. Then, a series of sodium silicates calcined at different temperatures were characterized using TGA, Hammett indicator method, BET, XRD, FT-IR and FESEM. Effect of calcination temperature on their catalytic ability was carefully investigated, followed by a reaction optimization study. The basicity of sodium silicates calcined at different temperatures highly depended on calcination temperature; their catalytic ability was affected by their total basicity rather than by their BET surface area; and the increased amount of strong basic sites resulted in the formation of by-product which decreased the GC yield and GC selectivity. Sodium silicate calcined at 200?°C (Na2SiO3-200), which had the intermediate total basicity and relative low amount of strong basic sites, incurred the highest GC yield. The highest catalytic performance of Na2SiO3-200 was achieved under the condition that the 4:1 molar ratio of DMC to glycerol was reacted at 75?°C for 2.5?h. This catalyst could be reused five times without noticeable drop in catalytic activity.
- Wang, Song,Hao, Pengfei,Li, Sanxi,Zhang, Ailing,Guan, Yinyan,Zhang, Linnan
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- The investigation of thermal pyrolysis of glycerol carbonate derivatives by TG-FTIR
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Three new GC derivatives, carbonic acid bis-(2-oxo-[1,3]dioxolan-4-ylmethyl) ester (CABE), succinic acid bis-(2-oxo-[1,3]dioxolan-4-ylmethyl) ester (SABE) and terephthalic acid bis-(2-oxo-[1,3]dioxolan-4-ylmethyl) ester (TABE), were designed and synthesized. We investigated the thermal stability and the thermal pyrolysis of three compounds by TG-FTIR, and the bond dissociation energy was calculated to further demonstrate the decomposition process. The results showed that the three GC derivatives had one, two, three weight loss stages, respectively. Their initial decomposition temperature was as high as 200 °C, which means that the compounds have good thermal stability. 5% weight loss temperature was increased in the order of TABE > SABE > CABE. In thermal pyrolysis process, the C-C, C-O bonds of cyclic carbonate fractured preferentially, and then the C-O bonds nearby cyclic carbonate of SABE and TABE continued to fracture to produce linear ester in the form of fragment.
- Li, Rujuan,Liu, Jing,Tao, Hairong,Sun, Donglan,Xiao, Dagang,Liu, Chunjing
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- Direct Carbonation of Glycerol with CO2 Catalyzed by Metal Oxides
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Five metal oxides (ZnO, SnO2, Fe2O3, CeO2, La2O3) were produced by the sol–gel method and tested in the direct carbonation of glycerol with CO2. Initial tests with Fe2O3 showed that the best reaction condition was 180 °C, 150 bar, and 12 h. The other oxides were evaluated at these conditions and were all active to the formation of glycerol carbonate. Zinc oxide was the most active catalyst, with a yield of 8.1 % in the organic carbonate. The catalytic activity decreased upon washing and drying the ZnO catalyst between the runs. Nevertheless, the activity is maintained if the ZnO is washed and calcined at 450 °C between the runs. FTIR and TGA results indicated the formation of ZnCO3 as the main cause of catalyst deactivation, which may be decomposed upon calcination of the material. No appreciable leaching of Zn was observed, indicating a truly heterogeneous catalysis.
- Ozorio, Leonardo P.,Mota, Claudio J. A.
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- Synthesis of glycerol carbonate by transesterification of glycerol with dimethyl carbonate over MgAl mixed oxide catalysts
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A series of hydrotalcite-like layered double hydroxides (LDHx) with different Mg/Al atomic ratios (x = 2-6) were prepared by using the co-precipitation method. Further calcination yields mixed oxides with tunable basicity. The basicity of the calcined LDHx (LDOx) strongly depends on the Mg/Al ratio and the calcination temperature. The resulting LDOx materials were used as solid base catalysts and evaluated in the transesterification between glycerol and dimethyl carbonate without use of organic solvent. The correlation between the basic properties of the solid catalysts and the catalytic performance was investigated. The activity of the LDOx catalysts was demonstrated to be proportional to the surface density of basic sites. LDO2 calcined at 600 C exhibited maximum activity for the transesterification reaction. The beneficial effect of the optimum ratio of Mg/Al = 2 is related to its high total basicity. The LDO2 catalyst can be readily recycled while maintaining high catalytic activity and selectivity of glycerol carbonate.
- Liu, Peng,Derchi, Margherita,Hensen, Emiel J.M.
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- Halide aided synergistic ring opening mechanism of epoxides and their cycloaddition to CO2 using MCM-41-imidazolium bromide catalyst
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Imidazole was immobilized on MCM-41 using 3-chloropropyltriethoxysilane (CPTES) as the anchoring agent followed by alkylation with 1,2-dibromoethane at 110 C. The resulting catalyst was designated as MCM-41-Imi/Br. The catalyst was used for the synthesis of cyclic carbonates via cycloaddition of CO2 with several epoxides under solvent free condition. The use of MCM-41-Imi (without bromide ion) to catalyze the reaction led to the elucidation of the reaction mechanism involved in the synergistic catalysis. The catalyst was used in the cycloaddition of styrene oxide, epichlorohydrine, glycidol, allyl glycidyl ether and phenyl glycidyl ether. A high yield and excellent selectivity of cyclic carbonates were obtained under optimized conditions. The yields of the respective cyclic carbonates were 98.8% for styrene oxide, 97.0% for epichlorohydrin, 98.3% for glycidol, 97.5% for allyl glycidyl ether, 96.7% for phenyl glycidyl ether and 100% for 1,2-epoxyhexane.
- Adam, Farook,Appaturi, Jimmy Nelson,Ng, Eng-Poh
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- Catalytic Space Engineering of Porphyrin Metal–Organic Frameworks for Combined CO2 Capture and Conversion at a Low Concentration
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Porous porphyrin metal-organic frameworks (PMOFs) provide promising platforms for studying CO2 capture and conversion (C3) owing to their versatility in photoelectric, catalytic, and redox activities and porphyrin coordination chemistry. Herein, we report the C3 application of two PMOFs by engineering the coordination space through the introduction of two catalytic metalloporphyrins doped with rhodium or iridium, Rh-PMOF-1 and Ir-PMOF-1, both of which can serve as heterogeneous catalysts for the chemical fixation of CO2 into cyclic carbonates with yields of up to 99 %. Remarkably, the catalytic reactions can effectively proceed under low CO2 concentrations and high yields of 83 % and 73 % can be obtained under 5 % CO2 in the presence of Rh-PMOF-1 and Ir-PMOF-1, respectively. The synergistic effect of the metalloporphyrin ligand and the Zr6O8 cluster, in combination with the CO2 concentration effect from the pore space, might account for the excellent catalytic performance of Rh-PMOF-1 under low CO2 concentration. Recycling tests of Rh-PMOF-1 show negligible loss of catalytic activity after 10 runs.
- Liu, Jiewei,Fan, Yan-Zhong,Li, Xin,Xu, Yao-Wei,Zhang, Li,Su, Cheng-Yong
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- Glycidol: an Hydroxyl-Containing Epoxide Playing the Double Role of Substrate and Catalyst for CO2Cycloaddition Reactions
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Glycidol is converted into glycerol carbonate (GC) by coupling with CO2in the presence of tetrabutylammonium bromide (TBAB) under mild reaction conditions (T=60 °C, PCO2=1 MPa) in excellent yields (99 %) and short reaction time (t=3 h). The unusual reactivity of this substrate compared to other epoxides, such as propylene oxide, under the same reaction conditions is clearly related to the presence of a hydroxyl functionality on the oxirane ring. Density functional theory calculations (DFT) supported by1H NMR experiments reveal that the unique behavior of this substrate is a result of the formation of intermolecular hydrogen bonds into a dimeric structure, activating this molecule to nucleophilic attack, and allowing the formation of GC. Furthermore, the glycidol/TBAB catalytic system acts as an efficient organocatalyst for the cycloaddition of CO2to various oxiranes.
- Della Monica, Francesco,Buonerba, Antonio,Grassi, Alfonso,Capacchione, Carmine,Milione, Stefano
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- Zn(ii) assisted synthesis of porous salen as an efficient heterogeneous scaffold for capture and conversion of CO2
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We have designed a unique strategy to obtain a zinc-salen functionalized porous polymer (Zn@SBMMP) with high zinc content (15.3 wt%) by an easy one-step, cost effective and scalable process, which shows unprecedented catalytic efficiency in the CO2 fixation reaction via cycloaddition of CO2 with epoxides. We hypothesize that a high density of Zn-Schiff base/salen units present in the porous polymer network is responsible for the exceptionally high catalytic performance of Zn@SBMMP.
- Bhunia, Subhajit,Molla, Rostam Ali,Kumari, Vandana,Islam, Sk. Manirul,Bhaumik, Asim
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- Efficient bio-conversion of glycerol to glycerol carbonate catalyzed by lipase extracted from Aspergillus niger
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A biocatalytic synthesis of glycerol carbonate (GlyC), as an added-value product of renewable glycerol, has been developed using a catalytic route in which glycerol (Gly) was reacting with dimethyl carbonate (DMC) in the presence of lipase under solvent-free conditions. The enzyme screening indicated lipase from Aspergillus niger as the most efficient biocatalyst for the GlyC synthesis. After the optimization of the reaction conditions it was established that the best results corresponded to 12% (w/w) Aspergillus niger lipase, to a glycerol:DMC molar ratio of 1:10, to an incubation time of 4 h and to an incubation temperature of 60 °C. Consequently, the glycerol conversion was around 74%, the yield in GlyC of 59.3% and the selectivity to GlyC of 80.3%. Recycling experiments demonstrated that the biocatalyst can be successfully used for several reaction cycles (at least 4 times) and confirmed its very high stability under the reaction conditions.
- Tudorache, Madalina,Protesescu, Loredana,Coman, Simona,Parvulescu, Vasile I.
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- Synthesis of glycerol carbonate from urea and glycerol using polymer-supported metal containing ionic liquid catalysts
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Polystyrene-supported, metal containing imidazolium salt [PS-(Im) 2MX2] catalysts were prepared and characterized by various analytical methods, and their role in the synthesis of glycerol carbonate from glycerol and urea was investigated under mild conditions. Among different metal containing PS-(Im)2MBr2 catalysts, the yield of GC increased Cu 2ZnI2 catalyst, which showed a good balance of the acid-base properties, was the most active and selective catalyst; it was readily recoverable and reusable in the subsequent reaction cycles. Furthermore, the reaction pathway for the glycerolysis of urea was studied with the time-on-line analysis of the products via a combination of FT-IR spectroscopy and 13C NMR analysis. The effects of reaction parameters such as temperature, degree of vacuum, catalyst loading, and the ratio of reactants on the reactivity were also investigated to elucidate the reaction mechanism.
- Kim, Dong-Woo,Park, Kyung-Ah,Kim, Min-Ji,Kang, Dong-Heon,Yang, Jeong-Gyu,Park, Dae-Won
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- The value-added utilization of glycerol for the synthesis of glycerol carbonate catalyzed with a novel porous ZnO catalyst
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In the carbonylation reaction, a novel porous ZnO was prepared by a calcination method, and the raw material Zn glycerolate platelets were prepared via the glycerol approach, which could make use of a by-product of glycerol. To elucidate their composition, morphology, and properties, the resulting materials were characterized by FT-IR, XRD, SEM, BET, XPS, TPD and TG. The results showed that the catalyst was porous and irregularly shaped with appropriate acid and base properties; moreover, it displayed better catalytic performance for the synthesis of glycerol carbonate. The highest glycerol carbonate yield reached 85.97% of ZnO from zinc glycerolate under the optimal reaction conditions of 5.0 wt% of catalyst, 1:1.5 molar ratio of glycerol to urea and reacting at 140 °C for 6 h under 1 kPa. Comparing the three catalysts ZnO, zinc glycerolate and ZnO from zinc glycerolate, the maximum glycerol carbonate yield was 85.97% with the ZnO from zinc glycerolate as the catalyst under optimized operating conditions. Compared with the conventional ZnO, the as-prepared catalyst embodied in its porosity, acidity and basicity. The catalyst maintained excellent catalytic performance after 5 cycles with almost no loss of catalytic activity. This study revealed that ZnO from a zinc glycerolate catalyst is highly active, highly recyclable, remarkably stable, and environmental friendly for industrial applications. Overall, this new material overcomes the limitation of glycerol application and will have a good potential for industrial application.
- Zhang, Pingbo,Liu, Lihua,Fan, Mingming,Dong, Yuming,Jiang, Pingping
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- Reusable gypsum based catalyst for synthesis of glycerol carbonate from glycerol and urea
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In this study, the catalytic carbonylation of glycerol with urea in the presence of gypsum based heterogeneous catalyst is reported for the first time. Gypsum (CaSO4·2H2O) is one of the two calcium sulphate minerals found in nature a
- Zuhaimi, Nor Ain Syuhada,Indran, Vidhyaa Paroo,Deraman, Mohd Asyrak,Mudrikah, Nor Farihan,Maniam, Gaanty Pragas,Taufiq-Yap, Yun Hin,Ab Rahim, Mohd Hasbi
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- A highly efficient rod-like-CeO2-supported palladium catalyst for the oxidative carbonylation of glycerol to glycerol carbonate
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A rod-like-CeO2-supported Pd catalyst (Pd/CeO2-r) was prepared using two-step hydrothermal impregnation and used in the oxidative carbonylation of glycerol to produce glycerol carbonate. The characterization results showed that the Pd was highly dispersed on the surface of the CeO2-r, and metallic Pd was the main species in the catalyst. The Pd/CeO2-r exhibited good catalytic performance for the oxidative carbonylation of glycerol. Under optimized reaction conditions, the glycerol conversion and glycerol carbonate selectivity were 93% and 98%, respectively, and turnover frequency was 1240 h?1. However, because of the leaching of Pd and the growth of Pd particles, the catalyst was gradually deactivated throughout reuse.
- Wang, Ziyan,Guo, Shuo,Wang, Zhimiao,Li, Fang,Xue, Wei,Wang, Yanji
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- Synthesis of glycerol carbonate by transesterification of glycerol with urea over Zn/Al mixed oxide
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Reactions of glycerol carbonate using glycerol and urea have been carried out previously using ZnSO4 and ZnO catalysts, and high yields have been reported using ZnSO4 as catalyst. However, this salt is soluble in glycerol, and recycling of catalyst is difficult after the reaction. In this study, we prepared a mixed metal oxide catalyst using Zn and Al, and this catalyst consisted of a mixture of ZnO and ZnAl2O4. We confirmed the conversion of glycerol and the yield of glycerol carbonate of the amount of Al. As a result, we obtained a yield of 82.3% and a conversion of 82.7%. In addition we obtained high yield in recycling of catalyst. The yield of the glycerol carbonate increases with an increase of acid and base site of catalysts and the highest catalytic activity was obtained when acid/base ratio was approx. 1. From this result, we may conclude that the acid and base site density and ratio of catalysts were very important parameters in the synthesis of glycerol carbonate from urea and glycerol.
- Ryu, Young Bok,Baek, Jae Ho,Kim, Yangdo,Lee, Man Sig
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- In situ synthesis of pyridinium-based ionic porous organic polymers with hydroxide anions and pyridinyl radicals for halogen-free catalytic fixation of atmospheric CO2
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Pyridinium-based ionic porous organic polymers (Py-iPOPs) were constructed from newly designed acetonitrile-functionalized ionic liquids and multi-carbaldehyde monomers by base-catalyzed Knoevenagel condensation. The obtained Py-iPOPs having in situ forme
- Liu, Ke,Xu, Zixuan,Huang, He,Zhang, Yadong,Liu, Yan,Qiu, Zhiheng,Tong, Minman,Long, Zhouyang,Chen, Guojian
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supporting information
p. 136 - 141
(2022/01/22)
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- Quaternization-induced catalyst-free synthesis of viologen-linked ionic polyacetylenes towards heterogeneous catalytic CO2 fixation
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In this work, we reported a facile catalyst-free and initiator-free strategy to fabricate a new class of viologen-linked ionic polyacetylenes (denoted as VIPAs) that can achieve simultaneous ionization and polymerization in one-pot and one-step. To our surprise, the ionic polymers VIPA-X (X = Br or Cl) were directly synthesized by quaternization-induced in situ polymerization from commercially available 4,4′-bipyridine with propargyl bromide or propargyl chloride. It was found that reaction temperatures have a remarkable influence on the synthesis of VIPAs, achieving the transformation from soluble oligomers to insoluble highly cross-linked polymers by adjusting the temperatures from 30 °C to 100 °C. At a higher temperature of 100 °C, the obtained highly cross-linked ionic polymers VIPA-Br and VIPA-Cl were insoluble in both hot water and even dimethyl sulfoxide (DMSO). By virtue of abundant halogen anions and the absorbed H-bonded water, both VIPA-Br and VIPA-Cl were employed as efficient heterogeneous catalysts for the conversion of CO2 with various epoxides into cyclic carbonates at atmospheric pressure and low temperatures. In particular, the catalytic activities of VIPA-Br for the conversion of various epoxides are much better than those of VIPA-Cl at low temperatures, which should be attributed to the higher nucleophilicity and better leaving ability of the Br-anion than those of the Cl-anion. The present work affords a succinct catalyst-free strategy to construct more task-specific ionic polyacetylenes by quaternization-induced polymerization of multi-N-heterocycle monomers and propargyl halides towards diverse applications.
- Chen, Guojian,Huang, He,Liu, Ke,Long, Zhouyang,Tong, Minman,Xu, Zixuan,Zhang, Yadong
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supporting information
p. 5540 - 5549
(2022/04/09)
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- A Zn(ii)-functionalized COF as a recyclable catalyst for the sustainable synthesis of cyclic carbonates and cyclic carbamates from atmospheric CO2
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A simple covalent organic framework (COF) bearing β-ketoenamine units as a potential heterogeneous ligand for ZnII-catalyzed fixation and transformation of CO2 into value-added chemicals is reported. Catalytic investigations convincingly demonstrated that the ZnII-functionalized covalent organic framework (Zn@TpTta) exhibits perfect catalytic activity in the fixation of CO2 for diverse epoxides with various substituents under sustainable conditions. A variety of terminal epoxides and slightly more complicated disubstituted epoxides were transformed into the corresponding cyclic carbonates with satisfactory to excellent yields (i.e., 69 to 99% yield) upon exposure to CO2 (1 atm) under solvent-free conditions (sustainable approach). On the other hand, this ZnII-loaded covalent organic framework also displayed excellent performance in facilitating atmospheric cyclizative CO2 capture, which led to the formation of diverse cyclic carbamates (i.e., 61 to 94% yield) from unsaturated amine systems using N-iodosuccinimide (NIS) as an iodinating agent and PEG-400 as a biodegradable and green polymeric solvent under base-free conditions (sustainable approach). The newly synthesized COF-based catalyst, namely, Zn@TpTta, has been completely characterized by SEM (scanning electron microscopy), EDX (energy dispersive X-ray analysis), HRTEM (high-resolution transmission electron microscopy), BET (Brunauer-Emmett-Teller), PXRD (powder X-ray diffraction), XPS (X-ray photoelectron spectroscopy), ICP (inductively coupled plasma), etc. More intriguingly, the catalytic system could be recycled over five times without a noticeable loss of catalytic performance for both reactions. This study opens an avenue for the Zn(ii) embedded COF as a promising platform for regulating regioselectivity.
- Ghosh, Swarbhanu,Islam, Sk. Manirul,Sarkar, Somnath
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p. 1707 - 1722
(2022/03/02)
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- Tuneable transesterification of glycerol with dimethyl carbonate for synthesis of glycerol carbonate and glycidol on MnO2 nanorods and efficacy of different polymorphs
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Bioglycerol must be valorized to make biodiesel competitive vis-à-vis petro-diesel price. Glycerol carbonate is a sustainable chemical used by many industries. Various routes are reported but there exists a scope to develop better catalytic routes for selective synthesis of glycerol carbonate. Different polymorphs of MnO2 were explored as catalyst for the first time in the synthesis of glycerol carbonate by transesterification of glycerol with dimethyl carbonate under solvent-free conditions. The effect of microwave condition versus conventional heating was compared vis-a-vis conversion of glycerol, selectivity of glycerol carbonate and glycidol. Microwave heating (80 °C) was advantageous over conventional heating (120 °C). Different mesoporous polymorphs of MnO2 were prepared by hydrothermal synthesis and the activity of each polymorph was screened for transesterification reaction of glycerol. All MnO2 polymorphs were completely characterized. δ-MnO2 was the most active, selective, robust and recyclable catalyst. A kinetic model was developed. The overall process is green and sustainable.
- Deshmukh, Gunjan P.,Yadav, Ganapati D.
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- Photoinduced synergistic catalysis on Zn single-atom-loaded hierarchical porous carbon for highly efficient CO2cycloaddition conversion
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The use of solar energy to drive efficient CO2cycloaddition conversion under mild reaction conditions is highly desired but remains a significant challenge. In this communication, a Zn single-atom-loaded N-doped carbon (Zn SA-NC) is facilely synthesizedviadirect pyrolysis of N-rich energetic MOFs. Because of a multiple light reflection effect, the obtained Zn SA-NC with a hierarchical porous structure shows an ultrahigh light-harvesting efficiency of >97% in a broadband range (250-2500 nm). The photogenerated electrons and photothermal effects can synergistically catalyze CO2cycloaddition reaction with Zn-N4as the main active sites. When faced with various epoxides, Zn SA-NC shows high catalytic activity with almost complete CO2cycloaddition conversion yields. It is assumed that this study has provided some unprecedented findings for the future design and application of single-atom catalysts in photoinduced CO2cycloaddition catalysis or other catalytic reactions.
- Gong, Lin,Sun, Ji,Liu, Yousong,Yang, Guangcheng
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supporting information
p. 21689 - 21694
(2021/10/12)
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- Rosin-based porous heterogeneous catalyst functionalized with hydroxyl groups and triazole groups for CO2 chemical conversion under atmospheric pressure condition
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Development of efficient, green and recyclable heterogeneous catalysts for the chemical conversion of CO2 into cyclic carbonates with excellent yields under atmospheric pressure condition is still a very challenging task. Herein, a class of biomass-derived hyper-cross-linked porous heterogeneous catalysts MPAc-Br and MPAc-OH-Br, based on easily available and sustainable rosin, was synthesized by Friedel–Crafts polymerization and the further N-alkylation of triazole groups. Compared with MPAc-Br, the bifunctional catalyst MPAc-OH-Br (bearing triazole IL groups and -OH groups) exhibited higher catalytic activity for direct chemical conversion of CO2 into cyclic carbonates (up to 99% yields) under metal-, solvent-free and atmospheric pressure conditions. The rosin-based porous molecular structure and bifunctional groups on the surface of MPAc-OH-Br played a very important role in the promoting the cycloaddition of CO2 with epoxides under the optimal conditions. Furthermore, MPAc-OH-Br exhibited good stability and reusability (96% yield after 10 recycles).
- Gao, Jinbin,Lai, Shilin,Xiong, Xingquan
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- Mono- And Dinuclear Asymmetric Aluminum Guanidinates for the Catalytic CO2Fixation into Cyclic Carbonates
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A set of trisubstituted guanidine ligands L1H2-L4H2 with general formula (iPrHN)2CNR (R = Ph (L1H2), R = 2,4,6-Me3C6H2(L2H2), R = p-BrC6H4(L3H2), R = (C5H4)Fe(C5H5), Fc (L4H2)) was employed to synthesize a family of mono- and dinuclear asymmetric methyl a
- Rios Yepes, Yersica,Mesías-Salazar, ángela,Becerra, Alexandra,Daniliuc, Constantin G.,Ramos, Alberto,Fernández-Galán, Rafael,Rodríguez-Diéguez, Antonio,Anti?olo, Antonio,Carrillo-Hermosilla, Fernando,Rojas, René S.
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supporting information
p. 2859 - 2869
(2021/08/30)
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- Catalytic, Kinetic, and Mechanistic Insights into the Fixation of CO2 with Epoxides Catalyzed by Phenol-Functionalized Phosphonium Salts
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A series of hydroxy-functionalized phosphonium salts were studied as bifunctional catalysts for the conversion of CO2 with epoxides under mild and solvent-free conditions. The reaction in the presence of a phenol-based phosphonium iodide proceeded via a first order rection kinetic with respect to the substrate. Notably, in contrast to the aliphatic analogue, the phenol-based catalyst showed no product inhibition. The temperature dependence of the reaction rate was investigated, and the activation energy for the model reaction was determined from an Arrhenius-plot (Ea=39.6 kJ mol?1). The substrate scope was also evaluated. Under the optimized reaction conditions, 20 terminal epoxides were converted at room temperature to the corresponding cyclic carbonates, which were isolated in yields up to 99 %. The reaction is easily scalable and was performed on a scale up to 50 g substrate. Moreover, this method was applied in the synthesis of the antitussive agent dropropizine starting from epichlorohydrin and phenylpiperazine. Furthermore, DFT calculations were performed to rationalize the mechanism and the high efficiency of the phenol-based phosphonium iodide catalyst. The calculation confirmed the activation of the epoxide via hydrogen bonding for the iodide salt, which facilitates the ring-opening step. Notably, the effective Gibbs energy barrier regarding this step is 97 kJ mol?1 for the bromide and 72 kJ mol?1 for the iodide salt, which explains the difference in activity.
- Hu, Yuya,Wei, Zhihong,Frey, Anna,Kubis, Christoph,Ren, Chang-Yue,Spannenberg, Anke,Jiao, Haijun,Werner, Thomas
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p. 363 - 372
(2020/11/30)
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- Method for preparing cyclic carbonate by immobilizing CO2 under catalysis of organic boric acid
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The invention discloses a synthesis method for synergistically catalyzing carbon dioxide immobilization through weak Lewis acid phenylboronic acid and tetrabutylammonium bromide. According to the method, CO2 is immobilized by epoxide, and a cyclic carbonate product is generated. The method comprises the following step: under the concerted catalysis of phenylboronic acid and tetrabutylammonium bromide, performing reaction on epoxide as shown in a formula IV, a formula V or a formula VI and carbon dioxide to respectively obtain a cyclic carbonate product as shown in a formula I, a formula II or a formula III. According to the method, raw materials are convenient and easy to obtain, reaction conditions are mild, operation is easy and convenient, and the yield can reach 97%.
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Paragraph 0113-0118
(2021/06/22)
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- Cycloaddition of carbon dioxide and epoxides catalyzed by rare earth metal complexes bearing a Trost ligand
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A series of rare earth metal complexes (Sm (1), Eu (2), Y (3), Yb (4), and Lu (5)) based on Trost ligands were synthesized and well characterized, and catalyzed the cycloaddition of carbon dioxide and epoxides successfully. The combination of 1 mol% Sm-based complex1with 2 mol% tetrabutylammonium bromide (TBAB) was proved to be the optimal catalyst system for the formation of the monosubstituted cyclic carbonate at 70 °C under the atmospheric pressure. While for the more challenging disubstituted epoxides, the adduct cyclic carbonates were successfully obtained when the pressure of CO2was elevated to 0.7 MPa.
- Cheng, Jun,Lu, Chengrong,Zhao, Bei
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p. 13096 - 13103
(2021/08/04)
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- The catalytic system ‘Rhodamine B/additive’ for the chemical fixation of CO2
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The catalytic system ‘Rhodamine B/additive’ was introduced to promote the CO2 reactions. We synthesized various cyclic carbonates in good to excellent yields under the catalysis of rhodamine B and TBAB. A variety of 2-oxazolidinone derivatives were obtained in the presence of rhodamine B and DBU.
- Wu, Feng-tian,Wu, Ling,Cui, Chun-na
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- Lanthanum nanocluster/ZIF-8 for boosting catalytic CO2/glycerol conversion using MgCO3as a dehydrating agent
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A lanthanum-modified zeolitic imidazolate framework (La/ZIF-8) was developed to produce glycerol carbonate using CO2and glycerol as raw materials. La/ZIF-8 provides a high catalytic glycerol conversion efficiency owing to its surface-attached nanoclusters of La2O3, which can be viewed as La3+-O2?pairs that strengthen the Lewis basicity and acidity, and the large specific surface area of ZIF-8. The catalytic glycerol conversion and the yield of glycerol carbonate were 46.5% and 35.3%, respectively, using CH3CN as a dehydrating agent. With increase in the amount of CH3CN, the water molecules could react with CH3CN to reduce the selectivity. When an inorganic dehydrating agent, MgCO3, was used to physically adsorb and remove water molecules in the reaction, the selectivity of the reaction could be increased to over 95%, which is the highest ever reported. Reaction kinetics analysis also revealed that the activation energy of using MgCO3(5.4 kJ mol?1) as a dehydrating agent is lower than that using CH3CN (7.8 kJ mol?1). Moreover, the La/ZIF-8 could be recycled and reused at least three times with high catalytic performance. This study provides an effective material with dual Lewis basicity and acidity for CO2/glycerol conversion and significantly improves the catalytic performance using an inorganic dehydrating agent.
- Hu, Chechia,Chang, Chien-Wei,Yoshida, Masaaki,Wang, Ke-Hsuan
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p. 7048 - 7058
(2021/03/29)
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- Solar energy-controlled shape selective synthesis of zinc oxide nanomaterials and its catalytic application in synthesis of glycerol carbonate
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In this study, we have synthesized shape selective zinc oxide (ZnO) nanoflower using solar energy and naturally accessible aromatic amino acids like tryptophan, tyrosine and phenylalanine as a photo capping agents. This synthesized material has been characterized by various characterization techniques such as XRD, FE-SEM, EDX, UV–Vis and FTIR. The ZnO nanoflower synthesized using solar energy and photo capping agents exhibited excellent catalytic activity after calcination for the synthesis of glycerol carbonate via urea glycerolysis as compared to the conventional process owing to its shape selective morphology. Further, high resolution XPS studies were performed to explore the valence states and effectiveness of surface engineering of the ZnO catalyst. Such a unique technique of ZnO nanoflowers synthesis represents a novel and environmentally benign route for synthesis of shape selective metal oxide nanoparticles as well as derived nanomaterial after calcination showed excellent activity and potential recyclability for the conversion of waste into valuable products. After calcination ZnO nanomaterials shows 67% yield in the synthesis of glycerol carbonate at 140 ?°C in 4 ?h, at the end a catalytic reaction mechanism was proposed.
- Ahire, Jayendra,Bhanage, Bhalchandra M.
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- METHOD FOR PRODUCING CARBONATE DERIVATIVE
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The objective of the present invention is to provide a method for producing a polycarbonate safely and efficiently even without using a base. The method for producing a carbonate derivative according to the present invention is characterized in comprising the step of irradiating a high energy light to a composition comprising the halogenated methane and the hydroxy group-containing compound in the presence of oxygen, wherein a molar ratio of a total usage amount of the hydroxy group-containing compound to 1 mole of the halogenated methane is 0.05 or more.
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Paragraph 0142-0144
(2022/01/04)
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- One-pot Fixation of CO2 into Glycerol Carbonate using Ion-Exchanged Amberlite Resin Beads as Efficient Metal-free Heterogeneous Catalysts
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The one-pot synthesis of glycerol carbonate from carbon dioxide and glycerol was achieved using ion-exchanged Amberlite resin beads as metal-free heterogeneous catalysts. Two commercially available Amberlite resin beads consisting of polystyrene cross-linked with divinylbenzene and functionalized with either trimethyl ammonium chloride (IRA-900) or dimethyl ethanol ammonium chloride (IRA-910) groups were used as starting materials to prepare the catalysts. These polymeric beads were transformed into their iodide (Amb-900-I, Amb-OH-910-I) or hydroxide (Amb-900-OH and Amb-OH-910-OH) counterparts through straightforward ion-exchange reactions. First, the two resin bead catalysts in hydroxide form were tested in the base-catalyzed transcarbonation reaction of glycerol with propylene carbonate. Both resin bead catalysts were more active compared to benchmark basic catalysts as hydrotalcites and attained 80 % yield of glycerol carbonate over Amb-OH-910-OH after 2 h at 115 °C, employing a 4 : 1 ratio between propylene carbonate and glycerol. Then, the one-pot reaction of CO2, glycerol and propylene oxide to produce propylene carbonate, glycerol carbonate and propylene glycol was investigated as the main target of this study. The reaction involves two steps: the reaction of propylene oxide with CO2 yielding propylene carbonate, and the transcarbonation of the formed cyclic carbonate with glycerol. Amb-900-I, Amb-OH-910-I, Amb-OH-910-OH and combinations of the latter two were employed as catalysts. Although Amb-OH-910-I alone is poorly active in the transcarbonation reaction, it showed the highest catalytic activity in the one-pot cascade reaction, surprisingly surpassing the performance of the Amb-OH-910-I/Amb-OH-910-OH mixtures and reaching high yields of glycerol carbonate (81 %, 115 °C, 4 h). These findings led to proposing a mechanism for the one-pot reaction using the Amb-OH-910-I catalyst. The bead format led to easy recovery of the catalyst, which displayed good reusability in consecutive runs.
- Alassmy, Yasser A.,Paalman, Patrick J.,Pescarmona, Paolo P.
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p. 475 - 486
(2020/10/29)
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- Investigation of glycerolysis of urea over various ZnMeO (Me = Co, Cr, and Fe) mixed oxide catalysts
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In this study, we investigated the glycerolysis of urea over various ZnMeO (Me = Co, Cr, and Fe) mixed oxide catalysts. ZnMeO mixed oxide catalysts were prepared by a co-precipitation method for two Zn/Me ratios, resulting in Zn-rich mixed oxide (Zn2MeO) and Zn-poor mixed oxide (ZnMe2O). In the glycerolysis of urea, the Zn2MeO catalysts exhibited higher glycerol conversion and glycerol carbonate yields than the ZnMe2O catalysts due to the predominance of homogeneous catalysis through Zn isocyanate (NCO) complexes from the Zn2MeO catalysts. Specifically, Zn2CrO was the best catalyst, with the highest yield of glycerol carbonate. Fourier transform infrared (FT-IR) and thermogravimetric analysis (TGA) results of the spent catalysts clearly demonstrated the dominant formation of a solid Zn NCO complex over the spent Zn2CrO catalyst, a unique feature indicating that the better catalytic performance of Zn2CrO was due to the additional heterogeneous reaction route through the solid Zn NCO complex.
- Nguyen-Phu, Huy,Do, Lien Thi,Shin, Eun Woo
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- Preparation of mesoporous CaO-ZrO2 catalysts without template for the continuous synthesis of glycerol carbonate in a fixed-bed reactor
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Recently, transformation of glycerol into glycerol carbonate (GLC) has been of critical importance. Although traditional Ca-based catalysts present high activity for the GLC synthesis, their industrial applications are hindered by the leaching of Ca2+. Here, a series of mesoporous CaO-ZrO2 with high surface area were obtained without template. CO2 temperature-programmed desorption displayed that the basic properties of the catalysts can be controlled by the content of Ca dopant. Importantly, Ca2+ can be introduced into t-ZrO2 lattice, resulting in the formation of a solid solution structure. Based on systematic experiments, a correlation between their basic properties and catalytic behavior was explained. Under the optimized conditions, the catalyst with a certain ratio of Ca: Zr = 0.6: 1 showed an excellent performance with a 97% glycerol conversion and a 93% selectivity of GLC. Furthermore, the solid solution structure rendered this catalyst high resistance to reactant flushing in a fixed-bed, without leaching of active sites.
- Zhang, Xuelan,Wei, Shuwei,Zhao, Xueying,Chen, Zheng,Wu, Hongwei,Rong, Ping,Sun, Yu,Li, Ya,Yu, Hao,Wang, Dengfeng
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- Multi-active-center ionic liquid, preparation method and method for catalytically synthesizing cyclic carbonate by using multi-active-center ionic liquid
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The invention relates to a novel multi-active-center ionic liquid, the structural formula of which is shown in the specification, in the formula, n is equal to 1, 2 or 3. The invention also provides amethod for catalytically synthesizing cyclic carbonate by using the ionic liquid. The invention solves the problems of low catalyst performance, harsh reaction conditions and use of an organic solvent or a cocatalyst in the existing method for synthesizing cyclic carbonate by using CO2 and an epoxy compound, and uses a novel multi-active center ionic liquid as a catalyst to catalyze the epoxy compound and CO2 to carry out cycloaddition reaction at the pressure of 0.1-0.5 MPa and the temperature of 30-80 DEG C so as to generate cyclic carbonate. The highest yield can reach 98.5%.
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Paragraph 0037-0071
(2020/11/23)
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- Lignin modified by deep eutectic solvents as green, reusable, and bio-based catalysts for efficient chemical fixation of CO2
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Lignin is a biodegradable, abundant and renewable natural polymer on earth. In this study, deep eutectic solvents (DESs)-modified lignin heterogeneous catalysts were prepared for the first time via a facile acid-base interaction between choline chloride (
- Xiong, Xingquan,Zhang, Hui,Lai, Shi Lin,Gao, Jinbin,Gao, Lizhu
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- Scalable, Durable, and Recyclable Metal-Free Catalysts for Highly Efficient Conversion of CO2 to Cyclic Carbonates
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A series of highly active organoboron catalysts for the coupling of CO2 and epoxides with the advantages of scalable preparation, thermostability, and recyclability is reported. The metal-free catalysts show high reactivity towards a wide scope of cyclic carbonates (14 examples) and can withstand a high temperature up to 150 °C. Compared with the current metal-free catalytic systems that use mol % catalyst loading, the catalytic capacity of the catalyst described herein can be enhanced by three orders of magnitude (epoxide/cat.=200 000/1, mole ratio) in the presence of a cocatalyst. This feature greatly narrows the gap between metal-free catalysts and state-of-the-art metallic systems. An intramolecular cooperative mechanism is proposed and certified on the basis of investigations on crystal structures, structure–performance relationships, kinetic studies, and key reaction intermediates.
- Li, Bo,Wu, Guang-Peng,Xie, Rui,Yang, Guan-Wen,Yang, Li,Zhang, Yao-Yao
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supporting information
p. 23291 - 23298
(2020/10/19)
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- Synthesis of Ionic Liquids as Novel Nanocatalysts for Fixation of Carbon Dioxide with Epoxides by Using a Carbon Dioxide Balloon
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Abstract: In the present study, the nanocatalyst of imidazolium based ionic liquids (ILs) is synthesized for the fixation of carbon dioxide (CO2) under moderate conditions by utilizing a balloon of CO2 with commercially available epoxides. IL incorporated porous dendritic fibrous nanosilica (DFNS) catalyst (IL/DFNS) was designed and synthesized. The synthesized catalyst was characterized using N2 absorption desorption isotherm, XPS, SEM, EDX, TGA, HR-TEM, and AFM. For cyclic carbonate, an environmental friendly catalyst of porous IL/DFNS indicate highly impressive catalytic efficiency from CO2 through CO2 fixation and epoxides under mild condition. Attendance of polar hydroxyl and anion exchange nature groups of IL frame work to high surface area is known as the main aspect to be reliable for elevated catalytic efficiency and also advance in stability of catalyst and providing a proper recyclability. Graphic Abstract: [Figure not available: see fulltext.].
- Zhang, Pu,Zhiani, Rahele
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p. 2254 - 2266
(2020/02/18)
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- NNC-Scorpionate Zirconium-Based Bicomponent Systems for the Efficient CO2Fixation into a Variety of Cyclic Carbonates
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Two new derivatives of the bis(3,5-dimethylpyrazol-1-yl)methane modified by introduction of organosilyl groups on the central carbon atom, one of which bearing a chiral fragment, have been easily prepared. We verified the potential utility of these compou
- Fernández-Baeza, Juan,Garcés, Andrés,Lara-Sánchez, Agustín,Martínez-Ferrer, Jaime,Navarro, Marta,Rodríguez, Ana M.,Sánchez-Barba, Luis F.,Sobrino, Sonia
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supporting information
p. 12422 - 12430
(2020/09/15)
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- Organocatalytic carbon dioxide fixation to epoxides by perfluorinated 1,3,5-triols catalysts
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In order to improve epoxides conversion to carbonates by fixation of CO2 a new type of perfluorinated triol catalysts was developed. These simple acyclic scaffolds of enhanced acidity are efficient for catalysis through selective H-bonding acti
- Quintard, Adrien,Rodriguez, Jean,Sperandio, Céline
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supporting information
p. 2637 - 2640
(2020/04/17)
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- Aluminum complexes with new non-symmetric ferrocenyl amidine ligands and their application in CO2 transformation into cyclic carbonates
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A set of alkyl aluminum complexes supported by non-symmetric ferrocenyl amidine ligands were used as catalysts for the preparation of cyclic carbonates from epoxides and carbon dioxide using Bu4NI as a co-catalyst. A modified method for the synthesis of aminoferrocene allowed us to obtain this precursor in quantitative yield. Treatment of aminoferrocene with the corresponding acetimidoyl chloride afforded the desired ferrocenyl amidine ligands L1H, (E)-N-(2,6-diisopropylphenyl)-N'-(ferrocenyl)acetimidamide, and L2H, (E)-N-(2,6-dimethylphenyl)-N'-(ferrocenyl)acetimidamide. The reaction of these ligands with 1.0 or 0.5 equiv. of AlMe3 led to the synthesis of aminoferrocene based aluminum complexes ((L1)AlMe2 (1), (L2)AlMe2 (2), (L1)2AlMe (3), and (L2)2AlMe (4)) in excellent yields, which were characterized by spectroscopic and X-ray diffraction methods. In addition, we have studied their electrochemical properties and complex 1 was found to be the most active catalyst for the formation of cyclic carbonates 6a-j from their corresponding epoxides 5a-j and CO2.
- Rios Yepes, Yersica,Martínez, Javier,Rangel Sánchez, Hiram,Quintero, Celso,Ortega-Alfaro, M. Carmen,López-Cortés, José G.,Daniliuc, Constantin G.,Anti?olo, Antonio,Ramos, Alberto,Rojas, René S.
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supporting information
p. 1124 - 1134
(2020/02/04)
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- Efficient Conversion of Epoxides into Carbonates with CO 2 and a Single Organocatalyst: Laboratory and Kilogram-Scale Experiments
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Cheap and readily available 2-aminopyridine and related compounds can be used as organocatalysts for the conversion of epoxides into cyclic carbonates. This reaction gives high conversions under solvent-free conditions and is amenable to a kilogram-scale
- Azzouz, Rabah,Bischoff, Laurent,Contreras Moreno, Viviana,Derrouiche, Salim,Estel, Lionel,Herasme-Grullon, Clara,Ledoux, Alain,Levacher, Vincent,Marsais, Francis
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supporting information
p. 183 - 188
(2020/01/23)
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- Plasma-Assisted Immobilization of a Phosphonium Salt and Its Use as a Catalyst in the Valorization of CO2
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The first plasma-assisted immobilization of an organocatalyst, namely a bifunctional phosphonium salt in an amorphous hydrogenated carbon coating, is reported. This method makes the requirement for prefunctionalized supports redundant. The immobilized catalyst was characterized by solid-state 13C and 31P NMR spectroscopy, SEM, and energy-dispersive X-ray spectroscopy. The immobilized catalyst (1 mol %) was employed in the synthesis of cyclic carbonates from epoxides and CO2. Notably, the efficiency of the plasma-treated catalyst on SiO2 was higher than those of the SiO2 support impregnated with the catalyst and even the homogeneous counterpart. After optimization of the reaction conditions, 13 terminal and four internal epoxides were converted with CO2 to the respective cyclic carbonates in yields of up to 99 %. Furthermore, the possibility to recycle the immobilized catalyst was evaluated. Even though the catalyst could be reused, the yields gradually decreased from the third run. However, this is the first example of the recycling of a plasma-immobilized catalyst, which opens new possibilities in the recovery and reuse of catalysts.
- Brüser, Volker,Epping, Jan Dirk,Frank, Marcus,Hu, Yuya,Longwitz, Lars,Peglow, Sandra,Werner, Thomas
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- A non-metal Acen-H catalyst for the chemical fixation of CO2 into cyclic carbonates under solvent- and halide-free mild reaction conditions
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A metal-free Acen-H catalyst was effectively synthesized by a single step reflux method and successfully tested for the cycloaddition of CO2 with epoxides to synthesize cyclic carbonates. The Acen-H catalyst exhibited high activity and selectivity for the cycloaddition reaction in the absence of co-catalysts (halides) and solvents at mild reaction conditions of a reaction temperature of 110 °C and a reaction pressure of 1 MPa. Under the optimized reaction conditions, some of the epoxides were successfully converted into corresponding cyclic carbonates with a highest yield of ~98.5%. The composition and structure of the homogeneous catalyst was then systematically evaluated and the reaction kinetics and a plausible reaction mechanism for the cycloaddition of CO2 with epoxides were proposed. The density functional theory (DFT) calculation provided a corroborated elucidation for the proposed mechanism. The catalytic activity of the Acen-H catalyst was found to be originated from the active hydrogen bond donors (-O-H, =N---H) and imino groups present (-N=) in it, which played a synergistic role in the adsorption and activation of reactants as confirmed by the DFT studies. The structural characteristics of the catalyst was found to be crucial for the cycloaddition of CO2 with epoxides.
- Chen, Shiyu,Jia, Qingming,Liu, Yi,Pudukudy, Manoj,Shan, Shaoyun,Wang, Junya,Yue, Zhongxiao,Zhao, Wenbo
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- Broadening the Scope of Steroidal Scaffolds: The Umpolung of a Bis-Primary Amine Precatalyst for the Insertion of CO2into Epoxides
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A cholic acid-based bis-primary amine is capable of promoting the insertion of CO2 into epoxides with the cooperative aid of an iodide anion. This framework is transformed in situ into a bis-carbamic acid. The latter is the active catalytic species, opera
- Concellón, Carmen,Del Amo, Vicente,Fanjul-Mosteirín, Noé,Martín, Judith,Valdés, Carlos
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supporting information
p. 6988 - 6992
(2020/09/12)
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- Calcium carbide as a dehydrating agent for the synthesis of carbamates, glycerol carbonate, and cyclic carbonates from carbon dioxide
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Carbon dioxide (CO2) is a nontoxic and inexpensive C1 building block, which can be used for the synthesis of valuable chemicals such as aromatic carbamates from anilines and methanol (MeOH), glycerol carbonate from glycerol, and cyclic carbonates from diols. However, these reactions generate water as the byproduct and suffer from thermodynamic limits, which lead to low yields. Calcium carbide (CaC2) is a renewable chemical, which can be recycled from calcium that is abundant in the Earth's crust. Furthermore, CaC2 rapidly reacts with water. In this work, we used CaC2 as a dehydrating agent for the direct synthesis of carbamates (including polyurethane precursors) from amines, CO2, and MeOH. All reagents were commercially available. In addition, CaC2 was employed for the synthesis of glycerol carbonate from glycerol and CO2 with a zinc catalyst and N-donor ligand. A similar protocol was applied to synthesize cyclic carbonates from diols and CO2.
- Choi, Jun-Chul,Fujitani, Tadahiro,Fukaya, Norihisa,Lin, Xiao-Tao,Sato, Kazuhiko,Yuan, Hao-Yu,Zhang, Qiao
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supporting information
p. 4231 - 4239
(2020/10/02)
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- Thermodynamic favorable CO2 conversion via vicinal diols and propargylic alcohols: A metal-free catalytic method
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Organocatalysis represents a promising field in chemical fixation of CO2. Herein, a facile metal-free strategy was reported for the one-pot preparation of cyclic carbonates and α-hydroxy ketones from vicinal diols, propargylic alcohols and CO2. Wide scope of vicinal diols and propargylic alcohols was demonstrated to be efficient under the DBU-catalyzed conditions. A plausible mechanism was proposed, which included detailed main and side reactions under the metal-free conditions.
- Han, Li-Hua,Li, Jing-Yuan,Song, Qing-Wen,Zhang, Kan,Zhang, Qian-Xia,Sun, Xiao-Fang,Liu, Ping
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supporting information
p. 341 - 344
(2019/07/04)
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- Solvent-Free Production of Glycerol Carbonate from Bioglycerol with Urea Over Nanostructured Promoted SnO2 Catalysts
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Abstract: In this study nanostructured MoO3 and WO3 promoted SnO2 solid acid catalysts were explored for the production of glycerol carbonate via carbonylation of bioglycerol with urea. The investigated reference SnO2 and promoted catalysts were synthesized by fusion and wet-impregnation methods, respectively. The physicochemical properties of the prepared catalysts were thoroughly analyzed by XRD, Raman, BET surface area, TEM, FTIR, pyridine adsorbed FTIR, NH3-TPD, and XPS techniques. It was found from the characterization studies that integration of SnO2 with MoO3 and WO3 promoters leads to remarkable structural, textural, and acidic properties. Especially, a high quantity of acidic sites were observed over the MoO3/SnO2 catalyst (~ 81.45?μmol?g?1) followed by WO3/SnO2 (61.81?μmol?g?1) and pure SnO2 (46.47?μmol?g?1), which played a key role in the carbonylation of bioglycerol with urea. The BET specific surface area and oxygen vacancies of SnO2 were significantly enhanced after the addition of MoO3 and WO3 promoters. TEM images revealed the formation of nanosized particles with a diameter of around 5–25?nm for the synthesized catalysts. The MoO3/SnO2 catalyst exhibited a high conversion and selectivity towards glycerol carbonate in comparison to other catalysts. The observed better performance is attributed to unique properties of MoO3/SnO2 catalyst including smaller crystallite size, high specific surface area, abundant oxygen vacancies, and more number of acidic sites. This catalyst also exhibited remarkable stability with no significant loss of activity in the recycling experiments. Graphic Abstract: Nanostructured MoO3/SnO2 solid acid catalyst exhibited an excellent catalytic activity and a high selectivity to glycerol carbonate in the carbonylation of bioglycerol with urea under solvent-free and mild conditions.[Figure not available: see fulltext.]
- Mallesham, Baithy,Rangaswamy, Agolu,Rao, Bolla Govinda,Rao, Tumula Venkateshwar,Reddy, Benjaram M.
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p. 3626 - 3641
(2020/05/19)
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- Versatile and scalable synthesis of cyclic organic carbonates under organocatalytic continuous flow conditions
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The benchmark route for the preparation of cyclic organic carbonates starts from toxic, volatile and unstable epoxides. In this work, cyclic organic carbonates are prepared according to alternative sustainable and intensified continuous flow conditions from the corresponding 1,2-diols. The process utilizes dimethyl carbonate (DMC) as a low toxicity carbonation reagent and relies on the organocatalytic activity of widely available and cheap organic ammonium and phosphonium salts. Glycerol is selected as a model substrate for preliminary optimization with a library of homogeneous ammonium and phosphonium salts. The nature of the anion dramatically influences the catalytic activity, while the nature of the cation does not impact the reaction. Upon optimization, glycerol carbonate is obtained in 95% conversion and 79% selectivity within 3 min residence time at 180 °C (11 bar) with 3.5 mol% of tetrabutylammonium bromide as the organocatalyst. A straightforward liquid-liquid extraction procedure enables both the purification of glycerol carbonate and the recycling of the homogeneous catalyst. The conditions are amenable to refined and crude bio-based glycerol, although conversions are lower in the latter case. Control experiments suggest that water present in the crude samples induces significant hydrolysis of glycerol carbonate. The reaction conditions are then successfully applied on a wide variety of substrates, affording the corresponding cyclic carbonates in overall good to excellent yields (20 examples, 45-95%). The substrate scope notably encompasses bio-based starting materials such as glycerol ethers and erythritol-derived diols. In-line NMR is featured as a qualitative analytical tool for real-time reaction monitoring. The scalability of this carbonation procedure on glycerol is assessed in a commercial pilot-scale silicon carbide continuous flow reactor of 60 mL internal volume. Glycerol carbonate is obtained in 76% yield, corresponding to a productivity of 13.6 kg per day.
- Gérardy, Romaric,Estager, Julien,Luis, Patricia,Debecker, Damien P.,Monbaliu, Jean-Christophe M.
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p. 6841 - 6851
(2019/12/24)
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- Functionalized quaternary ammonium salt ionic liquids (FQAILs) as an economic and efficient catalyst for synthesis of glycerol carbonate from glycerol and dimethyl carbonate
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A series of functionalized quaternary ammonium salt ionic liquids (FQAILs) with different functional groups, such as hydroxyl, carboxyl, ether group, and amino, were prepared and used as a catalyst for the synthesis of glycerol carbonate from transesterification of glycerol and dimethyl carbonate without any additional organic solvent and co-catalyst. The effects of functional groups, anions (Cl?, Br?, I?, OH?), and reaction parameters were investigated in detail. It is found that both the cation and anion of FQAILs display an important effect on its catalytic activity. Among these FQAILs, hydroxyl functionalized ionic liquid, [HPTPA]OH possesses the highest activity because there are the strong interactions between hydroxyl and dimethyl carbonate molecular and between anion OH? and glycerol molecular, which were shown by FTIR spectra. The glycerol conversion of 96.2% and glycerol carbonate yield of 87.6% can be obtained over [HPTPA]OH under moderate conditions of reaction temperature of 80 °C, reaction time of 90 min, dimethyl carbonate/glycerol molar ratio of 3, and catalyst amount of 0.9 mol% based on glycerol amount. The [HPTPA]OH catalyst can be reused at least three cycles without significant reduction in its catalytic activity. Finally, a possible reaction mechanism for the synthesis of glycerol carbonate is also proposed.
- Elhaj, Elrasheed,Wang, Huajun,Gu, Yanlong
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- Method for Enzymatic Method for Glycerol Carbonate Preparation from Carbon dioxide
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The present invention relates to a method for manufacturing glycerol carbonate using enzymes from glycerol and carbon dioxide, wherein the method, by manufacturing glycerol carbonate from carbon dioxide and glycerol in an effort to reduce a generation amount, has an effect of manufacturing glycerol carbonate which can not only reduce carbon dioxide and glycerol, but also has high value.(AA) Carbonic anhydrase(BB) Catalyst(C1,C2) LipaseCOPYRIGHT KIPO 2020
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Paragraph 0118-0120
(2020/03/24)
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- Novel and effective strategy of dual bis(trifluoromethylsulfonyl)imide imidazolium ionic liquid immobilized on periodic mesoporous organosilica for greener cycloaddition of carbon dioxide to epoxides
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Novel periodic mesoporous organosilica supported nanocatalysts with different loading levels of a bis(trifluoromethylsulfonyl)imide anion-based dual imidazolium ionic liquid have been prepared and evaluated as efficient catalysts for the cycloaddition of CO2 to epoxides. The as-fabricated PMO@IL-NTf2(1.0) exhibited the best catalytic performance with excellent conversions (98-100%) and yields (96-99%) at 90 °C and 0.6 MPa for 0.5-1 h, based on a synergistic effect between the dual nucleophilic anion sites of the imidazolium ionic liquid and the hydroxyl group sites of periodic mesoporous organosilica. The excellent recyclability and operational simplicity make this protocol economic and environment-friendly.
- Jin, Tan,Dong, Fang,Liu, Yang,Hu, Yu Lin
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p. 2583 - 2590
(2019/02/12)
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- Efficient CO2 fixation into cyclic carbonates catalyzed by NNO-scorpionate zinc complexes
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A series of new chiral zwitterionic NNO-scorpionate mononuclear zinc alkyls [Zn(R)(κ3-NNO)]Br was developed in very high yields via suitable quaternization in the scorpionate ligand. These zwitterionic complexes performed as bifunctional cataly
- Sobrino, Sonia,Navarro, Marta,Fernández-Baeza, Juan,Sánchez-Barba, Luis F.,Garcés, Andrés,Lara-Sánchez, Agustín,Castro-Osma, José A.
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p. 10733 - 10742
(2019/07/22)
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- ONO pincer type ligand complexes of Al(III) as efficient catalyst for chemical fixation of CO2 to epoxides at atmospheric pressure
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Carbon dioxide, the main cause of environmental pollution, its utilization to produce valuable products is of utmost interest. A series ONO pincer hydrazone based most active mono-nuclear Al(III) complexes were successfully synthesized and characterized with the help of NMR, IR, mass spectrometry and only complex 2a was confirmed by single-crystal analysis. The synthesized Al(III) complexes were then employed as capable catalysts for the solvent-free chemical fixation of CO2 with epoxides at atmospheric pressure and could be reused five times without loss of any catalytic activity. In addition, the catalytic mechanism was investigated by analyzing intermediates via 1H NMR, 13C NMR, and mass MALDI-TOF. The excellent catalytic performance could be due to simultaneous attack and the opening of the epoxide by metal centers to form an alkoxide ion which activates the CO2 the same time.
- Ullah, Habib,Mousavi, Bibimaryam,Younus, Hussein A.,Khattak, Zafar A.K.,Suleman, Suleman,Jan, Muhammad T.,Yu, Baoyi,Chaemchuen, Somboon,Verpoort, Francis
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p. 190 - 198
(2019/08/07)
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- Influence of the Counterion on the Synthesis of Cyclic Carbonates Catalyzed by Bifunctional Aluminum Complexes
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New bifunctional aluminum complexes have been prepared with the aim of studying the effect of a counterion on the synthesis of cyclic carbonates from epoxides and carbon dioxide (CO2). Neutral ligand 1 was used as a precursor to obtain four nov
- Martínez, Javier,De La Cruz-Martínez, Felipe,Gaona, Miguel A.,Pinilla-Pealver, Esther,Fernández-Baeza, Juan,Rodríguez, Ana M.,Castro-Osma, José A.,Otero, Antonio,Lara-Sánchez, Agustín
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supporting information
p. 3396 - 3408
(2019/02/19)
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- Aromatic guanidines as highly active binary catalytic systems for the fixation of CO2 into cyclic carbonates under mild conditions
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We have synthesised a set of aromatic mono- and bis(guanidines) which are highly effective binary catalytic systems (guanidine/cocatalyst) for the formation of cyclic carbonates. The presence of multiple N-H bonds causes a modification in the traditional
- Mesías-Salazar, ángela,Martínez, Javier,Rojas, René S.,Carrillo-Hermosilla, Fernando,Ramos, Alberto,Fernández-Galán, Rafael,Anti?olo, Antonio
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p. 3879 - 3886
(2019/08/12)
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- Efficient Catalysts In situ Generated from Zinc, Amide and Benzyl Bromide for Epoxide/CO2 Coupling Reaction at Atmospheric Pressure
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Herein, in situ generated efficient catalysts were designed for fixation of CO2 to cyclic carbonates under mild conditions. Zinc bromide and N,N-dibenzyl-N,N-dimethylammonium bromide, being proved as active catalyst species, were in situ generated from cheap Zn powder, dimethyl formamide and benzyl bromide, and catalyzed the cycloaddition reaction of CO2 and various terminal epoxides in moderate to excellent yields at 80 °C and atmospheric pressure of CO2. The protocol circumvents the preparation of active catalysts, simultaneously possesses good catalytic activity under mild conditions.
- Zhang, Shuai,Han, Feng,Yan, Shaorui,He, Mingyue,Miao, Chengxia,He, Liang-Nian
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p. 1311 - 1316
(2019/01/09)
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- Synergistic cooperation of bi-active hydrogen atoms in protic carboxyl imidazolium ionic liquids to push cycloaddition of CO2 under benign conditions
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Nine protic carboxyl imidazolium ionic liquids are synthesized. Then, they are employed to catalyze the chemical fixation of carbon dioxide (CO2) and propylene oxide leading to propylene carbonate in the absence of co-catalyst and organic solvent. HCPImBr presents the best catalytic activity with the product yield of 92% under reaction temperature 120 °C, CO2 initial pressure 1.5 MPa, catalyst amount 0.5 mol%, and reaction time 2.0 h. Even if the reaction temperature and CO2 initial pressure are decreased to 80 °C and 1.0 MPa, respectively, the 85% of product yield would be kept with the 1.0% catalyst dosage along with 12.0 h. With the exception of the most optimal reaction conditions, generality, and recyclability of HCPImBr are also investigated. More importantly, the reaction mechanism is investigated by the density functional theory, which is the first time to report the mechanism for protic carboxyl imidazolium ionic liquids. The catalytic activity of ionic liquids would be further improved with the reasonable combination of cation and anion.
- Wang, Tengfei,Zhu, Xinrui,Mao, Lemin,Liu, Yi,Ren, Tiegang,Wang, Li,Zhang, Jinglai
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- Bifunctional coordination polymers as efficient catalysts for carbon dioxide conversion
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The multidentate ligand H2L upon complexation with Zn (II) and Cd (II) provide a one-dimensional polymeric networks. These coordination polymers (CPs) CP-1 and CP-2 containing Zn (II) and Cd (II) metals respectively are well characterized. The
- Arunachalam, Rajendran,Chinnaraja, Eswaran,Valkonen, Arto,Rissanen, Kari,Subramanian, Palani S.
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- Synthesis of helical aluminium catalysts for cyclic carbonate formation
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Helical aluminium complexes [Al2X4(μ-nbptam)] (X = Me 1, Et 2), [Al2X4(μ-fbpam)] (R = Me 3, Et 4), [Al3X7(μ-nbptam)] (X = Me 5, Et 6) and [Al3X7(μ-fbpam)] (X = Me 7, E
- Gaona, Miguel A.,De La Cruz-Martínez, Felipe,Fernández-Baeza, Juan,Sánchez-Barba, Luis F.,Alonso-Moreno, Carlos,Rodríguez, Ana M.,Rodríguez-Diéguez, Antonio,Castro-Osma, José A.,Otero, Antonio,Lara-Sánchez, Agustín
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supporting information
p. 4218 - 4227
(2019/04/01)
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- Hydroxyl-functionalized pyrazolium ionic liquids to catalyze chemical fixation of CO2: Further benign reaction condition for the single-component catalyst
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Lots of ionic liquids have been utilized as catalyst for the coupling reaction of carbon dioxide with epoxides, however, catalyzed conditions could not be regarded as benign, especially when no co-catalyst and/or organic solvent is involved. A series of hydroxyl-functionalized pyrazolium ionic liquids are firstly synthesized. They would efficiently catalyze the cycloaddition of carbon dioxide and propylene oxide under 110 °C and 1.0 MPa carbon dioxide initial pressure with 1 mol% catalyst during 4 h resulting in the product yield of 91.2%. The catalytic condition is greatly refined as compared with other single-component ionic liquids with simple anion. Simultaneously, the effect of reaction temperature, amount of catalyst, carbon dioxide initial pressure, and reaction time is explored along with the reusability of catalyst. For most of epoxides with terminal substituted group, HEEPzBr presents acceptable catalytic activity. The difference of HEMPzBr, HEEPzBr, and HPEPzBr is also explored by the density functional theory calculations.
- Wang, Tengfei,Ma, Yuan,Jiang, Jiamin,Zhu, Xinrui,Fan, Baowan,Yu, Guanyao,Li, Ningning,Wang, Shasha,Ren, Tiegang,Wang, Li,Zhang, Jinglai
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- Synthesis of Homo- And Heteronuclear Rare-Earth Metal Complexes Stabilized by Ethanolamine-Bridged Bis(phenolato) Ligands and Their Application in Catalyzing Reactions of CO2 and Epoxides
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A series of homonuclear rare-earth (RE) metal complexes (1Y, 2Yb, 3Nd, and 4La) and heteronuclear RE-Zn complexes (1Y-Zn, 3Nd-Zn, and 5Sm-Zn) stabilized by ethanolamine-bridged bis(phenolato) ligands was prepared and structurally characterized. Heteronuclear complexes are assembled through bridging acetate ligands, and their formation and characterization add to the diversity of 3d-4f complexes. Their activities in mediating reactions of CO2 and epoxides were evaluated and compared. Heteronuclear RE-Zn complexes found application in the copolymerization of cyclohexene oxide and CO2, giving rise to acetate-group-capped copolymers. Homonuclear complexes showed good activity in catalyzing the cycloaddition of variously monosubstituted epoxides and CO2 (1 bar), generating cyclic carbonates in 65-96% yield. For sterically hindered disubstituted epoxides, good yields of 60-91% were achieved in the presence of 10 bar CO2
- Hua, Linyan,Li, Baoxia,Han, Cuiting,Gao, Pengfei,Wang, Yaorong,Yuan, Dan,Yao, Yingming
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p. 8775 - 8786
(2019/07/03)
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