- Control of morphology and catalytic activity of a cationic layered material
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We have discovered three new synthetic pathways to our two-dimensional cationic inorganic material, antimony oxide hydroxide ethanedisulfonate, [Sb4O4(OH)2](O3SCH 2CH2SO3)?H2O. These new methods include room temperature conditions and allow control of crystal size and morphology for improved catalytic performance of the material. As a benchmark reaction, we studied ketalization of 2-butanone with 1,2-ethanediol, a common step for carbonyl group protection. Our material is easily recovered for reuse and gives a higher yield and turnover rates than the typical iodine or toluenesulfonate homogeneous catalyst. The yield ranged between 79 and 92%, with the crystals from reflux conditions giving the highest yield when used as-synthesized. The morphology and properties for each crystal growth method are described in detail. A repeated catalysis study with powdered samples increases the yield to ca. 97%.
- Swanson, Claudia H.,Shaikh, Harris A.,Abdollahian, Yashar,Hauser, Jesse L.,Ikehata, Mariko,Oliver, Scott R.J.
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- Three-dimensional phosphine metal-organic frameworks assembled from Cu(I) and pyridyl diphosphine
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Metal-organic frameworks (MOFs) with phosphine based ligands are extremely attractive for catalysis. In this paper, phosphine has been successfully incorporated for the first time into three-dimensional (3D) MOFs. The MOFs are based on rigid L2M2 dimeric secondary building blocks assembled from Cu(I) and a pyridyl diphosphine ligand, 4-(3,5- bis(diphenylphosphino)phenyl)pyridine, with Br- (CuL-Br), Cl - (CuL-Br), or PF6- (CuL-PF6) as counteranions. The structures have a 4.122 net topology, which can be further simplified to 64.82-qtz. The MOFs contain 1D homochiral channels. The PF6- anions hosted in the 1D channel of CuL-PF6 can be readily exchanged with Br- or Cl- while keeping the framework intact. The materials show anion-tunable flexible porosity. CuL-Br reveals gradual uptake of MeOH, while CuL-PF6 exhibits stepwise sorption for MeOH. The heterogeneous Lewis acid catalytic activity of the MOFs has been shown in ketalization reaction. CuL-Br and CuL-PF6 are active in the reactions between ethylene glycol and 2-butanone/cyclohexanone, up to 93% yield with 0.2 mol % catalyst loading. In contrast, no reaction happens between ethylene glycol and bulky benzophenone, suggesting profound size selectivity. The catalysts can be reused with the framework left intact for three runs without loss of activity.
- Tan, Xin,Li, Lei,Zhang, Jianyong,Han, Xiaorui,Jiang, Long,Li, Fuwei,Su, Cheng-Yong
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- Synthesis of 1-bromo-3-buten-2-one
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A synthetic method for 1-bromo-3-buten-2-one is given. The compound is prepared through the following sequence: 2-butanone to 2-methyl-2-ethyl-1,3- dioxolane to 2-(1-bromoethyl)-2-bromomethyl-1,3-dioxolane to 2-bromomethyl-2- vinyl-1,3-dioxolane to the final product. Full experimental details including spectral data are given.
- Westerlund, Andreas,Carlson, Rolf
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- Cationic two-dimensional inorganic networks of antimony oxide hydroxide for Lewis acid catalysis
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We have successfully synthesized a rare example of inorganic layered materials possessing a positive charge, which is well outside the isostructural set of layered double hydroxides. This layered architecture consists of two-dimensional corrugated [Sb2O2(OH)]+ layers with linear α,ω-alkanedisulfonate anions residing in the interlamellar space. This cationic material displays a chemical robustness under highly acidic aqueous conditions (pH = 1). Combining the robust nature and the high density of SbIII sites on the exposed crystal facets, our cationic layered material is an efficient, recyclable catalyst for cyanosilylation of benzaldehyde derivatives with trimethylsilyl cyanide. In addition, the Lewis acidity of the SbIII sites also catalyzes the ketalization of carbonyl groups under "green" solvent-free conditions.
- Yin, Jinlin,Fei, Honghan
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- Solvothermal synthesis, structure and catalytic activity of a mixed-valence CuI/CuII complex with 1-D chain structure
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A complex of composition [CuI4CuII(mtpo) 4(H2O)2Cl2]n (1) was synthesized from reaction of Hmtpo (Hmtpo = 5-methyl-[l,2,4]-triazolo-[l,5-a]- pyrimidin-7-o1) with one equivalent of CuCl2·2H2O in water at 100 °C under autogenous pressure. Complex 1 was fully characterized by X-ray single crystal diffraction, elemental analysis and IR spectroscopy. X-ray analysis reveals that complex 1 is a mixed-valence coordination polymer and displays 1-D chain structure. Compound 1 was able to heterogeneously catalyze the ketalization reaction of 2-butanone and ethylene glycol to afford 2-ethyl-2-methyl-[1,3]-dioxolane in excellent yield under mild conditions.
- Han, Zhi-Ping,Li, Yahong
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- Synthesis of a novel melamine-formaldehyde resin-supported ionic liquid with Bronsted acid sites and its catalytic activities
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Bronsted acidic ionic liquid immobilized on a melamine-formaldehyde resin (AIL-MFR) was synthesized through the reaction of melamine-formaldehyde resin (MFR) with 1,4-butanesulfonate. Using PEG-2000 as the additive, the MFR can be prepared in regular microspheres with an average diameter of 3.97 μm and surface area of 9.09 m2 g-1. The AIL-MFR had high acidity of 2.93 mmol g-1, mainly from the sulfonic groups. The catalysis results showed that the AIL-MFR had high activity and stability for acetalization with excellent conversions and yields for most substrates. Furthermore, immobilization of the acidic ionic liquid on the MFR made the recycling of the catalyst convenient.
- Xing, Guiying
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- First Example of a Nonanuclear Silver Sulfate Hybrid Cluster: Green Approach for Synthesis of Lewis Acid Catalyst
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Finding a high nuclearity hybrid framework with novel structure and properties by an environmentally benign approach is a really challenging task. Herein, a green strategy for synthesis of a new inorganic-organic hybrid framework solid has been described. The framework contains silver sulfate clusters with nine different silver ions with shortest silver-silver connectivity. The present compound is the first example of nonanuclear silver sulfate hybrid framework with a new topology. The hybrid solid compound shows a highly active Lewis acidic nature for the various heterogeneous catalytic reactions such as cyanosilylation, ketalization, and esterification with quantitative transformation and recyclability.
- Paul, Avijit Kumar,Naveen, Kumari,Kumar, Nikhil,Kanagaraj, Rajendiran,Vidya,Rom, Tanmay
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- Hydrothermal synthesis of two cationic bismuthate clusters: An alkylenedisulfonate bridged hexamer, [Bi6O4(OH) 4(H2O)2][(CH2)2(SO 3)2]3 and a rare nonamer templated by triflate, [Bi9O8(OH)6][CF3SO 3]5
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This paper reports the synthesis, characterization, and application of two cationic bismuthate clusters by anion templating. The compounds were synthesized under mild hydrothermal treatment and characterized by powder and single-crystal X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis. The first material consists of a cationic hexanuclear bismuthate cluster octahedral in geometry and linked by 1,2-ethanedisulfonate molecules. This structure is thermally stable to about 235 °C. In the second compound, discrete cationic nonanuclear bismuthate clusters interact electrostatically with trifluoromethanesulfonate anions to pack into a nearly layered assembly. The material undergoes a transformation to Bi2O3 upon loss of the triflate groups at about 385 °C. Both materials demonstrate the use of sulfonate groups for the anion-directed assembly of these rare cationic inorganic structures. The application of the 3D octahedral bismuth cluster material toward acidic heterogeneous catalysis is also reported.
- Rogow, David L.,Fei, Honghan,Brennan, Daniel P.,Ikehata, Mariko,Zavalij, Peter Y.,Oliver, Allen G.,Oliver, Scott R. J.
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- Facile preparation of ionic liquid functionalized magnetic nano-solid acid catalysts for acetalization reaction
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The facile two-step preparation procedure of a novel magnetic nano-solid acid catalyst is described, which includes grafting an ionic liquid onto Fe 3O4 nanoparticles, followed by the sulfonation of phenyl groups in the ionic liquid. The catalytic performance of this novel material has been systematically studied in the acetal formation of benzaldehyde and ethylene glycol. The experimental results testify this catalyst possesses high catalytic activity with a yield of 97% under mild reaction conditions. Furthermore, the catalyst is readily separated using a permanent magnet and it is reusable without any significant decrease in catalytic activity.
- Wang, Ping,Kong, Aiguo,Wang, Wenjuan,Zhu, Haiyan,Shan, Yongkui
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- Polyacrylonitrile fiber mat supported solid acid catalyst for acetalization
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A novel polyacrylonitrile hybrid fiber mat supported solid acid catalyst was prepared by electrospin-ning, and its catalytic activities were carefully investigated through acetalization reactions. The results showed that this hybrid fiber mat exhibits high activity for the reactions, with average yields over 95%. Besides having catalytic activities similar to the solid acid, the heterogeneous solid acid/polyacrylonitrile mat can be reused in six runs without significant loss of catalytic activities. The large size of the hybrid fiber mat greatly facilitates recovery of the catalyst from the reaction mixture. The high and stable catalytic activities of the hybrid fiber mat hold great potential for green chemical processes and preparation of membrane reactors in the future.
- Shao, Linjun,Du, Yijun,Xing, Guiying,Lv, Weixi,Liang, Xuezheng,Qi, Chenze
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- One-pot synthesis of ordered mesoporous zirconium oxophosphate with high thermostability and acidic properties
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A series of mesoporous zirconium oxophosphate (M-ZrPO) with different P/Zr molar ratios (0-1.25) has been prepared via a facile one-pot evaporation-induced self-assembly (EISA) strategy. After removing the structure-directing agents, the M-ZrPO with large specific surface area (160 m2 g-1), big pore volume (0.26 cm3 g-1) and narrow pore size distribution (5.64 nm) has been obtained. Small-angle X-ray diffraction (SXRD) and transmission electron microscopy (TEM) results showed that these materials had ordered mesoporous structure. With the increase of P/Zr, the textural properties of M-ZrPO could be improved. Moreover, the ordered mesostructure could be maintained even when treated at 800°C, indicating the M-ZrPO had attractive thermal stability. NH3-TPD and pyridine-IR analyses showed the presence of abundant Broensted and Lewis acid sites in the material. The M-ZrPO has been used successfully as solid acid catalyst and showed excellent performance in the ketalization reaction.
- Miao, Zhichao,Xu, Leilei,Song, Huanling,Zhao, Huahua,Chou, Lingjun
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- Phosphorus promoted SO42-/TiO2 solid acid catalyst for acetalization reaction
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A novel phosphorus modifed SO42-/TiO2 catalyst was synthesized by a facile coprecipitation method, followed by calcination. The catalytic performance of this novel solid acid was evaluated by acetalization. The results showed that the phosphorus was very effcient to enhance the catalytic activity of SO42-/TiO2. The solid acid owned high activity for the acetalization with the yields over 90%. Moreover, the solid acid could be reused for six times without loss of initial catalytic activities.
- Zhong, Shaofeng,Ou, Qiongrong,Shao, Linjun
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- Interpenetrated and Catenated Zinc Thiosulfates Frameworks with dia and qtz Nets: Synthesis, Structure, and Properties
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Reactions between Zn(NO3)2·6H2O, Na2S2O3, 4,4′-bipyridine (bpy), 1,2-bis(4-pyridyl)ethene (bpe), 1,2-bis(4-pyridyl)ethane (bpa), and 1,3-bis(4-pyridyl)propane (bpp) under solvothermal conditions resulted in four new zinc thiosulfate hybrid compounds. Compound I has four-membered zinc thiosulfate rings connected by the ligand, 1,3-bis(4-pyridyl)propane (bpp) forming a two-dimensional structure. Compounds II-IV have one-dimensional zinc thiosulfate chains connected by the ligands, bpy (II), bpe (III), and bpa (IV) giving rise to three-dimensional structures. All the four-structures exhibit 3-fold interpenetration. Proton conductivity studies indicate reasonable proton mobility at 34 °C and at 98% relative humidity. The compounds also exhibit Lewis acid character and good photocatalytic activity for the decomposition of cationic dyes.
- Karthik, Rajendran,Natarajan, Srinivasan
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- Preparation of a novel solid acid catalyst with Lewis and Bronsted acid sites and its application in acetalization
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A novel melamine-formaldehyde resin (MFR) supported solid acid with Lewis and Bronsted acid sites was synthesized through the immobilization of acidic ionic liquid and cuprous ion on MFR. The scanning electron microscopy (SEM) characterization showed that addition of PEG-2000 in the synthesis of MFR could promote the formation of regular particles with diameters around 3.7 μm. The XRD pattern demonstrated that some cuprous ions were aggregated. The catalytic performance of this acid catalyst was evaluated by acetalization. The results showed that the catalytic activity of MFR with Bronsted acid could be improved by addition of Lewis acid. The solid acid was very efficient for the acetalization of carbonyl compounds and diols with moderate to excellent yields and there was no loss of catalytic activity even after being recycled for 6 runs. TUeBITAK.
- Du, Yijun,Shao, Linjun,Luo, Lingyan,Shi, Si,Qi, Chenze
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- Reversible anion exchange and catalytic properties of two cationic metal-organic frameworks based on Cu(I) and Ag(I)
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We report the synthesis and characterization of two Ag(I)/Cu(I)-based cationic metal-organic frameworks and their application in both heterogeneous catalysis and anion exchange. The Cu(I)-based material was designed from our previously reported Ag(I) cationic topology. Both structures consist of cationic layers with π-π stacked chains of alternating metal and 4,4′-bipyridine. α,Ω-Alkanedisulfonate serves as an anionic template, electrostatically bonding to the cationic layers. Due to weak interaction between the sulfonate template and cationic extended framework, both materials display reversible anion exchange for a variety of inorganic species. Indeed, the Ag(I)-based material exhibits highly efficient uptake of permanganate and perrhenate anion trapping, a model for pertechnetate trapping. The materials also display heterogeneous Lewis acidity, likely due to the coordinatively unsaturated metal sites which only bind to two bipy nitrogens and a weak interaction with one sulfonate oxygen. A comparative study on the influence of structure versus size selectivity and reusability for both exchange and catalysis is discussed.
- Fei, Honghan,Rogow, David L.,Oliver, Scott R. J.
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- An efficient procedure for protection of carbonyls in Br?nsted acidic ionic liquid [Hmim]BF4
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Protection of carbonyls as acetals or ketals using Br?nsted acidic ionic liquid [Hmim]BF4 as catalyst as well as solvent was investigated. Satisfactory results were obtained for the protection of carbonyls as cycloacetals or ketals with diols. The product can be separated conveniently from the reaction system, and the ionic liquid can be reused after removal of water.
- Wu, Hai-Hong,Yang, Fan,Cui, Peng,Tang, Jie,He, Ming-Yuan
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- Solvent-free ketalization of polyols over germanosilicate zeolites: The role of the nature and strength of acid sites
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Isomorphic substitution of silicon for germanium affords germanosilicate zeolites with weak acid centers capable of catalyzing key reactions such as Baeyer-Villiger oxidation of ketones and etherification of levulinic acid. Herein, we show for the first time that UTL (Si/Ge = 4.2) and IWW (Si/Ge = 7.2) germanosilicate zeolites are active and selective catalysts of polyol (e.g., ethylene glycol, glycerol and 1,4 butanediol) ketalization to dioxolanes. Large-pore IWW outperformed the extra-large-pore UTL zeolite in the ketalization of polyols, thus indicating diffusion limitations in bulky platelet-like UTL crystals. FTIR spectroscopy of adsorbed pyridine revealed the Lewis acidity of the UTL zeolite, whereas the more active IWW catalyst was characterized by water-induced Br?nsted acidity. Increasing the activation temperature (200-450 °C) reduced the concentration of Br?nsted acid centers in the IWW germanosilicate (i.e., 0.16; 0.07 and 0.05 mmol g-1 for Tact = 200, 300 and 450 °C, respectively) but increased the number of Lewis acid sites in both zeolites. Under optimized reaction conditions (e.g., acetone/glycerol = 25, Tact = 300 °C), almost total transformation of glycerol into solketal was achieved within 3 h of reaction time over the IWW zeolite at room temperature (>99% yield of the target product). The results from the present study clearly show that weak acid centers of germanosilicate zeolites can serve as active sites in ketalization reactions.
- Podolean, Iunia,Zhang, Jin,Shamzhy, Mariya,Parvulescu, Vasile I.,?ejka, Ji?í
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p. 8254 - 8264
(2020/12/30)
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- Robust acidic pseudo-ionic liquid catalyst with self-separation ability for esterification and acetalization
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The novel acidic pseudo-ionic liquid catalyst with self-separation ability has been synthesized through the quaternization of triphenylphosphine and the acidification with silicotungstic acid. The pseudo-IL showed high activities for the esterification with average conversions over 90%. The pseudo-IL showed even higher activities for acetalization than traditional sulfuric acid. The homogeneous catalytic process benefited the mass transfer efficiency. The pseudo-IL separated from the reaction mixture automatically after reactions, which was superior to other IL catalysts. The high catalytic activities, easy reusability and high stability were the key properties of the novel catalyst, which hold great potential for green chemical processes.
- Shi, Yingxia,Liang, Xuezheng
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p. 1413 - 1421
(2019/05/04)
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- Synthesis of dioxolanes and oxazolidines by silica gel catalysis
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Abstract: Ethylene glycol condensed with carbonyl compounds in the presence of silica gel or alumina, without solvent and under pressure, affords 1,3-dioxolanes. 2-Amino-2-methylpropanol also condensed with carbonyl compounds in the presence of silica gel or an acid-activated clay, without solvent and under pressure, produces oxazolidines. To explain these results, we propose that the glycol and the aminopropanol react with Br?nsted (H+) and Lewis acid sites (Si and Al) located on the surface of the catalysts, leading to the products via various ionic intermediates.
- Rohand, Taoufik,Savary, Jér?me,Markó, István E.
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p. 1429 - 1436
(2018/06/25)
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- First Example of a Nonanuclear Silver Sulfate Hybrid Cluster: Green Approach for Synthesis of Lewis Acid Catalyst
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Finding a high nuclearity hybrid framework with novel structure and properties by an environmentally benign approach is a really challenging task. Herein, a green strategy for synthesis of a new inorganic-organic hybrid framework solid has been described. The framework contains silver sulfate clusters with nine different silver ions with shortest silver-silver connectivity. The present compound is the first example of nonanuclear silver sulfate hybrid framework with a new topology. The hybrid solid compound shows a highly active Lewis acidic nature for the various heterogeneous catalytic reactions such as cyanosilylation, ketalization, and esterification with quantitative transformation and recyclability.
- Paul, Avijit Kumar,Naveen, Kumari,Kumar, Nikhil,Kanagaraj, Rajendiran,Vidya,Rom, Tanmay
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- Syntheses, structures, and catalytic activities of copper(I) complexes with the ligand 2(4,5-diphenyl-1H-imidazol-2-yl)pyridine
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Two copper(I) complexes of compositions [Cu(HL)I]2·EtOH (1) and [Cu(HL)3]I·MeOH (2) were synthesized via the reactions of HL [HL = 2(4,5-diphenyl-1H-imidazol-2-yl)pyridine] and CuI in EtOH and MeOH, respectively, under solvothermal conditions. The complexes were characterized by X-ray single crystal diffraction, IR spectroscopy, and elemental analysis. Compounds 1 and 2 are catalytically active towards ketalization reaction, giving various ketals under mild conditions. Copyright
- Yang, Hua,Liu, Yonglu,Hu, Dao-Dao
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p. 394 - 397
(2014/03/21)
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- Bis(perfluorooctanesulfonyl)imide supported on fluorous silica gel: Application to protection of carbonyls
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The immobilization of bis(perfluorooctanesulfonyl)imide (HNPf2) on fluorous silica gel (FSG) and its utilization in protection of carbonyls have been investigated. This system is reasonably general and can be applied to converting several carbonyls to the corresponding acetals and ketals in good to excellent yields. There is no need for the use of anhydrous solvents or inert atmosphere. Recycling studies have shown that the FSG-supported HNPf2 catalyst can be readily recovered and reused several times without significant loss of activity.
- Hong, Mei,Xiao, Guomin
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experimental part
p. 121 - 126
(2012/08/28)
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- PROCESS FOR THE PRODUCTION OF ETHYLENE GLYCOL
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The present invention provides a process for the production of monoethylene glycol, said process comprising the steps of: (a) reacting ethylene oxide with a ketone in the presence of a solid acidic catalyst to form a ketal; and (b) hydrolysing the ketal with water to form monoethylene glycol, wherein the ketone contains in the range of from 4 to 20 carbon atoms.
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Page/Page column 10-12; 5/7
(2011/02/24)
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- [Hmim]3PW12O40: A high-efficient and green catalyst for the acetalization of carbonyl compounds
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[Hmim]3PW12O40 was developed and used in the acetalization of carbonyl compounds in excellent yields. The ionic liquid-heteropoly acid hybrid compound and reaction medium formed temperature-dependent phase-separation system with the ease of product as well as catalyst separation. The catalyst was recycled more than 10 times without any apparent loss of catalytic activity.
- Dai, Yan,Li, Bin Dong,Quan, Heng Dao,Lü, Chun Xu
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experimental part
p. 678 - 681
(2011/10/31)
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- Synthesis, characterization, and catalytic application of a cationic metal-organic framework: Ag2(4,4′-bipy)2(O 3SCH2CH2so3)
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We report a silver-based cationic metal-organic framework with two mixed organic linkers directing the structure. The structure consists of ID Ag(4,4′-bipy) cationic chains arranged into closepacked layers. Weakly bound alkanedisulfonate anions charge-balance the layers, where only one oxygen of each sulfonate makes a long contact with the Ag. The unsaturated linear Ag centers likely allow the Lewis acidity displayed by the material for ketone protection as well as esterification. The material showed no reduction in yield after three catalytic runs with average 95% conversion yield for ketal formation and 57% for esterification without further water removal. In addition to hydrothermal conditions, the structure can be synthesized by reflux or room temperature, with almost identical catalytic ability. Other properties of this compound including chemical and thermal stability are also described.
- Fei, Honghan,Paw U, Latisha,Rogow, David L.,Bresler, Marc R.,Abdollahian, Yashar A.,Oliver, Scott R. J.
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experimental part
p. 2027 - 2032
(2011/12/02)
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- Application of Functional Ionic Liquids Possessing Two Adjacent Acid Sites for Acetalization of Aldehydes
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Several acid functional ionic liquids, in which cations possess two adjacent acid sites, were synthesized and used for the acetalization of aldehydes with good catalytic performance under mild reaction conditions.
- Li, Dongmei,Shi, Feng,Peng, Jiajian,Guo, Shu,Deng, Youquan
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p. 3582 - 3585
(2007/10/03)
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- Synthesis of 1,3-dioxolanes catalysed by AlPO4 and AlPO4-Al2O3: kinetic and mechanistic studies
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A number of aldehydes and ketones were easily and quantitatively converted to the corresponding 1,3-dioxolanes by the reaction with ethylene glycol over four synthetic amorphous AlPO4 and AlPO4-Al2O3 catalysts using acetonitrile as the solvent at different temperatures in the range 30-60 deg C without the formation of any by-product.The influence of the number of acid sites on the catalyst surface as well as the substituent effects of different carbonyl compounds studied can be evaluated through several isokinetic parameters obtained owing to the existence of a linearfree-energy relationship (LFER).The results obtained account for an intermediate in the transition state whose relative stability is determined by the resonance between the carbonyl group and their substituents, but its evolution is via a concerted process in two adsorption-desorption steps.
- Bautista, Felipa M.,Campelo, Juan M.,Garcia, Angel,Leon, Josefa,Luna, Diego,Marinas, Jose M.
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p. 815 - 822
(2007/10/02)
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- Aromatic urea derivatives and their use as herbicide
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This invention relates to novel compounds of formula [I], a process for their production, and their use as a herbicide. STR1 wherein A represents the bond STR2 in which X is a hydrogen atom, a chlorine atom, a nitro group or a trifluoromethyl group; B represents a hydrogen atom, a methyl group or a methoxy group; and Ar represents one member selected from the group consisting of STR3 in which R1 to R38, are as defined hereinafter.
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- Investigation of the Effectiveness of Various 1-Dialkylamino-1-methoxycarbenium-Methyl Sulfates in the Course of Acetalization
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The rate of dimethyl ketal formation from acetone and methanol in the presence of several 1-dialkylamino-1-methoxycarbenium methyl sulfates 1a, 5a-g is studied.The fastest rate was observed in the case of 5c.In the presence of 5c, the reaction of carbonyl compounds with either methanol or 1,2-diols gave the dimethyl ketals 6 and 1,3-dioxolanes 7, respectively.
- Kantlehner, Willi,Gutbrod, Heinz-Dieter,Funke, Bernd
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p. 246 - 252
(2007/10/02)
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