- Influence of the functionalization degree of acidic ion-exchange resins on ethyl octyl ether formation
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Ethyl octyl ether (EOE) can be obtained by the ethylation of 1-octanol by means of ethanol or diethyl carbonate over acidic ion-exchange resins. However, EOE formation has to compete with the less steric demanding formation of diethyl ether, by-product obtained from ethanol dehydration or diethyl carbonate decomposition. In the present work, the influence of the resin functionalization degree on EOE formation has been evaluated. A series of partially sulfonated resins (0.87-4.31 mmol H+/g) were prepared by the sulfonation of a macroreticular styrene-divinylbenzene copolymer. The catalysts were characterized, and subsequently, tested in a batch reactor (T = 150 C, P = 25 bar). Amberlyst 15 and 46 were also tested for comparison purposes. Catalytic runs revealed that EOE formation occurred mainly in the firstly sulfonated domain of the polymer skeleton, the least crosslinked; while diethyl ether was formed in the whole polymer bead. Accordingly, the functionalization of the least accessible polymer domain, as a result of increasing the sulfonation temperature or by using a pre-swelling solvent, is not suitable to produce long chain ethers such as EOE; which are preferred as diesel fuels.
- Guilera, Jordi,Hanková, Libuse,Jerabek, Karel,Ramírez, Eliana,Tejero, Javier
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Read Online
- Bisimidazolium Tungstate Ionic Liquids: Highly Efficient Catalysts for the Synthesis of Linear Organic Carbonates by the Reaction of Ethylene Carbonate with Alcohols
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A series of bisimidazolium tungstate ionic liquids were synthesized and applied to catalyze the reaction of ethylene carbonate (EC) with alcohols. A detailed investigation was carried out on the relationship between catalyst structures and catalytic activities. The result showed that 1-butyl-3-methyl-bisimidazolium tungstate ([Bmim]2WO4) containing double C2–H in bisimidazolium and WO42? had more effectively catalytic performance than other bisimidazolium tungstate and conventional imidazolium salt (OAc?, Cl?, Br?). Under the optimized conditions of 1:15 molar ratio of EC and ethanol, 5?mol% [Bmim]2WO4, 85?°C and 0.5?h, the yield of diethyl carbonate (DEC) was nearly 100%. The detailed DFT calculations and NMR spectroscopy indicated that the high catalytic activity of [Bmim]2WO4 was not only because the strong nucleophilic ability of WO42? could activate ethanol, but also the special structure of double C2–H in bisimidazolium could cooperatively activate EC. The reaction was catalyzed by synergistic effect in double C2–H and WO42? of [Bmim]2WO4. In addition, [Bmim]2WO4 could be used seven times without significant loss of catalytic activity. Graphical Abstract: [Figure not available: see fulltext.]
- Huang, Jie,Tao, Huilin,Wang, Yingting,Wu, Shi,Yu, Zhongliang,Zhang, Yongfan
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- Room temperature and normal pressure preparation method of organic carbonate
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The invention relates to the technical field of organic synthesis, and provides a room temperature and normal pressure preparation method of organic carbonate. The method comprises the following steps: introducing carbon dioxide into an imidazole ionic liquid to obtain a mixture; mixing the obtained mixture with alcohol and halogenated hydrocarbon, and carrying out addition-substitution reactionsto obtain organic carbonate. The whole reaction process is carried out at a room temperature under a normal pressure. The activation energy of the reaction is reduced by using imidazole ionic liquid and halogenated hydrocarbon, and finally, organic carbonate is prepared from CO2 at a room temperature under a normal pressure.
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Paragraph 0109-0111
(2020/07/15)
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- Method for synthesizing organic carbonate from carbon dioxide, alcohol and brominated alkane under mild conditions
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The invention discloses a method for synthesizing organic carbonate from carbon dioxide, alcohol and brominated alkane under mild conditions, belonging to the field of chemical synthesis. According tothe method, carbon dioxide, alcohol and brominated alkane are used as raw materials, 1,8-diazabicycloundec-7-ene (DBU) is used as an activating agent, and acetonitrile is used as a solvent to preparethe organic carbonate. The target product, namely the organic carbonate with excellent yield can be obtained under optimized reaction conditions. The method is mild in reaction conditions, simple andconvenient to operate and high in yield, and is an excellent system for preparing the organic carbonate.
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Paragraph 0016-0017; 0018-0020; 0023-0024
(2020/06/02)
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- Method of manufacturing Dialkyl carbonate using carbon dioxide
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In the embodiment of the present invention consists of a carbon dioxide using the d alkyl car this [thu [thu] which it sees a manufacturing method is provided other [...] number one, alcohol, imidazolium cation and bicarbonate mixing negative catalyst and bases the solvent to form a mixture, said mixture by mixing said reactants including injecting carbon dioxide for generating an agitating the manufacturing method characterized in that the d alkyl car this [thu [thu] which it sees a number [...] substrate. (by machine translation)
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Paragraph 0073-0079; 0088; 0149-0151
(2019/08/12)
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- Method for preparing dialkyl carbonate by alcoholysis of urea
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The invention relates to a method for preparing dialkyl carbonate by alcoholysis of urea, belonging to the field of chemical synthesis. More specifically, the invention relates to preparation of dialkyl carbonate. The method comprises the following step: subjecting urea and alkyl monohydric alcohol to a reflux reaction under stirring for 6 to 30 hours under the condition of normal pressure or reduced pressure at a reaction temperature of 70 to 150 DEG C by using one or more selected from the group consisting of metal magnesium, calcium, aluminum, chromium, manganese, iron, cobalt, nickel, copper or zinc as a main catalyst and one or more compounds containing donor atom nitrogen, phosphorus, oxygen or sulfur as an auxiliary catalyst so as to prepare the dialkyl carbonate. The preparation method provided by the invention has the following advantages: the dialkyl carbonate is prepared with high selectivity and high yield at a low reaction temperature under the condition of normal pressureor reduced pressure; simple operation, high safety and low cost are achieved in the processing process; and good industrial application prospects are obtained.
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Paragraph 0050
(2018/09/08)
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- Organic carbonate synthesis from CO2 and alcohol over CeO 2 with 2-cyanopyridine: Scope and mechanistic studies
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The combination system of CeO2-catalyzed carboxylation and 2-cyanopyridine hydration (CeO2 + 2-cyanopyridine system) is effective for the direct synthesis of organic carbonates from CO2 and alcohols. This catalyst system can be applied to various alcohols to afford the corresponding carbonates in high alcohol-based yields. The hydration of 2-cyanopyridine over CeO2 rapidly proceeds under the low concentration of water, which can remove the water from the reaction media. Since the reaction is limited by the chemical equilibrium, the removal of water remarkably shifts the chemical equilibrium to the carbonate side, leading to high carbonate yields. In addition, 2-picolinamide that is produced by hydration of 2-cyanopyridine forms an intramolecular hydrogen bonding between H atom of the amide group and N atom of the pyridine ring, which weakens the adsorption of 2-picolinamide on CeO2 by reduction of the acidity. The reaction mechanism of DMC formation in CeO2 + 2-cyanopyridine system is also proposed.
- Honda, Masayoshi,Tamura, Masazumi,Nakagawa, Yoshinao,Nakao, Kenji,Suzuki, Kimihito,Tomishige, Keiichi
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- Mild and efficient capture and functionalisation of CO2 using silver(i) oxide and application to 13C-labelled dialkyl carbonates
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A high yielding three-component reaction between β-iodo ethylamine derivatives, MeOH and gaseous CO2 at ambient temperatures and pressures is reported using silver(i) oxide. Unfunctionalised alkyl iodides were also found to be effective in this transformation and their optimisation is also described. To highlight the ease and control with which gaseous CO 2 can be captured and functionalised under mild conditions, the reaction was performed using 13C-enriched CO2 to afford specifically 13C-carbonyl-labelled dialkyl carbonates with exquisite control of the isotopic purity in good yields and without the need for specialised equipment.
- Tunbridge, Gemma A.,Baruchello, Riccardo,Caggiano, Lorenzo
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p. 4613 - 4621
(2013/05/08)
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- Graphite oxide activated zeolite NaY: Applications in alcohol dehydration
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A mixture of graphite oxide (GO) and the zeolite NaY (Si/Al = 5.1) was used to dehydrate various alcohols to their respective olefinic products. Using conditions optimized for 4-heptanol (15 wt% GO-NaY (1 : 1 wt/wt), 150°C, 30 min), a series of secondary and tertiary aliphatic alcohols were cleanly dehydrated in moderate to excellent conversions (27.5-97.2%). Several primary alcohols were also dehydrated, although higher catalyst loadings (200 wt% GO-NaY (1 : 1) and longer reaction times (3 h) were required. The enhanced dehydration activity was attributed to the ability of GO to convert NaY to an acidic form and without the need for ammonium cation exchange and/or high temperature calcination. The Royal Society of Chemistry 2013.
- Todd, Alexander D.,Bielawski, Christopher W.
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p. 135 - 139
(2013/03/29)
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- Synthesis of carbonates directly from 1 atm CO2 and alcohols using CH2Cl2
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We introduced here a new one-pot, general procedure for the preparation of dialkyl carbonates from alcohols in a straightforward fashion under 1 atm pressure of CO2 using Cs2CO3 and CH 2Cl2 as key reagents.
- Yamazaki, Yusuke,Kakuma, Kasumi,Du, Ya,Saito, Susumu
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experimental part
p. 9675 - 9680
(2011/02/24)
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- The continuous acid-catalysed etherification of aliphatic alcohols using stoichiometric quantities of dialkyl carbonates
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A range of methyl and ethyl ethers of aliphatic alcohols have been synthesized cleanly in high yield by reacting the corresponding alcohol with dimethyl carbonate or diethyl carbonate over the solid acid catalyst, I-alumina. The reaction could be conducted at ambient pressure without the need for the large excess of dialkyl carbonate as previously reported in the literature. If the reaction was conducted at high pressure, the conversion of the starting alcohol was greatly reduced. However, high pressure CO2 can be used as the solvent without significant reduction in yield. This has implications for tandem reactions.
- Parrott, Andrew J.,Bourne, Richard A.,Gooden, Peter N.,Poliakoff, Martyn,Irvine, Derek J.,Bevinakatti, Han. S.
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supporting information; experimental part
p. 1420 - 1426
(2011/09/20)
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- Synthesis of carbamates from amines and dialkyl carbonates: Influence of leaving and entering groups
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A number of carbamates were synthesised through a halogen-free process by reacting amines with symmetrical and unsymmetrical carbonates. The results obtained showed a specific trend of preferred leaving groups (in the dialkyl carbonates) depending on whether a catalyst or a base was used. On the other hand, investigations conducted on the preferred entering groups (amines) for the synthesis of carbamates showed the same trend regardless of whether a catalyst or a base was used. Finally, in accordance with the results obtained, it was possible to synthesise sterically hindered carbamates in high yield by transesterification of methyl carbamate with a sterically hindered alcohol. Georg Thieme Verlag Stuttgart New York.
- Tundo, Pietro,McElroy, C. Robert,Aricò, Fabio
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supporting information; experimental part
p. 1567 - 1571
(2010/09/05)
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- Synthesis and Characterization of Dialkyl Carbonates Prepared from Mid-, Long-Chain, and Guerbet Alcohols
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A series of organic carbonates derived from mid-, long-chain, and Guerbet alcohols were synthesized in good yields (69-80% isolated yields after purification by distillation or recrystallization) through a carbonate interchange reaction by heating the linear or Guerbet alcohols with diethyl carbonate in the presence of catalyst, n-dibutyltin oxide. The carbonates were isolated by Kuegelrohr distillation or recrystallization from acetone and characterized using FTIR, GC, 11H and 13C NMR spectroscopy, and GC-MS. El and positive Cl mass-spectral techniques were used to characterize the carbonates. Such materials are currently of commercial interest as lubricants and additives in various industrial applications.
- Kenar, James A.,Knothe, Gerhard,Copes, Ashley L.
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p. 285 - 291
(2007/10/03)
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- Carbonylbiscaprolactam: A Versatile Reagent for Organic Synthesis and Isocyanate-Free Urethane Chemistry
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The power of the rings: The reactions of carbonylbiscaprolactam (CBC, 1) with amines and alcohols proceed either by ring elimination (RE) or by ring opening (RO). The conversion and selectivity of these reactions were optimized in studies with various hydroxy and amino compounds, catalysts, reaction temperatures, and ratios of 1/nucleophile.
- Maier, Steffen,Loontjens, Ton,Scholtens, Boudewijn,Muelhaupt, Rolf
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p. 5094 - 5097
(2007/10/03)
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- A useful conversion of alcohols to alkyl fluorides
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A useful conversion of alcohols to alkyl fluorides via their fluoroformates is introduced. The fluoroformates are obtained in nearly quantitative yield from the alcohols by treatment with COF2 (generated in situ from bis(trichloromethyl) carbonate) in ether with KF as an added acid scavenger. The neat fluoroformates are cleaved to the fluorides by heating at 120-125°C using hexabutylguanidinium fluoride (HBGF) as the catalyst.
- Flosser, David A,Olofson, Roy A
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p. 4275 - 4279
(2007/10/03)
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- Clear antiperspirants and deodorants made with siloxane-based polyamides
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Clear antiperspirant and/or deodorant compositions, especially clear sticks having good structural integrity, can be formed by incorporating at least 8% by weight based on the total weight of the composition of a selected siliconized polyamide into a product formulated with at least one silicone material and at least one non-silicone emollient. The siliconized polyamides have the silicone portion in the acid side of the polyamide and are selected so that: (a) the degree of polymerization in the silicone portion is in the range of 12-18; (b) the average molecular weight of the siliconized polyamide is at least 50,000 daltons with at least 95% of the polyamide having a molecular weight greater than 10,000 as measured by size exclusion chromatography; and (c) the polydispersity is less than 20.
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- Polyol esters of ether carboxylic acids and fiber finishing methods
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A compound of the general formula (I) STR1 wherein R is alkyl from about 4 to about 22 carbon atoms, R1 and R2 independently of one another are alkyl from about 1 to about 22 carbon atoms, X is either sulphur or oxygen, Y is --C2 H4 O-- or --C3 H6 O-- or a mixture of --C2 H4 O and --C3 H6 O--, m is a number from about 1 to about 20, n is a number from about 1 to about 6, p is a number from 2 to 4, q is a number from 0 to about 2 and r is a number from 0 to about 2, with q+r+p being the integer 4. This invention is also directed m the method for treating fibers by applying this compound.
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- Vinyl carbonates as novel alkoxycarbonylation reagents in enzymatic synthesis of carbonates
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Carbonates could be obtained by enzymatic alkoxycarbonylation from vinyl carbonates, which are easily prepared from vinyl chloroformate. The reaction was catalyzed by Candida antarctica lipases, SP 435 and SP 435 A. The method could be also used for the synthesis of carbamates. When racemic alcohols were used, lipase catalyzed their resolution, and chiral carbonates were obtained with different enantiomeric excesses depending upon the structure of the alcohol.
- Pozo,Pulido,Gotor
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p. 6477 - 6484
(2007/10/02)
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- Applications of Phase Transfer Catalysis. 15. Phase Transfer Catalytic Preparation of Carbonic Esters Without the Use of Phosgene
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Carbonic esters can be prepared in a phase-transfer catalytic reaction from primary alkyl halides and a mixture of dry potassium hydrogen carbonate and dry potassium carbonate in non-polar solvents.The conversion is ineffective in the absence of hydrogen carbonate and catalyst.
- Lissel, Manfred,Dehmlow, Eckehard V.
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p. 1210 - 1215
(2007/10/02)
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