1680-31-5Relevant articles and documents
Influence of the functionalization degree of acidic ion-exchange resins on ethyl octyl ether formation
Guilera, Jordi,Hanková, Libuse,Jerabek, Karel,Ramírez, Eliana,Tejero, Javier
, p. 14 - 22 (2014)
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.
Bisimidazolium Tungstate Ionic Liquids: Highly Efficient Catalysts for the Synthesis of Linear Organic Carbonates by the Reaction of Ethylene Carbonate with Alcohols
Huang, Jie,Tao, Huilin,Wang, Yingting,Wu, Shi,Yu, Zhongliang,Zhang, Yongfan
, (2022/03/08)
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.]
Room temperature and normal pressure preparation method of organic carbonate
-
Paragraph 0109-0111, (2020/07/15)
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.
Method for preparing dialkyl carbonate by alcoholysis of urea
-
Paragraph 0050, (2018/09/08)
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.