- Synthesis of alcohol ester 12 in 1, 8-diazabicyclo [5.4.0] undec-7-ene (DBU)-based Self-separation catalytic system
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The synthesis of alcohol ester 12 is one of the valuable industrial processes, but it was impeded by poor separating property and recycling ability of the catalytic systems. Herein, four novel DBU-based basic ionic liquids (DBILs) of [BDBU]IM, [BDBU]OH, [ODBU]IM, [[ODBU]OH were synthesized successfully by introducing the alkyl chains of 1-bromobutane or 1-bromooctane to 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU), and then, employing imidazole (IM?) or hydroxide (OH?) as counter ions. The above obtained four ionic liquids were applied in the synthesis of alcohol ester 12 in isobutyraldehyde (IBD)/aqueous media for the first time. Interestingly, after reaction, production of alcohol ester 12 can be self-separated from ionic liquids/water (ILs/W) catalytic system automatically. Furthermore, the self-separated ILs/W can be recycled and used in next catalytic reaction for at least 5 times without obvious loss of catalytic performance. In this work, the structure, purity, thermal stability and alkalinity of DBILs were characterized systematically. [BDBU]IM shows high alkalinity and thus enhances yield of 66.17%. From thermo gravimetric analyzer (TGA), [BDBU]IM also exhibits excellent thermal stability. So [BDBU]IM was chosen for the further studying. Furthermore, quantum chemistry is applied to calculate the interaction forces and electron energies of reactants by DFT, and the calculation results illustrate the feasibility of synthetic process of DBILs. The self-separation strategy of DBILS in this work may open up a new avenue for the clean synthesis of other industrial products.
- Lv, Zhiguo,Zhang, Shuying,Guo, Zhenmei,Cheng, Xi,Wang, Jiaomei,Zhang, Chao
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- Synthesis method for 1,3-glycol monoester
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The invention relates to a synthesis method for a 1,3-glycol monoester. The synthesis method comprises the following steps: by taking nano aluminum oxide as a catalyst, basic carbonate and an alkalineearth metal oxide as additives, performing a condensation reaction on an alkyl aldehyde compound for 3-6 hours; and performing separation purification on the obtained mixture, so as to obtain the 1,3-glycol monoester, wherein the nano aluminum oxide is gamma-Al2O3. Due to adoption of the specific catalyst, the condensation reaction of the alkyl aldehyde compound is not retained at a double-molecule aldehyde condensation stage, and the 1,3-glycol monoester can be prepared through continuous condensation.
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Paragraph 0025-0035
(2019/11/12)
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- Method for synthesis of 2, 2, 4-trimethyl-1, 3-pentanediol monoisobutyrate
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The invention discloses a method for one-step direct synthesis of 2, 2, 4-trimethyl-1, 3-pentanediol monoisobutyrate from isobutyraldehyde in the presence of a strong basic ionic liquid as a catalyst.The method comprises that isobutyraldehyde undergoes aldol condensation and Cannizzaro reaction through one step in the presence of a strong basic ionic liquid as a catalyst to produce 2, 2, 4-trimethyl-1, 3-pentanediol monoisobutyrate. The method solves the problems of toxicity and corrosion of an inorganic base catalyst and complicated processes of the two-stage reaction and realizes high product selectivity, few by-products, simple processes, energy saving, emission reduction and catalyst recycling.
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Paragraph 0012-0018
(2018/03/26)
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- Method for preparing 2, 2, 4-trimethyl-1, 3-pentanediol double isobutyric acid ester
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The invention discloses a method for preparing 2, 2, 4-trimethyl-1, 3-pentanediol double isobutyric acid ester. The method includes the steps that 1, an alkali metal hydroxide, a phase transfer catalyst and water are mixed in a certain proportion, and isobutyraldehyde is dropwise added slowly; the temperature is raised to 30-50 DEG C after the isobutyraldehyde is dropwise added completely, and heat preservation is conducted for 1-5 hours; 2, the temperature is lowered to room temperature, a water phase is removed, the alkali metal hydroxide is added to an organic phase in a certain proportion, the temperature is raised to 60-70 DEG C, and a heat preservation reaction is conducted for 6-12 hours; 3, the temperature is lowered to the room temperature, the alkali metal hydroxide is removed, and the remaining organic phase is reserved; 4, a certain quantity of isobutyric acid, a solid sulfate catalyst and a water-carrying agent are added to the remaining organic phase, the mixture is heated to 120-150 DEG C, and a heat preservation reaction is conducted for 2-5 hours; after the reaction is completed, filtering is conducted to remove the solid sulfate catalyst, water washing is conducted to remove isobutyric acid which does not participate in the reaction, the water-carrying agent is removed through rotary evaporation, reduced pressure distillation is conducted, and a target product is obtained. Compared with the prior art, by means of the preparation method, the target product is high in yield, the operation process is simple and safe, and industrialized production is achieved easily.
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Paragraph 0028; 0029; 0030
(2016/11/28)
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- Method for directly synthesizing 2,2,4-trimethyl-1,3-pentanediol diisobutyrate from isobutyraldehyde
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The invention belongs to the field of fine chemical engineering, and particularly relates to a method for directly synthesizing 2,2,4-trimethyl-1,3-pentanediol diisobutyrate from isobutyraldehyde. According to the method, isobutyraldehyde, as a by-product of an industrial butanol-octanol production process, is taken as a raw material, and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate is directly synthesized. The method comprises the following steps: firstly, conducting aldol condensation and disproportionation-esterification on part of isobutyraldehyde to obtain 2,2,4-trimethyl-1,3-pentanediol isobutyrate; then, conducting oxidization on the remaining unreacted isobutyraldehyde to generate isobutyric acid, wherein separation and purification are not needed; finally, carrying out an esterification reaction to obtain 2,2,4-trimethyl-1,3-pentanediol diisobutyrate. The method has the following advantages: the raw material is cheap and easy to obtain, and can be recycled for several times; the intermediate product needs not be separated and can be directly synthesized into the final product, so as to simplify the technical operation process for generation of the final product; and the raw material conversion rate is high, that is, the isobutyraldehyde conversion rate exceeds 92%.
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Paragraph 0054; 0056; 0057
(2016/10/24)
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- Trimerization of aldehydes with one α-hydrogen catalyzed by sodium hydroxide
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Trimerization of 2-methylpropanal (isobutyraldehyde) is a simple and effective method to synthesize 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate and 2,2,4-trimethyl-1,3-pentanediol-3-monoisobutyrate which are often used as film forming auxiliaries in paints. The use of solid sodium hydroxide as a catalyst provides an excellent yield of above 85 % after the optimization of the reaction time and the catalyst dosage. Furthermore, trimerization of four other aldehydes with one α-hydrogen catalyzed by solid sodium hydroxide can also take place and the yield of 1,3-diol monoesters reaches 50-70 %. Trimerization of aldehydes with one α-hydrogen can be explained by a three-step reaction mechanism: (i) aldol condensation of aldehyde; (ii) crossed Cannizzaro reaction; and (iii) esterification of carboxylic acid and alcohol.
- Li, Yu-Gang,Luo, Chen-Xi,Qian, Chao,Chen, Xin-Zhi
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p. 422 - 426
(2014/01/06)
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- A method to manufacture a mixture of aliphatic hydroxyesters, especially from isobutyric aldehyde
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A method to manufacture a mixture of aliphatic hydroxyesters, especially from isobutyric aldehyde, is characterized by that the isobutyric aldehyde condensation reaction is carried out in the presence of a mixture of sodium hydroxide and sodium isobutyrate as catalyst in a weight ratio of 3:1, first at 58-60% conversions of isobutyric aldehyde to 2,2,4-trimethyl-1,3-pentanediol isobutyrate at temperatures in the range 58-62°C during 8-12 minutes and then at 68-72% conversions of isobutyric aldehyde to 2,2,4-trimethyl-1,3-pentanediol isobutyrate at temperatures in the range 88-92°C during 3-7 minutes whereupon, from a mixture of 3-hydroxy-2,2,4-trimethylpentyl isobutyrate and 3-hydroxy-2,2-dimethyl-1-(1-methylethyl)propyl isobutyrate, an aqueous solution of the catalyst is separated by allowing to stand and elution from the organic phase of the mixture after the condensation reaction while the process of distillation of the remaining portion of the mixture after the condensation reaction is carried out in four steps.
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Page/Page column 3-5
(2012/04/17)
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- Fast aldol-Tishchenko reaction utilizing 1,3-diol monoalcoholates as the catalysts
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The aldol-Tishchenko reaction of enolizable aldehydes is a simple and effective way to prepare 1,3-diol monoesters, which are widely used as coalescing agents in the paint industry. The use of monoalcoholates of 1,3-diols as catalysts gives fast and clean reactions compared with the previous use of several inorganic catalysts. The use of the proper 1,3-diol moiety in the catalyst also reduces the amount of side products which are due to ester interchange between product esters and the catalyst. The rapid water-free method developed herein allows fast preparation of monoesters with excellent yield and minimized formation of side products.
- Toermaekangas, Olli P.,Koskinen, Ari M. P.
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p. 421 - 425
(2013/09/07)
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- SELECTIVE TRIMERIZATION OF ALIPHATIC ALDEHYDES CATALYZED BY POLYNUCLEAR CARBONYLFERRATES
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Aliphatic aldehydes undergo a catalytic trimerization to give 1,3-diol monoesters upon treatment with Fe3(CO)12 in pyridine or with Fe3(CO)12-pyridine N-oxide in benzene.Polynuclear carbonylferrates serve as catalyst for this transformation.
- Ito, Keiji,Kamiyama, Nobuhiro,Nakanishi, Saburo,Otsuji, Yoshio
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p. 657 - 660
(2007/10/02)
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- Lithium Tungsten Dioxide Promoted Claisen-Tishchenko Condensation of Aromatic and Aliphatic Aldehydes
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Lithium tungsten dioxide, LiWO2, has been shown to be a useful catalyst for effecting the Claisen-Tishchenko condensation of aldehydes under heterogeneous conditions.
- Villacorta, Gilberto M.,Filippo, Joseph San
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p. 1151 - 1154
(2007/10/02)
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