123-79-5Relevant academic research and scientific papers
Novel fluorination of polystyrene sulfonic acid resin by CF3SO3H for high stability and strong acidity
Lang, Xuewei,Jia, Wenzhi,Wang, Yanan,Zhu, Zhirong
, p. 58 - 61 (2015)
A novel fluorination method derived from CF3SO3H was employed to the polystyrene sulfonic acid resin, to enhance its acid strength and stability. The as-prepared CF3SO2-resin was characterized by FT-IR, XPS, 31P MAS NMR, and chemical titration, and its catalytic performance was tested. It was found that CF3SO2-resin exhibited higher selectivity to benzyltoluene in the Friedel-Crafts alkylation of toluene with benzyl alcohol, excellent catalytic activity with 96% conversion and a good recyclability over seven times in esterification of 1, 6-hexanedioic acid with 2-ethylhexanol.
Biomass-derived dibasic acids to diesters with inorganic ligand-supported catalyst: synthesis, optimization, characterization
Chen, Zhe,Han, Sheng,Lu, Deli,Xu, Yumeng
, (2021/08/23)
Several attempts have been made to obtain aliphatic dicarboxylic diesters from esterification reaction to develop the biomass-derived platform molecules and green manufacturing processes. In this paper, Na3(H2O)6[AlMo6O18(OH)6], an Anderson-type polyoxometalate, firstly, was reported as a catalyst for diester synthesis from dicarboxylic acid to diester which showed an well productivity and selectivity characterized by 1H and 13C. Response surface methodology (RSM) integrated with the desirability function approach was used to determine the best operative conditions, and the optimal reaction parameters for maximum dipropyl succinate yield (77 ± 2.5%) were identified as 1.19?mol.% catalyst loading, 4.9:1 propanol/succinic acid ratio, 113?°C, and 9.6?h. Three batches of tests were carried for catalyst recycling with 78–75% yield even after 6 cycles of esterification. In addition, the substrate carbon chain was increased for investigation of substrate scope achieving satisfactory results and all products were characterized by 1H and 13C nuclear magnetic resonance spectroscopy.
Efficient Palladium-Catalyzed Carbonylation of 1,3-Dienes: Selective Synthesis of Adipates and Other Aliphatic Diesters
Yang, Ji,Liu, Jiawang,Ge, Yao,Huang, Weiheng,Ferretti, Francesco,Neumann, Helfried,Jiao, Haijun,Franke, Robert,Jackstell, Ralf,Beller, Matthias
supporting information, p. 9527 - 9533 (2021/03/08)
The dicarbonylation of 1,3-butadiene to adipic acid derivatives offers the potential for a more cost-efficient and environmentally benign industrial process. However, the complex reaction network of regioisomeric carbonylation and isomerization pathways, make a selective and direct transformation particularly difficult. Here, we report surprising solvent effects on this palladium-catalysed process in the presence of 1,2-bis-di-tert-butylphosphin-oxylene (dtbpx) ligands, which allow adipate diester formation from 1,3-butadiene, carbon monoxide, and methanol with 97 % selectivity and 100 % atom-economy under scalable conditions. Under optimal conditions a variety of di- and triesters from 1,2- and 1,3-dienes can be obtained in good to excellent yields.
Preparation method for catalytic synthesis of adipic acid dialkyl ester by heteropolyacid
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Paragraph 0034-0035, (2021/01/15)
The invention relates to a preparation method for catalytic synthesis of adipic acid dialkyl ester by heteropolyacid. The method specifically comprises the following steps: 1) mixing adipic acid, alcohol and heteropolyacid, uniformly stirring, and carrying out esterification reaction; and 2) after the esterification reaction is finished, standing and filtering to remove heteropoly acid, adding a sodium carbonate aqueous solution to obtain an organic phase and a water phase, taking the organic phase, concentrating and drying to obtain the product adipic acid dialkyl ester. Compared with the prior art, the raw materials are easy to obtain, the preparation method is simple, the preparation method is economical and environmentally friendly, and the adopted catalyst has the advantages of beinghigh in reaction activity, easy to recycle and the like.
Direct synthesis of adipic acid esters via palladium-catalyzed carbonylation of 1,3-dienes
Yang, Ji,Liu, Jiawang,Neumann, Helfried,Franke, Robert,Jackstell, Ralf,Beller, Matthias
, p. 1514 - 1517 (2020/01/08)
The direct carbonylation of 1,3-butadiene offers the potential for a more cost-efficient and environmentally benign route to industrially important adipic acid derivatives. However, owing to the complex reaction network of regioisomeric carbonylation and isomerization pathways, a selective practical catalyst for this process has thus far proven elusive. Here, we report the design of a pyridyl-substituted bidentate phosphine ligand (HeMaRaphos) that, upon coordination to palladium, catalyzes adipate diester formation from 1,3-butadiene, carbon monoxide, and butanol with 97% selectivity and 100% atom-economy under industrially viable and scalable conditions (turnover number > 60,000). This catalyst system also affords access to a variety of other di- and triesters from 1,2- and 1,3-dienes.
Mono-substitution of symmetric diesters: Selectivity of: Mycobacterium smegmatis acyltransferase variants
Finnveden, Maja,Semlitsch, Stefan,He, Oscar,Martinelle, Mats
, p. 4920 - 4927 (2019/10/05)
A method for selectively reacting one, out of two identical carboxylic esters in a symmetric diester has been developed. An esterase from Mycobacterium smegmatis (MsAcT) has a restricted active site resulting in a narrow acyl donor specificity. This constraint was used to develop a selective synthesis route from divinyl adipate (a symmetric diester) towards mixed vinyl adipate esters. To find a suitable catalyst, the wild type (wt) MsAcT and two MsAcT variants: A single point mutant (L12A) and a double point mutant (T93A/F154A), were immobilized and studied under solvent-free conditions. Out of the tested catalysts, MsAcT L12A was the most selective for mono-Transesterification of divinyl adipate. When divinyl adipate was reacted with 1.5 equivalents of a hydroxyl vinyl ether full conversion of DVA was observed yielding over 95% mixed diester. Furthermore, the limitations for longer dicarboxylic esters were studied, showing that MsAcT T93A/F154A tolerated up to at least dimethyl sebacate.
Efficient direct ester condensation between equimolar amounts of carboxylic acids and alcohols catalyzed by trifluoromethanesulfonic acid (TfOH) in Solkane365mfc
Xu, Xiu-Hua,Azuma, Ayaka,Taniguchi, Misaki,Tokunaga, Etsuko,Shibata, Norio
, p. 3848 - 3852 (2013/04/23)
A simple, practical, and environmentally benign esterification protocol has been devised on the basis of TfOH as the catalyst and Solkane365mfc as the reaction medium. The direct condensation of equimolar amounts of various carboxylic acids and alcohols was conveniently carried out without recourse to any additional water removal technique, giving the desired carboxylic esters in excellent yields.
SKIN EXTERNAL PREPARATIONS AND COSMETICS
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, (2010/12/29)
An object of the present invention is to provide skin external preparations and cosmetics which contain a branched acyl carnitine and have excellent formulation stability. A skin external preparation of the present invention includes a carnitine derivative represented by the following Formula (1) and/or a carnitine derivative salt represented by the following Formula (2), and an amphoteric surfactant. In Formula (1), R1 and R2 are each independently a C1-18 optionally branched, saturated or unsaturated aliphatic hydrocarbon group. In Formula (2), R1 and R2 are the same as in Formula (1), X? is a specific anion and Y+ is a specific cation.
Some unusual reactivities in the SmI2-mediated reductive coupling of acrylamides and acrylates with imides
Taaning, Rolf H.,Lindsay, Karl B.,Skrydstrup, Troels
experimental part, p. 10908 - 10916 (2010/02/27)
A serendipitous discovery of some intra-molecular enolate addition reactions following a SmI2-mediated reductive cross-coupling between imides and electron-deficient olefins leading to some novel compounds was investigated to determine the generality of the protocol and the possible mechanistic pathways involved. This provided a Z-selective synthesis of γ-ketoenediamides in good yields, albeit as of now the substrate scope remains limited. It was also shown that the seemingly similar acrylate substrates can behave differently compared to the corresponding acrylamides in their SmI2-mediated reductive cross-coupling reaction with imides, and it was argued that these diverging reactivities are dominated by the ability of the acrylates to coordinate the samarium metal centre.
NOVEL FORMULATION OF DEHYDRATED LIPID VESICLES FOR CONTROLLED RELEASE OF ACTIVE PHARMACEUTICAL INGREDIENT VIA INHALATION
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, (2009/03/07)
A new formulation of dehydrated lipid vesicles employs a vesicle preserver and permits the control of release and delivery of active pharmaceutical ingredients into the respiratory system for treatment in particular of asthma. The typical formulation provides controlled release of the active pharmaceutical ingredient from 0% to 100% from 0 to 72 hours after inhalation, changes the systemic administration to topical administration, allows prolonged therapeutic period for one administration, increased stability, with reduced dose, reduced systemic side effects, reduced toxicity.
