- Highly selective one-step dehydration, decarboxylation and hydrogenation of citric acid to methylsuccinic acid
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The one-step dehydration, decarboxylation and hydrogenation of the bio-based and widely available citric acid is presented. This reaction sequence yields methylsuccinic acid with yields of up to 89%. Optimal balances between the reaction rates of the different steps were found by varying the hydrogenation catalyst and the reaction parameters (H2 pressure, pH, temperature, time and catalyst-to-substrate ratio).
- Verduyckt, Jasper,De Vos, Dirk E.
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Read Online
- Efficient conversion of bio-renewable citric acid to high-value carboxylic acids on stable solid catalysts
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Citric acid is an important biomass-derived platform chemical for the synthesis of high-value organic acids, such as itaconic acid (ICA), 2-methylsuccinic acid (MSA) and tricarballylic acid (TCA). However, these reactions frequently encounter low efficiency and severe leaching of catalysts imposed by the acidity of citric acid under hydrothermal conditions, limiting their practical applications. Here, we report that highly acid- and etching-resistant monoclinic zirconium dioxide (m-ZrO2) exhibited high catalytic efficiency in the conversion of citric acid to ICA via sequential dehydration and decarboxylation steps, providing a high yield of 70.3% at 180 °C on m-ZrO2 (calcined at 300 °C). The correlation between the activity of the m-ZrO2 catalysts and their acid-basicity demonstrates that the synergistic effect of acidic and basic sites facilitates the rate-determining dehydration step for the citric acid conversion to ICA. On the bifunctional catalysts, Pt and Pd nanoparticles supported on P25 and anatase TiO2, citric acid can be selectively converted to MSA and TCA, respectively, with yields as high as 83.1% and 64.9%. The hydrogenation activity of the bifunctional catalysts was found to be crucial for regulating the relative rates of the decarboxylation and hydrogenation steps involved in the selective conversion of citric acid to MSA and TCA. These catalysts showed excellent stability and recyclability in acidic aqueous solutions. This study provides a rationale for tuning catalytic functions required for the green production of important carboxylic acids from citric acid and other biomass-derived feedstocks. This journal is
- Li, Zhaowei,Liu, Haichao,Wen, Xin
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p. 1650 - 1658
(2022/03/07)
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- The crystal structure of mouse IRG1 suggests that cis-aconitate decarboxylase has an open and closed conformation
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Itaconate, produced as an offshoot of the TCA cycle, is a multifunctional immunometabolite possessing antibacterial, antiviral, immune regulation, and tumor progression activities. The production of itaconate in biological systems is catalyzed by cis-aconitate decarboxylase (CAD, also known as immune responsive gene 1 (IRG1) in mammals). In this study, we solved the structure of IRG1 from Mus musculus (mouse IRG1). Structural comparison analysis revealed that IRG1 can exist in either an open or closed conformation and that this is controlled by the A1 loop located proximal to the active site. Our closed form structure was maintained by an unidentified molecule in the active site, which might mimic its substrate. Protein Data Bank accession codes Coordinate and structural factors were deposited with the Protein Data Bank under PDB ID: 7BR9.
- Chun, Hye Lin,Lee, So Yeon,Kim, Ki-Hwa,Lee, Chang Sup,Oh, Tae-Jin,Ho Park, Hyun
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- METHOD FOR THE PRODUCTION OF METHYLSUCCINIC ACID AND THE ANHYDRIDE THEREOF FROM CITRIC ACID
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A process for the preparation of methylsuccinic acid in any form, including its salts, its mono- and diester derivatives and the anhydride thereof, which comprises reacting citric acid or a derivative thereof in decarboxylation conditions, said process comprising (i) reacting citric acid or mono- and diester derivatives thereof in a non- aqueous solvent, specifically excluding alcohols, on a metallic catalyst at a temperature between 50 to 400°C and under a partial hydrogen pressure from 0.1 to 50 bar or (ii) reacting citric acid or any salt thereof or mono-, di- and triester derivatives thereof on a metallic catalyst in solvents comprising at least 5% water, at a temperature of from 50 to 400°C under a hydrogen partial pressure from 0.1 to 400 bar
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Page/Page column 15
(2018/04/21)
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- BIO-BASED METHACRYLIC ACID AND OTHER ALKENOIC-DERIVED MONOMERS VIA CATALYTIC DECARBOXYLATION
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A novel method for the catalytic selective decarboxylation of a starting material to produce an organic acid is disclosed. According to at least one embodiment, the method may include placing a reaction mixture into a reaction vessel, the reaction mixture including a solvent, a starting material, and a catalyst, subjecting the reaction mixture to a predetermined pressure and temperature, and allowing the reaction to continue for 1-3 hours. The starting material may be at least one of a dicarboxylic acid, a tricarboxylic acid, and an anhydride of a dicarboxylic or tricarboxylic acid. As an exemplary embodiment, itaconic acid may be a starting material and the organic acid may be methacrylic acid. The predetermined temperature may be 250° C. or less, and the reaction pressure may be less than 425 psi. Further, a polymerization inhibitor may be used.
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Paragraph 0060-0061
(2018/04/26)
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- Methacrylic acid production method
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A method of producing methacrylic acid using a hydrotalcite catalyst and subcritical water is described.
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Page/Page column 9; 14-15
(2018/12/11)
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- COPOLYMER FOR COSMETICS, SURFACE TREATMENT AGENT FOR COSMETIC POWDER, POWDER FOR COSMETICS, AND COSMETIC PREPARATION
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The purpose of the present invention is to provide: a copolymer for cosmetics, which has excellent water repellency and oil repellency even though a polyfluoroalkyl group therein has 6 or less carbon atoms; a surface treatment agent which contains the copolymer for cosmetics; a powder for cosmetics, which is treated with the surface treatment agent and has excellent water repellency and oil repellency; and a cosmetic preparation which contains the powder for cosmetics. A copolymer for cosmetics of the present invention contains: 70-90% by mass of a constituent unit (A) that is derived from a compound represented by formula (a); 2-25% by mass of a constituent unit (B) that is derived from a compound represented by formula (b); 2-25% by mass of a constituent unit (C) that is derived from a compound represented by formula (c); 0.1-10% by mass of a constituent unit (D) that is derived from a compound represented by formula (d); and a residue (E) of a chain-transfer agent (e) that contains an OH group or a COOH group. [in-line-formulae]CH2═CR1—COO-Q1-Rf??(a)[/in-line-formulae] [in-line-formulae]CH2═CR2-Q2-COOH??(b)[/in-line-formulae] [in-line-formulae]CH2═CR3—COO—(R4O)n-R5??(c)[/in-line-formulae] [in-line-formulae]CH2═CR7—COO-Q3-P(O)(OH)—R8??(d)[/in-line-formulae]
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Paragraph 0052
(2014/08/19)
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- Synthesis of Bio-Based Methacrylic Acid by Decarboxylation of Itaconic Acid and Citric Acid Catalyzed by Solid Transition-Metal Catalysts
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Methacrylic acid, an important monomer for the plastics industry, was obtained in high selectivity (up to 84 %) by the decarboxylation of itaconic acid using heterogeneous catalysts based on Pd, Pt and Ru. The reaction takes place in water at 200–250 °C without any external added pressure, conditions significantly milder than those described previously for the same conversion with better yield and selectivity. A comprehensive study of the reaction parameters has been performed, and the isolation of methacrylic acid was achieved in 50 % yield. The decarboxylation procedure is also applicable to citric acid, a more widely available bio-based feedstock, and leads to the production of methacrylic acid in one pot in 41 % selectivity. Aconitic acid, the intermediate compound in the pathway from citric acid to itaconic acid was also used successfully as a substrate.
- Le N?tre, Jér?me,Witte-van Dijk, Susan C. M.,van Haveren, Jacco,Scott, Elinor L.,Sanders, Johan P. M.
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p. 2712 - 2720
(2016/12/23)
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- A PROCESS FOR THE PRODUCTION OF METHACRYLIC ACID AND ITS DERIVATIVES AND POLYMERS PRODUCED THEREFROM
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A process for the production of methacrylic acid by the base catalysed decarboxylation of at least one dicarboxylic acid selected from itaconic, citraconic or mesaconic acid or mixtures thereof is described. The decarboxylation is carried out at a temperature in the range from 100 to 199°C. A method of preparing polymers or copolymers of methacrylic acid or methacrylic acid esters is also described.
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Page/Page column 24
(2013/11/18)
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- PROCESS FOR THE PRODUCTION OF METHACRYLIC ACID AND ITS DERIVATIVES AND POLYMERS PRODUCED THEREFROM
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A process for the production of methacrylic acid is described. The process comprises the base catalysed decarboxylation of at least one or a mixture of dicarboxylic acids selected from itaconic, citraconic or mesaconic acid. The decarboxylation is carried out in the range greater than 240 and up to 275° C. to provide high selectivity. The methacrylic acid product may be esterified to produce an ester. A method of preparing polymers or copolymers of methacrylic acid or methacrylic acid esters using the process is also described. Optionally, the process may be preceded with a decarboxylation and, if necessary, a dehydration step on a source of pre-acid such as citric acid or isocitric acid.
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- PROCESS FOR RECOVERING ORGANIC COMPOUNDS FROM AQUEOUS STREAMS CONTAINING SAME
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A method for a liquid-liquid extraction of hydrophilic organic compounds from aqueous solutions thereof is described. The method generally includes intermixing a sufficient quantity of a specified glycol ether with the aqueous liquor at a first temperature to form a suspension comprising an aqueous raffinate phase and a glycol ether extract phase; separating the glycol ether extract phase from the aqueous raffinate phase; heating the glycol ether extract phase to a second, higher temperature to form a suspension comprising an aqueous extract phase containing a portion of the hydrophilic organic compound and a glycol ether raffinate phase; and separating this glycol ether raffinate phase from the aqueous extract phase. The selected glycol ether has an inverse solubility in water and the partition ratio, value K, for the hydrophilic organic compound is greater than 0.1. This method is useful for recovering valuable hydrophilic organic acids produced via fermentation or produced or used in various manufacturing processes.
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Page/Page column 15; 17
(2008/06/13)
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- Design and pharmacological activity of phosphinic acid based NAALADase inhibitors
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A novel series of phosphinic acid based inhibitors of the neuropeptidase NAALADase are described in this work. This series of compounds is the most potent series of inhibitors of the enzyme described to date. In addition, we have shown that these compounds are protective in animal models of neurodegeneration. Compound 34 significantly prevented neurodegeneration in a middle cerebral artery occlusion model of cerebral ischemia. In addition, in the chronic constrictive model of neuropathic pain, compound 34 significantly attenuated the hypersensitivity observed with saline-treated animals. These data suggest that NAALADase inhibition may provide a new approach for the treatment of both neurodegenerative disorders and peripheral neuropathies.
- Jackson,Tays,Maclin,Ko,Li,Vitharana,Tsukamoto,Stoermer,Lu,Wozniak,Slusher
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p. 4170 - 4175
(2007/10/03)
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- NMR Investigation of the Thermolysis of Citric Acid
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The thermolytic decomposition of citric acid in the presence of tin/lead solder has been investigated.The solid reaction products were first examined by solid-state 13C NMR.The samples were then dissolved in D2O, and 1H and 13C 1D and 2D (HMQC, TOCSY) spectra were obtained.Results indicate the presence of a series of compounds including 3-hydroxyglutaric, citraconic, itaconic and aconitic acids, and anhydrides.Solution- and solid-state NMR data are provided for citric acid and a number of metal and alkali metal citrate salts.Results of this work are related to the use of citric acid as a solder flux and to the elimination of chlorofluorocarbon cleaning processes in the electronics industry.Index Headings: NMR; Solid-state NMR; Citric acid; Thermolysis.
- Fischer, John W.,Merwin, Lawrence H.,Nissan, Robin A.
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p. 120 - 126
(2007/10/02)
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- Inhibitors of farnesyl protein transferase
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The present invention is directed to compounds which inhibit farnesyl-protein transferase (FTase) and the farnesylation of the oncogene protein Ras. The invention is further directed to chemotherapeutic compositions containing the compounds of this invention and methods for inhibiting farnesyl-protein transferase and the farnesylation of the oncogene protein Ras.
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- Process for the dyeing of leather with anionic dyes and polyaminoamide resin as dyeing auxiliary
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To improve the affinity of anionic dyestuffs in the dyeing of leather materials, polycondensation products consisting of at least one amine of the formula STR1 in which the radicals have the meanings mentioned in the description with one dicarboxylic acid and, if desired, ω-aminocarboxylic acid or its lactam are highly suitable.
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- Thermolysis of 7-Phenyl-2,3,7-triazabicyclooct-2-ene-6,8-dione
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Thermolysis of the title compound in boiling xylene (138 deg) produces a 7.7/10.1/1.0 mixture of the N-phenylimides of cis-1,2-cyclopropanedicarboxylic acid, citraconic acid, and itaconic acid.The imides of citraconic and itaconic acids are produced by hydrogen shifts.A completely concerted mechanism involving simultaneous hydrogen shift and cleavage of both C-N bonds is unlikely in the present case because both hydride-shift products are formed and because the optimal arrangement for the hydrogen shift requires deformation of the imide ring and loss of imide resonance.The C-N bond strengths in the title compound should be quite different.The products can arise either from two parallel pathways involving nitrogen-containing dipoles or from a single nitrogen-free trimethylene fragment.
- Majchrzak, Michael W.,Kotelko, Antoni
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p. 1475 - 1477
(2007/10/02)
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