Xi:Irritant;
97-65-4Relevant articles and documents
Efficient conversion of bio-renewable citric acid to high-value carboxylic acids on stable solid catalysts
Li, Zhaowei,Liu, Haichao,Wen, Xin
, p. 1650 - 1658 (2022/03/07)
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
The crystal structure of mouse IRG1 suggests that cis-aconitate decarboxylase has an open and closed conformation
Chun, Hye Lin,Lee, So Yeon,Kim, Ki-Hwa,Lee, Chang Sup,Oh, Tae-Jin,Ho Park, Hyun
, (2020/12/17)
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.
METHOD FOR THE PRODUCTION OF METHYLSUCCINIC ACID AND THE ANHYDRIDE THEREOF FROM CITRIC ACID
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Page/Page column 15, (2018/04/21)
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
BIO-BASED METHACRYLIC ACID AND OTHER ALKENOIC-DERIVED MONOMERS VIA CATALYTIC DECARBOXYLATION
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Paragraph 0060-0061, (2018/04/26)
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.
Methacrylic acid production method
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Page/Page column 9; 14-15, (2018/12/11)
A method of producing methacrylic acid using a hydrotalcite catalyst and subcritical water is described.
Highly selective one-step dehydration, decarboxylation and hydrogenation of citric acid to methylsuccinic acid
Verduyckt, Jasper,De Vos, Dirk E.
, p. 2616 - 2620 (2017/04/06)
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).
Synthesis of Bio-Based Methacrylic Acid by Decarboxylation of Itaconic Acid and Citric Acid Catalyzed by Solid Transition-Metal Catalysts
Le N?tre, Jér?me,Witte-van Dijk, Susan C. M.,van Haveren, Jacco,Scott, Elinor L.,Sanders, Johan P. M.
, p. 2712 - 2720 (2016/12/23)
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.
COPOLYMER FOR COSMETICS, SURFACE TREATMENT AGENT FOR COSMETIC POWDER, POWDER FOR COSMETICS, AND COSMETIC PREPARATION
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Paragraph 0052, (2014/08/19)
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]
PROCESS FOR THE PRODUCTION OF METHACRYLIC ACID AND ITS DERIVATIVES AND POLYMERS PRODUCED THEREFROM
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, (2013/11/19)
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.
A PROCESS FOR THE PRODUCTION OF METHACRYLIC ACID AND ITS DERIVATIVES AND POLYMERS PRODUCED THEREFROM
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, (2013/11/18)
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.
