88-14-2Relevant articles and documents
Kinetic and mechanistic analysis of oxidation of 2-furoic hydrazide by hexachloroirradate(IV) in a wide pH range
Yao, Haiping,Tian, Hongwu,Xu, Liyao,Xia, Yanqing,Zhou, Li,Liu, Chunli,Shi, Tiesheng
, p. 771 - 777 (2019)
Oxidation of 2-furoic hydrazide (FH) by hexachloroiridate(IV) ([IrCl6]2?) was studied kinetically in a wide pH range in aqueous solution of 1.0?M ionic strength. The oxidation reaction followed well-defined second-order kinetics: ? d[IrCl6 2?]/dt = k′[FH]tot[IrCl6 2?], where [FH]tot denotes the total concentration of FH and k′ stands for the observed second-order rate constants. The established k′–pH profile displays that k′ increases drastically with pH and a plateau region exists between pH 4 and 6. A stoichiometric ratio of Δ[FH]tot/Δ[IrCl6 2?] = 1/4?was revealed by spectrophotometric titrations. 1H NMR spectroscopic studies indicated that FH was cleanly oxidized to 2-furoic acid. The kinetic data suggest a reaction mechanism in which all the three protolysis species of FH react with [IrCl6]2? in parallel, forming the rate-determining steps. Two stabilized hydrazyl radicals are generated in the rate-determining steps, in which a single electron is transferred to [IrCl6]2?. The two hydrazyl radicals react rapidly in consecutive steps requiring 3?mol of Ir(IV) to form 2-furoic acid as the final product. Rate constants of the rate-determining steps were deduced through a simulation of the rate expression to the k′–pH dependency data. Values of these rate constants demonstrate that the three protolysis species of FH have a huge reactivity span, changing by about 109 times toward reduction in [IrCl6]2? and that FH can be readily oxidized in neutral and basic media. Rapid scan spectra and the measured activation parameters suggest that an outer-sphere electron transfer is probably taking place in each of the rate-determining steps. This is the first kinetic study on the oxidation reactions of FH and provides concurrently the protolysis constants of FH (pKa1 = 3.04 ± 0.08 and pKa2 = 11.6 ± 0.1) at 25.0?°C and 1.0?M ionic strength.
High performance of Au/ZTC based catalysts for the selective oxidation of bio-derivative furfural to 2-furoic acid 1
Centi, Gabriele,Cozza, Daniela,Giordano, Girolamo,Giorgianni, Gianfranco,Lanzafame, Paola,Migliori, Massimo,Papanikolaou, Georgia,Perathoner, Siglinda
, (2021)
Furfural is a platform bio-molecule for which is valuable to develop new green upgrading processes in biorefinery. We report here for the first time the high performance of Au/ZTC catalyst for the selective oxidation of furfural to 2-furoic acid, as first step to develop electrodes. The ordered nanostructure and high surface area of BEA structure replica ZTC allows to develop 3D-type electrodes. Au/ZTC catalyst shows higher performance than commercial Vulcan, used as reference conductive carbon in fuel cells. The weak acidity on ZTC avoids decarboxylation and esterification reactions, leading to about 90% of furfural conversion fully selectivity to 2-furoic acid.
Transformation of Thioacids into Carboxylic Acids via a Visible-Light-Promoted Atomic Substitution Process
Fu, Qiang,Liang, Fu-Shun,Lou, Da-Wei,Pan, Gao-Feng,Wang, Rui,Wu, Min,Xie, Kai-Jun
, p. 2020 - 2024 (2022/03/31)
A visible-light-promoted atomic substitution reaction for transforming thiocacids into carboxylic acids with dimethyl sulfoxide (DMSO) as the oxygen source has been developed, affording various alkyl and aryl carboxylic acids in over 90% yields. The atomic substitution process proceeds smoothly through the photochemical reactivity of the formed hydrogen-bonding adduct between thioacids and DMSO. A DMSO-involved proton-coupled electron transfer (PCET) and the simultaneous generation of thiyl and hydroxyl radicals are proposed to be key steps for realizing the transformation.
Biocatalytic transformation of furfural into furfuryl alcohol using resting cells of Bacillus cereus
Rodríguez M, Alejandra,Rache, Leidy Y.,Brijaldo, María H.,Romanelli, Gustavo P.,Luque, Rafael,Martinez, José J.
, p. 220 - 225 (2021/02/16)
The bioconversion of furfural to furfuryl alcohol is an attractive route in biomass valorization that could replace traditional contaminant methods. The use of whole cells has been explored for this purpose. Bacillus cereus without previous treatment with furanic compounds was used to selectively obtain furfuryl alcohol. Growing and resting cells were employed. Using growing cells of B. cereus, lower yields to alcohol were obtained because of furfural toxicity. However, employing resting cells it was possible to reach higher yields to furfuryl alcohol. Optimal operative conditions were studied: different concentrations of furfural, glucose and molybdenum, pH, and temperature. Thus, glucose (100 mM) and molybdenum (0.1 mM) were added to maintain cell biomass obtaining a yield to furfuryl alcohol close to 80% at 30 °C, pH 7.2 from 30 mM of furfural.
Valorization of furfural using ruthenium (II) complexes containing phosphorus-nitrogen ligands under homogeneous transfer hydrogen condition
Aguirre, Pedro,Aranda, Braulio,López, Vicente,Moya, Sergio A.,Parra-Melipán, Sebastián,Valdebenito, Gonzalo
, (2021/08/10)
In this paper, we report the catalytic activity of a series of ruthenium (II) complexes containing phosphorus-nitrogen bidentated (P-N) ligands in the hydrogenation of furfural via hydrogen transfer reaction using two hydrogen donor sources: 2-propanol in basic medium and formic acid under mild conditions. The results showed that all the ruthenium complexes studied are catalytically active in the hydrogenation of furfural by hydrogen transfer reaction; they showed 100% conversion with both hydrogen sources. However, selectivities towards the formation of furfuryl alcohol were better when formic acid was used. It was also found that the reaction studied in a basic medium competes with the Cannizzaro reaction, obtaining furfuryl alcohol and furoic acid in a 70/30 ratio; on the other hand, using formic acid as the hydrogen source yields furfuryl alcohol with 100% selectivity. Although formic acid can be used as a hydrogen source successfully. The optimal substrate/acid ratio was found to be 1:1, as a higher concentration of formic acid can cause catalyst decomposition. The yielded products, furfuryl alcohol and furoic acid, obtained from renewable sources, have multiple applications in the organic chemical industry, replacing or complementing similar fossil-derived products.
Hydrolysis of amides to carboxylic acids catalyzed by Nb2O5
Siddiki,Rashed, Md. Nurnobi,Touchy, Abeda Sultana,Jamil, Md. A. R.,Jing, Yuan,Toyao, Takashi,Maeno, Zen,Shimizu, Ken-Ichi
, p. 1949 - 1960 (2021/03/26)
Hydrolysis of amides to carboxylic acids is an industrially important reaction but is challenging due to the difficulty of cleaving the resonance stabilized amidic C-N bond. Twenty-three heterogeneous and homogenous catalysts were examined in the hydrolysis of acetamide. Results showed that Nb2O5was the most effective heterogeneous catalyst with the greatest yield of acetic acid. A series of Nb2O5catalysts calcined at various temperatures were characterized and tested in the hydrolysis of acetamide to determine the effects of crystal phase and surface properties of Nb2O5on catalytic performance. The high catalytic performance observed was attributed mainly to the facile activation of the carbonyl bond by Lewis acid sites that function even in the presence of basic inhibitors (NH3and H2O). The catalytic studies showed the synthetic advantages of the present method, such as simple operation, catalyst recyclability, additive free, solvent free, and wide substrate scope (>40 examples; up to 95% isolated yield).
Synthesis, biological evaluation and molecular docking studies of indeno [1, 2-c] pyrazol derivatives as inhibitors of mitochondrial malate dehydrogenase 2 (MDH2)
Ahmadi, Farzaneh,Engel, Matthias,Baradarani, Mehdi M.
, (2021/03/15)
Hypoxia inducible factor-1 (HIF-1) is a pivotal transcription factor, which is strongly correlated with the induction of angiogenesis, tumor survival, metastasis, and cell proliferation, making it a pivotal therapeutic target for solid tumor therapeutic agents. Herein, a new series of multi-functional chemical probes were designed including principal groups, viz. adamantyl and indene, at various locations of the parent compound LW6. Molecular docking studies were performed on the designed compounds and their relationship with HIF-1α and malate dehydrogenase 2 (MDH2). Inhibition of MDH2 by our compounds was expected to decrease the NADH level. Indeed, treatment of the breast cancer cell line 4T1 led to a strong reduction of the NADH concentration. The greatest reduction in NADH production in mitochondria was observed with (E)-3-(4-((3r, 5r, 7r)-adamantan-1-yl) phenoxy)-N-(5-(piperidine-1-carbonyl)-1, 4-dihydroindeno [1, 2-c] pyrazol-3-yl) acrylamide (18: IC50 = 59 nM), and has the best inhibitory potential under hypoxic conditions (MCF-7: IC50 = 57 nM). This compound also gave one of the highest docking “higher than the score obtained with LW6 in parallel (?31.63 kcal/mol) in the initial docking runs (PDB Code: 4WLO). Other related compounds with good yields were also synthesized from docking results, and all the synthesized compounds (14, 18, 22, 26, 29, 30) were evaluated in vitro on human adenocarcinoma cell lines.
Preparation method for producing furan ammonium salt by using 2-acetylfuran
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Paragraph 0031-0034; 0046-0049; 0061-0064; 0078-0081; 0093, (2021/06/23)
The invention discloses a preparation method for producing furan ammonium salt by using 2-acetylfuran. The preparation method comprises the following steps: preparation of furanone acid, generation of 2-methoxyamine-2-furanacetic acid through oximation, purification of oximation reaction liquid and ammonification treatment. 2-acetylfuran is used as a raw material, the furan ammonium salt is obtained through oxidation, oximation, extraction and ammonification operation, a compound catalyst is added in the oxidation process, and the reaction speed is further increased through addition of transition metal salt; the transition metal salt and the catalytic promoter are combined with each other, and the catalytic promoter is used for synergistically promoting the catalytic performance of the transition metal salt, so that the conversion rate of furanone acid is further improved.
Au-catalyzed electrochemical oxidation of alcohols using an electrochemical column flow cell
Suga, Tatsuya,Shida, Naoki,Atobe, Mahito
, (2021/02/09)
A novel green system for the electrochemical oxidation of alcohols is demonstrated using a column flow cell. Voltammetric analysis revealed that the oxidation of 1-phenylethanol and benzaldehyde are promoted by using both an Au-electrode and an alkaline medium. To conduct such reaction with a column flow cell, we developed a method to modify a carbon-fiber thread with Au nanoparticles. The column carbon-fiber thread electrode modified with Au nanoparticles showed a high surface area, enabling the efficient electrochemical oxidation of various alcohols.
Hydrogen-Binding-Initiated Activation of O?H Bonds on a Nitrogen-Doped Surface for the Catalytic Oxidation of Biomass Hydroxyl Compounds
Liu, Xin,Luo, Yang,Ma, Hong,Zhang, Shujing,Che, Penghua,Zhang, Meiyun,Gao, Jin,Xu, Jie
, p. 18103 - 18110 (2021/07/14)
Hydrogen binding of molecules on solid surfaces is an attractive interaction that can be used as the driving force for bond activation, material-directed assembly, protein protection, etc. However, the lack of a quantitative characterization method for hydrogen bonds (HBs) on surfaces seriously limits its application. We measured the standard Gibbs free energy change (ΔG0) of on-surface HBs using NMR. The HB-accepting ability of the surface was investigated by comparing ΔG0 values employing the model biomass platform 5-hydroxymethylfurfural on a series of Co-N-C-n catalysts with adjustable electron-rich nitrogen-doped contents. Decreasing ΔG0 improves the HB-accepting ability of the nitrogen-doped surface and promotes the selectively initiated activation of O?H bonds in the oxidation of 5-hydroxymethylfurfural. As a result, the reaction kinetics is accelerated. In addition to the excellent catalytic performance, the turnover frequency (TOF) for this oxidation is much higher than for reported non-noble-metal catalysts.
