13392-69-3Relevant academic research and scientific papers
Characterization of carboxylic acid reductases for biocatalytic synthesis of industrial chemicals
Kramer, Levi,Hankore, Erome Daniel,Liu, Yilan,Liu, Kun,Jimenez, Esteban,Guo, Jiantao,Niu, Wei
, p. 1452 - 1460 (2018)
Carboxylic acid reductases (CARs) catalyze the reduction of a broad range of carboxylic acids into aldehydes, which can serve as common biosynthetic precursors to many industrial chemicals. This work presents the systematic biochemical characterization of five carboxylic acid reductases from different microorganisms, including two known and three new ones, by using a panel of short-chain dicarboxylic acids and hydroxy acids, which are common cellular metabolites. All enzymes displayed broad substrate specificities. Higher catalytic efficiencies were observed when the carbon chain length, either of the dicarboxylates or of the terminal hydroxy acids, was increased from C2 to C6. In addition, when substrates of the same carbon chain length are compared, carboxylic acid reductases favor hydroxy acids over dicarboxylates as their substrates. Whole-cell bioconversions of eleven carboxylic acid substrates into the corresponding alcohols were investigated by coupling the CAR activity with that of an aldehyde reductase in Escherichia coli hosts. Alcohol products were obtained in yields ranging from 0.5 % to 71 %. The de novo stereospecific biosynthesis of propane-1,2-diol enantiomer was successfully demonstrated with use of CARs as the key pathway enzymes. E. coli strains accumulated 7.0 mm (R)-1,2-PDO (1.0 % yield) or 9.6 mm (S)-1,2-PDO (1.4 % yield) from glucose. This study consolidates carboxylic acid reductases as promising enzymes for sustainable synthesis of industrial chemicals.
Unusual Adsorption at the Air-Water Interface of a Zwitterionic Carboxybetaine with a Large Charge Separation
Ma, Kun,Li, Pei Xun,Dong, Chu Chuan,Thomas, Robert K.,Penfold, Jeffrey
, p. 3340 - 3347 (2016)
The structures of layers of three different dodecylcarboxybetaine surfactants adsorbed at the air-water interface have been determined by neutron reflection. The zwitterionic compounds differed in the length of the spacer separating the quaternary ammonium and carboxylate groups, which was (CH2)1, (CH2)4, or (CH2)8. The limiting area per molecule was found to be 45, 52, or 84 ?2, respectively, and compared reasonably with results from surface tension showing that the Gibbs prefactor is 1 in each case. Isotopic labeling was used to distinguish between the position of the alkyl and spacer groups in the layer. The spacer was found to be well-immersed in water for the (CH2)1 and (CH2)4 spacers but significantly above water for the (CH2)8 spacer. The distribution of the (CH2)8 spacer along the surface normal was found to be similar to that of the dodecyl group; i.e., it projects out of the water, contrary to an earlier hypothesis that it forms a loop. Comparison of the overlap of water with dodecyl and spacer groups also indicates that the (CH2)8 spacer is well out of the water. This in turn suggests that the anionic carboxylic acid group, which is dissociated in solution, is not ionized in the adsorbed layer. A further observation is that the dodecylcarboxybetaine with the (CH2)8 spacer reaches surface saturation at one-tenth of the critical micelle concentration. This is highly unusual and is attributed to the long spacer destabilizing the micelle relative to the surface layer.
Reactivity of lactones and GHB formation
Perez-Prior, M. Teresa,Manso, Jose A.,Del Pilar Garcia-Santos,Calle, Emilio,Casado, Julio
, p. 420 - 426 (2005)
(Chemical Equation Presented) The behavior of lactones in their hydrolysis reactions is a good indicator of their reactivity as electrophilic molecules. The hydrolysis of four- to six-membered lactones was investigated in neutral (water) and slightly acid media and in water/dioxane media. The following conclusions were drawn: (i) The reactivity of β-propiolactone in neutral water is more than four times greater than that of β-butyrolactone, due to the flow of charge caused by the latter's methyl substituent. Reactivity is enthalpy-controlled. (ii) The reactivity of β-lactones diminishes in water/dioxane media when the percentage of dioxane increases. The increase in the dioxane percentage relaxing the intermolecular hydrogen bonds in the ordered structure of the water reduces ΔH# and simultaneously increases the -ΔS# value. (iii) An inverse solvent kinetic isotope effect in the acid-catalyzed hydrolysis of γ-butyrolactone and δ-valerolactone was observed, this being indicative of acyl cleavage. (iv) The ΔH# and ΔS# values permit discrimination between alkyl and acyl cleavage, (v) A correlation was found between the chemical reactivity of lactones and their carcinogenic activity. (vi) The results suggest that orally ingested γ-butyrolactone remains largely in its nonhydrolyzed form in the stomach before passing into the blood. (vii) The concentration equilibrium constant of GHB formation at human body temperature is Keq (37°C) = 0.40. (viii) Study of GHB formation shows that, contrary to earlier results, this is an endothermic process, with ΔrH= 3.6 kJ mol-1.
Pentafluoroperbenzoic acid as the efficient reagent for Baeyer–Villiger oxidation of cyclic ketones
Khusnutdinov, Ravil I.,Egorova, Tatyana M.,Aminov, Rishat I.,Dzhemilev, Usein M.
, p. 644 - 645 (2018)
The Baeyer–Villiger oxidation of cyclic ketones with pentafluoroperbenzoic acid provides the corresponding lactones in 40–98% yields.
Lipase catalysed oxidations in a sugar-derived natural deep eutectic solvent
Vagnoni, Martina,Samorì, Chiara,Pirini, Daniele,Vasquez De Paz, Maria Katrina,Gidey, Dawit Gebremichael,Galletti, Paola
, (2021/05/06)
Chemoenzymatic oxidations involving the CAL-B/H2O2 system was developed in a sugar derived Natural Deep Eutectic Solvent (NaDES) composed by a mixture of glucose, fructose and sucrose. Good to excellent conversions of substrates like cyclooctene, limonene, oleic acid and stilbene to their corresponding epoxides, cyclohexanone to its corresponding lactone and 2-phenylacetophenone to its corresponding ester, demonstrate the viability of the sugar NaDES as a reaction medium for epoxidation and Baeyer-Villiger oxidation.
Hydrogenolysis of tetrahydrofuran-2-carboxylic acid over tungsten-modified rhodium catalyst
Asano, Takehiro,Nakagawa, Yoshinao,Tamura, Masazumi,Tomishige, Keiichi
, (2020/07/04)
Catalysts for reduction of tetrahydrofuran-2-carboxylic acid (THFCA), which can be synthesized from furfural via oxidation and hydrogenation, were explored among the combinations of noble metal and reducible metal oxide supported on SiO2. Rh-WOx/SiO2 catalysts showed activity in C-O hydrogenolysis at 2-position of THFCA (to δ-valerolactone and 5-hydroxyvaleric acid) and higher yield ratio of these C-O hydrogenolysis products to carboxylic acid hydrogenation products than other bimetallic catalysts. The activity of Rh-WOx/SiO2 catalysts was highest at W/Rh = 0.25 mol/mol. XRD, TPR, CO adsorption and XAFS characterizations showed that the Rh-WOx/SiO2 (W/Rh = 0.25) catalyst contained Rh metal particles with surface modification with isolated W2+ oxide species. The mechanism that hydride-like species formed on Rh atom attacks the C atom at the α-position (2-position) of adsorbed carboxylate on W atom is proposed based on the similar kinetics and similar catalyst structure to Rh-MOx/SiO2 (M = Re, Mo) which is known to be active in THFA hydrogenolysis to 1,5-pentanediol.
Production of Hydroxy Acids: Selective Double Oxidation of Diols by Flavoprotein Alcohol Oxidase
Fraaije, Marco W.,Martin, Caterina,Trajkovic, Milos
supporting information, p. 4869 - 4872 (2020/02/11)
Flavoprotein oxidases can catalyze oxidations of alcohols and amines by merely using molecular oxygen as the oxidant, making this class of enzymes appealing for biocatalysis. The FAD-containing (FAD=flavin adenine dinucleotide) alcohol oxidase from P. chrysosporium facilitated double and triple oxidations for a range of aliphatic diols. Interestingly, depending on the diol substrate, these reactions result in formation of either lactones or hydroxy acids. For example, diethylene glycol could be selectively and fully converted into 2-(2-hydroxyethoxy)acetic acid. Such a facile cofactor-independent biocatalytic route towards hydroxy acids opens up new avenues for the preparation of polyester building blocks.
One-pot biosynthesis of 1,6-hexanediol from cyclohexane by: De novo designed cascade biocatalysis
Kang, Lixin,Li, Aitao,Li, Qian,Li, Renjie,Wang, Fei,Yu, Xiaojuan,Zhang, Zhongwei,Zhao, Jing
, p. 7476 - 7483 (2020/11/23)
1,6-Hexanediol (HDO) is an important precursor in the polymer industry. The current industrial route to produce HDO involves energy intensive and hazardous multistage (four-pot-four-step) chemical reactions using cyclohexane (CH) as the starting material, which leads to serious environmental problems. Here, we report the development of a biocatalytic cascade process for the biotransformation of CH to HDO under mild conditions in a one-pot-one-step manner. This cascade biocatalysis operates by using a microbial consortium composed of three E. coli cell modules, each containing the necessary enzymes. The cell modules with assigned functions were engineered in parallel, followed by combination to construct E. coli consortia for use in biotransformations. The engineered E. coli consortia, which contained the corresponding cell modules, efficiently converted not only CH or cyclohexanol to HDO, but also other cycloalkanes or cycloalkanols to related dihydric alcohols. In conclusion, the newly developed biocatalytic process provides a promising alternative to the current industrial process for manufacturing HDO and related dihydric alcohols. This journal is
Aerobic oxidation of C4-C6 α,ω-diols to the diacids in base-free medium over zirconia-supported (bi)metallic catalysts
Mounguengui-Diallo, Modibo,Sadier, Achraf,Da Silva Perez, Denilson,Nikitine, Clémence,Puchot, Laura,Habibi, Youssef,Pinel, Catherine,Perret, Noémie,Besson, Michèle
, p. 9873 - 9885 (2019/07/04)
Oxidation of aliphatic α,ω-diols is a potentially interesting route to the production of valuable α,ω-diacids or ω-hydroxy acids for various polymer synthesis. 1,4-Butanediol (BDO), 1,5-pentanediol (PDO) and 1,6-hexanediol (HDO) are particularly attractive since they may be obtained from lignocellulosic biomass. The aqueous aerobic oxidation of these diols to the corresponding diacids was investigated in water over a set of Au, Pt, Au-Pt and Au-Pd catalysts supported on zirconia at 70 °C or 90 °C under 40 bar air. The nature of the metallic catalyst influenced the distribution of products as oxidation proceeded. The longer the carbon chain linking the terminal alcohol groups, the higher the yield of the diacid. The best yields of succinic acid, glutaric acid and adipic acid reached 83, 84 and 96% from BDO, PDO and HDO, respectively, over Au-Pt/ZrO2. There was some evidence of decarbonylation of the α,ω-hydroxyaldehyde at the early stage of the reaction. The presence of the hydroxyl substituent in 1,2,6-hexanetriol significantly slowed the oxidation rates compared with HDO. Besides, oxidation of PDO or HDO was highly selective to the ω-hydroxycarboxylate in moderate alkaline medium (NaOH/diol = 2) over Au/ZrO2 (90-93%).
Selective hydrogenolysis of 2-furancarboxylic acid to 5-hydroxyvaleric acid derivatives over supported platinum catalysts
Asano, Takehiro,Takagi, Hiroshi,Nakagawa, Yoshinao,Tamura, Masazumi,Tomishige, Keiichi
supporting information, p. 6133 - 6145 (2019/11/20)
The conversion of 2-furancarboxylic acid (FCA), which is produced by oxidation of furfural, to 5-hydroxyvaleric acid (5-HVA) and its ester/lactone derivatives with H2 was investigated. Monometallic Pt catalysts were effective, and other noble metals were not effective due to the formation of ring-hydrogenation products. Supports and solvents had a small effect on the performance; however, Pt/Al2O3 was the best catalyst and short chain alcohols such as methanol were better solvents. The optimum reaction temperature was about 373 K, and at higher temperature the catalyst was drastically deactivated by deposition of organic materials on the catalyst. The highest yield of target products (5-HVA, δ-valerolactone (DVL), and methyl 5-hydroxyvalerate) was 62%, mainly obtained as methyl 5-hydroxyvalerate (55% yield). The byproducts were mainly ring-hydrogenation compounds (tetrahydrofuran-2-carboxylic acid and its ester) and undetected ones (loss of carbon balance). The catalyst was gradually deactivated during reuses even at a reaction temperature of 373 K; however, the catalytic activity was recovered by calcination at 573 K. The reactions of various related substrates were carried out, and it was found that the O-C bond in the O-CC structure (1,2,3-position of the furan ring) is dissociated before CC hydrogenation while the presence and position of the carboxyl group (or methoxy carbonyl group) much affect the reactivity.
