4480-83-5Relevant articles and documents
Synthesis and characterization of magnetic mesoporous Fe3O4@mSiO2-DODGA nanoparticles for adsorption of 16 rare earth elements
Li, Jingrui,Gong, Aijun,Li, Fukai,Qiu, Lina,Zhang, Weiwei,Gao, Ge,Liu, Yu,Li, Jiandi
, p. 39149 - 39161 (2018/12/02)
In this study, novel magnetic mesoporous Fe3O4@mSiO2-DODGA nanoparticles were prepared for efficiently adsorbing and recycling REEs. Fe3O4@mSiO2-DODGA was characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The adsorption behavior of Fe3O4@mSiO2-DODGA was investigated by ICP-OES. The results showed that the content of DODGA in the adsorbent was 367 μmol g-1. Fe3O4@mSiO2-DODGA exhibited the highest adsorption rates for 15 REEs, except Tm, in a 2 mol L-1 nitric acid solution. Among these elements, the adsorption rates for Nd, Sm, Eu, Dy, Ho, Yb, Lu, Y and Sc ranged from 85.1% to 100.1%. The desorption rates for all 16 REE ions reached their maximum values when 0.01 mol L-1 EDTA was used as the eluent. The desorption rates for Nd, Ce, Sm, Eu, Ho, Yb, Lu, Y, and Sc were 87.7-99.8%. Fe3O4@mSiO2-DODGA had high stability in 2 mol L-1 HNO3 and could be used five times without significant loss of adsorption capacity. Moreover, these nanoparticles had high selectivity, and their adsorption rate was not affected even in a high-concentration solution of a coexisting ion. Therefore, 8 REE ions (Nd, Sm, Eu, Ho, Yb, Lu, Y, and Sc) were selected for the study of adsorption kinetics and adsorption isotherm experiments. It was demonstrated that the values of Qe (equilibrium adsorption capacity) for Nd, Sm, Eu, Ho, Yb, Lu, Y, and Sc were 14.28-60.80 mg g-1. The adsorption of REEs on Fe3O4@mSiO2-DODGA followed the pseudo-second-order kinetic model, Elovich model and Langmuir isotherm model, which indicated that the adsorption process of Fe3O4@mSiO2-DODGA for REEs comprised single-layer adsorption on a non-uniform surface controlled by chemical adsorption. It was concluded that Fe3O4@mSiO2-DODGA represents a new material for the adsorption of REEs in strongly acidic solutions.
Efficient cyclodehydration of dicarboxylic acids with oxalyl chloride
Kantin, Grigory,Chupakhin, Evgeny,Dar'in, Dmitry,Krasavin, Mikhail
supporting information, p. 3160 - 3163 (2017/07/18)
Literature examples illustrating the use of oxalyl chloride to prepare dicarboxylic acid anhydrides are surprisingly limited. At the same time, we have discovered a method involving the use of this readily available reagent which allowed the preparation of novel cyclic anhydrides where other, more conventional, methods had failed. Herein, we demonstrate that the method is applicable to a wide diversity of substrates, delivers good to excellent yields of cyclic anhydrides without chromatographic purification and can be considered a synthetic tool of choice whenever dicarboxylic acid cyclodehydration is required.
Heterogeneous catalysts for the cyclization of dicarboxylic acids to cyclic anhydrides as monomers for bioplastic production
Rashed, Md. N.,Siddiki,Ali, Md. A.,Moromi, Sondomoyee K.,Touchy, Abeda S.,Kon, Kenichi,Toyao, Takashi,Shimizu, Ken-Ichi
, p. 3238 - 3242 (2017/07/28)
Cyclic anhydrides, key intermediates of carbon-neutral and biodegradable polyesters, are currently produced from biomass-derived dicarboxylic acids by a high-cost multistep process. We present a new high-yielding process for the direct intramolecular dehydration of dicarboxylic acids using a reusable heterogeneous Lewis acid catalyst, Nb2O5·nH2O. Various dicarboxylic acids, which can be produced by a biorefinery process, are transformed into the corresponding cyclic anhydrides as monomers for polyester production. This method is suitable for the production of renewable polyesters in a biorefinery process.
Room-temperature synthesis of pharmaceutically important carboxylic acids bearing the 1,2,4-oxadiazole moiety
Tarasenko, Marina,Duderin, Nikolay,Sharonova, Tatyana,Baykov, Sergey,Shetnev, Anton,Smirnov, Alexey V.
supporting information, p. 3672 - 3677 (2017/08/23)
An efficient and mild one-pot protocol has been developed for the synthesis of 1,2,4-oxadiazoles via the reaction of amidoximes with dicarboxylic acid anhydrides in a NaOH/DMSO medium. The method allows the synthesis of diversely substituted carboxylic acids bearing the 1,2,4-oxadiazole motif, – a popular building block for pharmaceutical research, in moderate to excellent yields. The reaction scope includes aromatic and heteroaromatic amidoximes as well as five-, six- and seven-membered anhydrides. The advantages of this procedure are proven gram-scalability and the use of inexpensive starting materials, which from a process chemistry point of view are essential for future industrial applications.
[A336][BDGA] ionic liquid and preparation method therefor
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Paragraph 0031; 0045, (2016/12/01)
The invention relates to [A336][BDGA] ionic liquid and a preparation method therefor and belongs to the field of synthesis of ionic liquid extractants. The preparation method comprises the following steps: (1) adopting isopropanol, sodium metal and methyl trioctyl ammonium chloride as reactants, dissolving the sodium metal in the isopropanol so as to produce sodium isopropoxide, then, subjecting sodium isopropoxide to reaction with methyl trioctyl ammonium chloride, and carrying out hydrolysis, so as to produce methyl trioctyl ammonium hydroxide; (2) adopting diglycolic acid, acetic anhydride and di-n-butylamine as reactants, firstly, dehydrating diglycolic acid so as to obtain diglycolic anhydride, and then, subjecting diglycolic anhydride to reaction with di-n-butylamine, so as to obtain N,N-di-n-butyl acetamido-oxy acetate; and (3) subjecting the quaternary ammonium hydroxide obtained in the step (1) and N,N-di-n-butyl acetamido-oxy acetate obtained in the step (2) to acid/base neutralization reaction, thereby obtaining the [A336][BDGA] ionic liquid product. The preparation method has the characteristics of short production cycle, low cost, high yield and high purity; and meanwhile, the [A336][BDGA] ionic liquid has a good rare-earth extracting and separating effect, thereby having a good market application prospect.
New Heterocyclic Product Space for the Castagnoli-Cushman Three-Component Reaction
Dar'In, Dmitry,Bakulina, Olga,Chizhova, Maria,Krasavin, Mikhail
supporting information, p. 3930 - 3933 (2015/08/18)
Significant expansion of heterocyclic product space accessible by the Castagnoli-Cushman reaction (CCR) has been achieved via the use of glutaric anhydride analogues containing endocyclic substitutions with oxygen, nitrogen, and sulfur. Incorporation of these heteroatoms in the anhydride's backbone results in enhanced reactivity and generally lower temperatures that are required for the reactions to go to completion. These findings are particularly significant in light of the CCR recently recognized as an efficient tool for lead-oriented synthesis.
METHOD FOR SYNTHESIZING RARE EARTH METAL EXTRACTANT
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Paragraph 0052, (2013/05/08)
A rare earth metal extractant containing, as the extractant component, dialkyldiglycol amide acid which is excellent in breaking down light rare earth elements is reacted in diglycolic acid (X mol) and an esterification agent (Y mol) at a reaction temperature of 70° C. or more and for a reaction time of one hour or more such that the mol ratio of Y/X is 2.5 or more, and is subjected to vacuum concentration. Subsequently, a reaction intermediate product is obtained by removing unreacted products and reaction residue, and an aprotic polar solvent is added as the reaction solvent. Then, the reaction intermediate product is reacted with dialkyl amine (Z mol) such that the mol ratio of Z/X is 0.9 or more and the aprotic polar solvent is removed. As a consequence, a rare earth metal extractant is efficiently synthesized at a low cost and at a high yield without having to use expensive diglycolic acid anhydride and harmful dichloromethane.
BIPHENYLAZETIDINONE CHOLESTEROL ABSORPTION INHIBITORS
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Page/Page column 204-205, (2008/06/13)
The invention relates to a chemical genus of 4-biphenyl-1-phenylazetidin-2-ones useful in the treatment of hypercholesterolemia and other disorders. The compounds have the general formula (I). Pharmaceutical compositions and methods for treating cholesterol- and lipid-associated diseases are also disclosed.
Synthesis of Small-Medium Ring Thioanhydrides
Kates, Michael J.,Schauble, J. Herman
, p. 971 - 978 (2007/10/02)
Reaction of five-membered ring anhydrides with sodium sulfide has previously been employed for synthesis of the corresponding thioanhydrides in low yields.Re-examination of the stoichiometry reveals reaction of cyclic anhydride with sodium sulfide (2:1 respectively), affords the thioanhydride accompanied by the corresponding dicarboxylate in a 1:1 molar ratio.The mechanistic pathway for this reaction has also been elucidated.Optimization of reaction conditions has resulted in the synthesis of a variety of four to seven-membered ring thioanhydride in yields approaching theoretical.
