497-25-6Relevant articles and documents
Ethylene carbonate production by cyclocondensation of ethylene glycol and urea in the presence of metal oxides and metal acetylacetonates
Lyadov,Kochubeev,Markova,Khadzhiev
, p. 852 - 856 (2016)
A promising method for the production of ethylene carbonate is the cyclocondensation of ethylene glycol and urea in the presence of a catalyst. In this study, the catalytic effect of oxides and acetylacetonates of various metals on the occurrence of this reaction has been examined. It has been shown that cobalt acetylacetonate is the most effective catalyst. The effect of reaction conditions (temperature, pressure, contact time, and catalyst concentration) on the main parameters of catalytic conversion has been studied.
1H and 2H NMR spectroscopic studies on the metabolism and biochemical effects of 2-bromoethanamine in the rat
Holmes,Caddick,Lindon,Wilson,Kryvawych,Nicholson
, p. 1349 - 1359 (1995)
Male Fischer 344 rats were dosed with 2-bromoethanamine hydrobromide (BEA, N = 6) or [1,1,2,2,-2H4]-bromoethanamine hydrobromide (BEA-d4, N = 6) at 150 mg/kg i.p. and urine was collected -24 to 0 hr pre-dose and at 0-2 hr, 2-4 hr, 4-8 hr and 8-12 hr post-dose (p.d.). Urine samples were analysed directly using 500 and 600 MHz 1H NMR and 92.1 MHz 2H NMR spectroscopy. The major observed effect of BEA treatment was the induction of transient elevations in urinary glutaric acid (GTA) and adipic acid (ADA) excretion lasting up to 24 hr p.d. Most of the GTA was excreted in the 0-8 hr p.d. with maximal rates of 100-120 μM/hr for each rat occurring between 4 and 8 hr p.d. in animals treated with BEA or BEA-d4. GTA and ADA were shown to be of endogenous origin as there was no detectable incorporation of the 2H label into either compound following treatment of rats with BEA-d4. Following BEA-treatment there was an initial decrease in the levels of urinary citrate, succinate, 2-oxoglutarate and trimethylamine-N-oxide. A subsequent recovery of citrate and succinate was noted following the onset of medullary nephropathy. The abnormal urinary metabolite profiles were similar to that observed in the urine of humans with glutaric aciduria type II (an inborn error of metabolism) caused by a lack of mitochondrial fatty acyl coenzyme A dehydrogenases indicating that BEA or its metabolites have similar metabolic consequences. The BEA metabolite aziridine was detected by 1H and 2H NMR spectroscopy of the urine 8 hr p.d. together with BEA itself and two novel metabolites 2-oxazolidone (OX) and 5-hydroxy-2-oxazolidone (HOX). The formation of OX requires the reaction of BEA with endogenous bicarbonate followed by a cyclisation reaction eliminating HBr. Dosing rats with authentic OX resulted in the excretion of HOX but did not cause glutaric or adipic aciduria indicating that either aziridine or BEA itself was responsible for the presumed defect in mitochondrial metabolism.
Gold (III) phosphorus complex immobilized on fibrous nano-silica as a catalyst for the cyclization of propargylic amines with CO2
Sadeghzadeh, Seyed Mohsen
, p. 216 - 223 (2016)
In this study, The HPG@KCC-1 NP was prepared through the ringopening polymerization of glycidol on the surface of KCC-1 to form HPG@KCC-1 and then HPG@KCC-1 NPs were functionalized using chlorodiphenylphosphine and phosphine-functionalized nanoparticles (HPG@KCC-1/PPh2) as a recyclable phosphorus ligand was obtained. Also, gold (III) complex of HPG@KCC-1/PPh2 ligand (HPG@KCC-1/PPh2/Au) was prepared which used for the cyclization of propargylic amines with CO2 to provide 2-oxazolidinones. High catalytic activity and ease of recovery from the reaction mixture using filtration, and several reuse times without significant losses in performance are additional eco-friendly attributes of this catalytic system.
PROCESS SULFONATION OF AMINOETHYLENE SULFONIC ESTER WITH CARBON DIOXIDE ADDITION TO PRODUCE TAURINE
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Paragraph 47-49, (2021/10/02)
A process for producing taurine, comprising mixing aminoethanol sulfate ester (AES) and a carbon dioxide, thus producing a reaction mixture, and heating the reaction mixture in the presence of a sulfite or a bisulfite, or combination thereof, such that taurine is formed.
Highly synergistic effect of ionic liquids and Zn-based catalysts for synthesis of cyclic carbonates from urea and diols
Cheng, Weiguo,Deng, Lili,Dong, Li,He, Hongyan,Li, Zengxi,Qian, Wei,Shi, Zijie,Su, Qian,Sun, Wenzhong
, (2020/08/06)
The development of stable and efficient catalysts is an attractive topic for green chemistry reactions under mild reaction conditions. In order to improve solvent-free synthesis of cyclic carbonates from urea and diols, a binary catalyst systems of Zn-based and different ionic liquids (ILs) were developed and examined in this study. The yield of ethylene carbonate (EC) could reach to 92.2% in the presence of C16mimCl/ZnCl2 catalyst. Through exploring the structure-activity relationships of cation and anion, it was confirmed that a synergistic effect of cation and anion of catalyst had important influences on urea alcoholysis. Additionally, the controlling step of EC synthesis reaction involving the elimination of an ammonia molecule from intermediates had been revealed by in situ FT-IR. This could afford a guided insight for synthesizing cyclic carbonates with high yield. Furthermore, a possible mechanism for the catalytic process was proposed based on DFT and the experimental results via FT-IR, 1H-NMR and 13C NMR analysis, which revealed that not only a probable synergistic effects of cation-anion matters, but also C(2)-H of ILs and Zn2+ played a key role in accelerating the reaction of urea alcoholysis. This catalytic mechanism study is to provide a preliminary basis to develop novel catalysts for cyclic carbonates from urea and diols through a green synthetic pathway.
