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deep eutectic solvent

Wei Liu, Fang Wang
In this study, acidic deep eutectic solvents (DESs) have been studied as catalyst in transesterification of soybean oil with methanol to produce biodiesel. p-Toluenesulfonic acid-based deep eutectic solvent (P-DES), composed of p-toluenesulfonic acid and choline chloride (1:3, mol/mol), was found to be an efficient transesterification catalyst for biodiesel production. The optimum conditions for the transesterification process were as follows: 8% P-DES catalyst, 8:1 molar ratio of methanol to oil, reaction temperature of 110℃ and 2 h reaction time...
August 14, 2018: Journal of Oleo Science
Nadia Guajardo, Pablo Domínguez de María
Deep eutectic solvents (DES) may become important alternatives as versatile, biodegradable, and cost-effective solvents for biocatalysis. Especially for reactions where substrates and products of different polarities are combined, the design of a tailored solvent that may dissolve all compounds-while being enzyme-compatible at the same time-appears to be a strong ally in sustainable chemistry. Herein it is shown that the combination of DES with "water as cosolvent" (in a range from 5% to 20% water, v/v) leads to non-conventional solvents with significantly reduced viscosity...
2018: Methods in Molecular Biology
Kai Wu, Ting Su, Dongmei Hao, Weiping Liao, Yuchao Zhao, Wanzhong Ren, Changliang Deng, Hongying Lü
Choline chloride-based deep eutectic solvents (DESs) exhibited remarkable activity in the cycloaddition of CO2 with propylene oxide (PO) in the absence of any additives under solvent- and metal-free conditions as well as recyclability.
August 13, 2018: Chemical Communications: Chem Comm
Juho Antti Sirviö
In this study, a deep eutectic solvent (DES [based on triethylmethylammonium chloride (TEMA) and imidazole]) was used as a reaction medium for cationization of cellulose fibers with trimethylglycine (betaine) hydrochloride in the presence of p-Toluenesulfonyl (tosyl) chloride. Cellulose betaine ester with a cationic charge up to 1.95 mmol/g was obtained at mild reaction conditions (four hours at 80 °C). The reaction was further demonstrated in the fabrication of cationic cellulose nanofibers (CCNFs) by a mild mechanical disintegration of cationized cellulose...
October 15, 2018: Carbohydrate Polymers
Panli Xu, Yuzhi Wang, Jing Chen, Xiaoxiao Wei, Wei Xu, Rui Ni, Jiaojiao Meng, Yigang Zhou
In this work, aqueous biphasic systems (ABSs) composed of ionic liquids (ILs) and deep eutectic solvents (DESs) were developed and utilized to efficiently extract DNA for the first time. Four kinds of ILs/DESs were mainly constituted by betaine/carboxylic acid and betaine/carbohydrates respectively. While another DES ([TBAB][PPG400]) was formed by polypropylene glycol 400 (PPG 400) and tetrabutylammonium bromide (TBAB). The phase-formation ability of the studied ABSs was evaluated by using [TBAB][PPG400]/(ILs/DESs) and [TBAB][PPG400]/inorganic salts...
November 1, 2018: Talanta
Yi-Ting Hsieh, Yan-Ru Liu
The self-aggregation of a surfactant in a deep eutectic solvent (DES) for electrodeposition is reported. The physical properties and electrochemical behavior of an anionic surfactant, sodium dodecyl sulfate (SDS), in a widely used DES, a choline chloride-urea mixture (ChCl-urea) were investigated. Based on surface tension and the conductivity measurements, the SDS micelles that were formed in the ChCl-urea system remained stable at higher temperatures, i.e., 90 ºC. Cyclic voltammetric and chronoamperometric data indicate that the addition of SDS to the DES may alter the nucleation and the growth processes that occur in the electrodeposition process...
August 7, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Patrycja Makoś, Andrzej Przyjazny, Grzegorz Boczkaj
The paper presents novel nonionic and hydrophobic deep eutectic solvents which were synthesized from natural compounds, i.e., thymol, ±camphor, decanoic and 10-undecylenic acids. Fundamental physicochemical properties of the synthesized deep eutectic solvents were determined, followed by their application as extractants in ultrasound-assisted dispersive liquid-liquid microextraction to isolate and enrich polycyclic aromatic hydrocarbons from aqueous samples characterized by a complex matrix. The final determination was carried out by gas chromatography-mass spectrometry...
July 27, 2018: Journal of Chromatography. A
Giuseppe Dilauro, Sergio Mata García, Donato Tagarelli, Paola Vitale, Filippo M Perna, Vito Capriati
Pd-catalysed Suzuki-Miyaura cross-couplings between (hetero)aryl halides (Cl, Br, I) and versatile, moisture-stable mono- and bifunctional potassium aryltrifluoroborates proceed efficiently and chemoselectively in air and under generally mild conditions, with a catalyst loading as low as 1 mol%, in the absence of additional ligands, and employing Na2CO3 as base, and the deep eutectic solvent (DES) choline chloride/glycerol (1:2) as a sustainable and environmentally responsible medium. Catalyst, base and DES have been easily and successfully recycled up to six times with an E-factor as low as 8...
August 3, 2018: ChemSusChem
Naader Alizadeh, Arash Ghoorchian
2,4,6-Trinitrotoluene (TNT) is known as one of the most used explosives and its detection is significant in the public security, human health and environmental protection. The fabrication of absorbance based optical sensors for TNT is a serious challenge due to poor selectivity and sensitivity. We reported the design and fabrication of a superselective hybrid optoelectrochemical sensor based on the electrochemical reduction of Meisenheimer complex in a deep eutectic solvent (DES) modified with n-butylamine (nBA) for determination of TNT...
August 1, 2018: Analytical Chemistry
Maja Molnar, Harshad Brahmbhatt, Vesna Rastija, Valentina Pavić, Mario Komar, Maja Karnaš, Jurislav Babić
A series of rhodanine derivatives was synthesized in the Knoevenagel condensation of rhodanine and different aldehydes using choline chloride:urea (1:2) deep eutectic solvent. This environmentally friendly and catalyst free approach was very effective in the condensation of rhodanine with commercially available aldehydes, as well as the ones synthesized in our laboratory. All rhodanine derivatives were subjected to 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging activity investigation and quantitative structure-activity relationship (QSAR) studies were performed to elucidate their structure-activity relationship...
July 29, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Maria Luisa Di Gioia, Monica Nardi, Paola Costanzo, Antonio De Nino, Loredana Maiuolo, Manuela Oliverio, Antonio Procopio
The development of novel synthetic routes to produce bioactive compounds starting from renewable sources has become an important research area in organic and medicinal chemistry. Here, we present a low-cost procedure for the tunable and selective conversion of biomass-produced furfural to cyclopentenone derivatives using a mixture of choline chloride and urea as a biorenewable deep eutectic solvent (DES). The proposed medium is a nontoxic, biodegradable, and could be reused up to four times without any unfavorable effect on the reaction yield...
July 28, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Qiang Yu, Aiping Zhang, Wen Wang, Long Chen, Ruxue Bai, Xinshu Zhuang, Qiong Wang, Zhongming Wang, Zhenhong Yuan
Here, the potential use of herbal residues of Akebia as feedstock for ethanol production is evaluated. Additionally, five deep eutectic solvents from hemicellulose-derived acids were prepared to overcome biomass recalcitrance. Reaction temperatures had more significant influences on solid loss and chemical composition than the molar ratios of choline chloride (ChCl) to derived acids. Glycolic acid resulted in the maximum levels of lignin, xylan and glucan removal, which were 60.0%, 100% and 71.5%, respectively, at 120°C with a 1:6M ratio of ChCl-glycolic acid...
January 2018: Bioresource Technology
Zhe Jiang, Jiugang Yuan, Ping Wang, Xuerong Fan, Jin Xu, Qiang Wang, Lianbing Zhang
Wool keratin is a kind of renewable protein which has great potential in environment-friendly materials. In this paper, the dissolution of wool fiber and the regeneration of wool keratin in the deep eutectic solvent (DES) of choline chloride-urea was detailed studied. The results showed that 35.1 mg wool completely dissolved in 1 g DES at 130 °C in 5 h. The polarizing microscope, scanning electron microscope (SEM) images along with the amino acid analysis suggested that the DES mainly dissolved the wool cortex layer...
July 26, 2018: International Journal of Biological Macromolecules
Shahram Seidi, Leila Alavi, Ali Jabbari
Cr(VI) has carcinogenic effects, so determination of trace amount of chromium in human body such as urine has a great deal of importance. In this work, a novel microextraction method was developed based on solidification of dispersed fine droplets (SDFD) of a low melting point deep eutectic solvent (DES), produced with the aid of sonication, for fast and efficient determination of Cr(VI) in urine samples. Cr(VI) contents of the human urine samples were first complexed using 1,5-diphenylcarbazone at pH ≈ 2...
July 24, 2018: Biological Trace Element Research
Kai Rong, Liang Huang, Hui Zhang, Junfeng Zhai, Youxing Fang, Shaojun Dong
Deep eutectic solvents are a class of green and sustainable solvents in chemical processes. An electrochemical method was developed to fabricate nanoporous gold electrodes by alloying and dealloying Au-Zn alloy in ZnCl2-urea deep eutectic solvent. The as-prepared active nanoporous gold electrodes facilitate the electrochemical detections of water pollutants with superior sensitivities.
August 7, 2018: Chemical Communications: Chem Comm
Wanda Mączka, Katarzyna Wińska, Małgorzata Grabarczyk, Barbara Żarowska
Due to its structural similarity, the α'-1'-hydroxyethyl-γ-butyrolactone obtained by reduction of (±)-α-acetyl-γ-butyrolactone may have a similar function in the body to γ-butyrolactone (GBL). In the work presented, biotransformation of α-acetyl-γ-butyrolactone by three Rhodotorula strains was performed obtaining enantiomerically enriched alcohol. The process was carried out in growing and resting cultures. We studied how both media composition and organic solvent volume affected stereoselectivity and effectiveness of biotransformation...
July 20, 2018: International Journal of Molecular Sciences
Yaqian Ma, Menghan Liu, Ting Tan, Aiping Yan, Lan Guo, Kun Jiang, Changheng Tan, Yiqun Wan
INTRODUCTION: Camellia oleifera flowers are rich in flavonoids, but there has been little attention on their application. A simple and reliable method for determining the content of flavonoids in C. oleifera flowers would be very helpful for the utilisation of agriculture resources. OBJECTIVE: To develop an efficient analytical method for the determination of flavonoids in C. oleifera flowers by high-performance liquid chromatography-ultraviolet (HPLC-UV) detection...
July 23, 2018: Phytochemical Analysis: PCA
Sarah S Takla, Eman Shawky, Hala M Hammoda, Fikria A Darwish
An undisputed trend in sample preparation at present is to meet the requirements of green chemistry especially in the field of natural products. Green technology continuously pursues new solvents to replace common organic solvents that possess inherent toxicity. Over the past two decades, non-ionic surfactants have gained enormous attention from the scientific community. The micelle-mediated extraction and cloud-point preconcentration (CPE) methods offer a convenient alternative to the conventional extraction systems...
September 14, 2018: Journal of Chromatography. A
Jing Chen, Yuzhi Wang, Xiaoxiao Wei, Panli Xu, Wei Xu, Rui Ni, Jiaojiao Meng
A novel ternary hydrosulphonyl-based deep eutectic solvent (THS-DES) comprised of choline chloride/itaconic acid/3-mercaptopropionic acid (molar ratio 2:1:1) was firstly synthesized. The composition, property and microscopic structure of the new magnetic adsorbent (THS-DES@M-GO) based on the THS-DES modified the magnetic graphene oxide (M-GO) was characterized by the system. Magnetic solid-phase extraction (MSPE) based THS-DES@M-GO was firstly researched for the removal of mercury (Hg2+ ) from water. Various influencing factors such as the mass of adsorbent, solution pH, initial Hg2+ concentration, the removal time and temperature had been systematically tested...
October 1, 2018: Talanta
Reza Aryan, Hamid Beyzaei, Masoomeh Nojavan, Fatemeh Pirani, Hojat Samareh Delarami, Mahmood Sanchooli
A facile and efficient catalyst- and oxidant-free multicomponent synthesis of a small library of highly substituted pyrido[2,3-d]pyrimidine derivatives is reported. The products were obtained within relatively short reaction times in good to excellent yields in the presence of deep eutectic solvents as media and promoters. Simple purification and reusability of the deep eutectic solvent were the other beneficial factors of the reported protocol. All of the synthesized derivatives were thoroughly screened for possible in vitro antibacterial and antifungal effects against twenty-two bacterial and three fungal pathogens...
July 19, 2018: Molecular Diversity
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