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Meticulous electrode design is pivotal in advancing greener and more sustainable electro‐organic synthesis practices. In this research, our team designed and synthesized a copper‐doped electrode on multiwalled carbon nanotubes (MWCNTs) and characterized it using Fourier transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDS), thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) analysis, X‐ray diffraction (XRD) analysis, X‐ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV) analysis. Subsequently, this electrode was utilized as a catalyst at the electrode surface, serving as a cathode in electro‐oxidation reactions in the presence of phenylacetylene, sodium azide (NaN3), and benzyl halide for the production of 1,2,3‐triazole derivatives under ambient temperature, within a 30‐min reaction time, and at atmospheric pressure, achieving an efficiency level ranging from good to excellent, specifically between 88% and 96%. The synthesized 1,2,3‐triazole derivatives were identified using proton nuclear magnetic resonance (1H NMR) spectroscopy, CHN elemental analysis, and melting point. In this paper, choline chloride/urea deep eutectic solvents (DES) serve multiple roles in the reaction mechanism. They function as solvents and co‐catalysts, generate weak bases, and provide numerous advantages in green chemistry. These advantages include low toxicity, reduced environmental risks, improved atom economy, and non‐volatility, making them safer alternatives to traditional organic solvents. [ABSTRACT FROM AUTHOR]

In this study, choline chloride/urea was used as a green deep eutectic solvent in the three-component reaction of hydrazine/phenylhydrazine, malononitrile, and aromatic aldehydes for synthesizing pyrazole derivatives, and in the four-component reaction of methyl/ethyl acetoacetate, hydrazine/phenylhydrazine, malononitrile, and aromatic aldehydes for synthesizing pyrano[2,3-c]pyrazole derivatives. Elemental analysis, ¹H, and 13C NMR spectroscopy were used to confirm the structure of the synthesized pyrazole and pyrano[2,3-c] pyrazole derivatives. The antimicrobial effects of the synthesized pyrazole and pyrano[2,3-c] pyrazole derivatives were investigated. In antimicrobial tests, instructions from clinical and laboratory standards institutes were used. Antimicrobial study was done on pathogenic gram-positive and gram-negative species, and specialized aquatic strains and fungal species. Using choline chloride/urea, novel pyrazole derivatives and pyrano[2,3-c]pyrazole derivatives were synthesized, and other derivatives were synthesized with higher efficiency in less time than some previously reported methods. MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) obtained for derivatives were higher than some antibiotic drugs. Synthesis and reports of new derivatives of pyrazole and pyrano[2,3-c]pyrazole, and investigation and reports of their antimicrobial properties on gram-positive, gram-negative, and specialized aquatic and fungal species are among the novel and important findings of this study. [ABSTRACT FROM AUTHOR]

The simple pseudo four-component reaction of 2,7-naphthalenediol, tow molecules of aldehydes and ammonum carboxylates to produce a series of N-acylated and non-acylated highly substituted piperidine derivatives has been carried out in the presence of choline chloride/urea at 80 °C. One-pot reaction, high efficiency, appropriate reaction time, and easy purification of products by simple recrystallization are some of the considerable advantages of this procedure. The produced highly substituted piperidine derivatives were screened for their antioxidant property. The results indicated that the highly substituted piperidine derivative 4h had higher antioxidant properties. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) are eutectic mixtures of substances with the melting points considerably lower than those for their individual components. The study of various properties of DESs is currently attracting great attention due to the possibilities of their use as solvents in a wide variety of technological fields. In this work, it is shown using a choline chloride/urea mixture (1:2) that the method of pulsed spin-probe EPR can be used to study low-temperature stochastic molecular librations in DESs. A peculiarity of this type of motion is its sensitivity to the nanostructure of the substance under study. The studies carried out in this work showed that the choline chloride/urea mixture (1:2) exhibits a glass transition considerably broadened in temperature and starting below macroscopic glass transition. This broadening indicates that its nanostructure is rather loosely packed. [ABSTRACT FROM AUTHOR]

This work presents one‐pot synthesis of symmetric organic carbonates and ureas by employing cheap and biodegradable deep eutectic solvent as the catalyst and reaction media. The effect of different reaction parameters such as temperature, DMC/amines and alcohols ratio and reaction time were investigated on the reaction efficiency. This new protocol provides a simple, fast, and sustainable approach and proceeds with high efficiency with aliphatic and aromatic amines and alcohols as well. Finally, applicability of this methodology was also examined for reaction of nucleophiles such as phenyl hydrazine and phenyl glycine with dimethyl carbonate. Interestingly, it was found that this reaction system obtained good yields of product for both of them. [ABSTRACT FROM AUTHOR]

N-Unsubstituted cyclic imides were readily synthesized in deep eutectic solvent (DES) choline chloride (ChCl)/urea from anhydrides with urea. Urea serves as both a DES component and a nitrogen source, which endows the protocol with advantages of smooth reaction, easy separation of products, simple recovery and recycling of ChCl/urea. [ABSTRACT FROM AUTHOR]

The present study is aimed at solving the problem of poor solubility of the antituberculosis drug thioacetazone (TAZ), the use of which, despite its effectiveness, is limited by toxicity and requires a reduction of the therapeutic dose. Such representatives of "green chemistry" as a deep eutectic solvent based on choline chloride with urea, native and modified cyclodextrins (β-CD and HP-β-CD) and biocompatible polymers (PVP and PEG) were used as solubilizing agents. DES and modified HP-β-CD proved to be the most effective, improving water solubility of TAZ by 106 and 24 times, respectively. β-CD and polymers showed a weak solubilizing potential, demonstrating the ineffectiveness of their application to reduce the hydrophobicity of the drug. In addition, the effect of temperature and concentration of excipients in an aqueous medium on drug dissolution was studied. The thermodynamic aspects of the dissolution and complex formation processes of in the selected systems are also characterized. [Display omitted] [ABSTRACT FROM AUTHOR]

This study focused on the pretreatment with deep eutectic solvent of choline chloride (ChCl)/urea mixtures on rice straw and its chemical fractions of holocellulose, α-cellulose, and acid-insoluble-lignin (AIL). The pretreatment of ChCl/urea was significantly affected by the treated temperature prior to the treated time, and 130 °C and 4 h was an optimum condition for ChCl/urea pretreatment. The separation capacity of ChCl/urea on the chemical fractions was in an order of AIL (22.87%) > hemicellulose and amorphous cellulose (16.71%) > α-cellulose (9.60%). ChCl/urea had a higher selective solubility on lignin. The solubility of the whole fractionation of rice straw affected by ChCl/urea was a combination of solubilization on cellulose, hemicellulose and lignin. ChCl/urea pretreatment increased crystallinity index ( CrI ) of rice straw residue and α-cellulose, while had no obvious influence on CrI of holocellulose. The effect of structural properties of rice straw residue on enzymatic hydrolysis was also explored. [ABSTRACT FROM AUTHOR]

Agarose films were formed with the addition of 30 to 70 wt% choline chloride/urea eutectic-based ionic liquid (ChCl/Urea). The ChCl/Urea was prepared through complexation at a 1:2 mole ratio. The films were prepared by dissolving ChCl/Urea in distilled water followed by dispersion of the agarose at 95 °C. The solution was gelled at room temperature, and the formed gel was dried in an oven overnight at 70 °C. Mechanical testing indicated that the agarose film containing 60 wt% ChCl/Urea had higher tensile extension and tensile strain at break compared to the pristine agarose film. The addition of ChCl/Urea also reduced the glass transition temperature (Tg) of agarose films. Cross-section SEM images of the agarose films showed that surface roughness disappeared with the incorporation of ChCl/Urea. FTIR spectra confirmed the presence of intermolecular hydrogen bonding between agarose and ChCl/Urea. XRD patterns demonstrated that an amorphous phase was obtained when ChCl/Urea was added. Agarose films containing more ChCl/Urea exhibited higher transparency, as measured by a UV-Vis spectrometer. In summary, the physicochemical properties of agarose films were evidently affected by the incorporation of the ChCl/Urea as a plasticizing agent.

A sequential three-component reaction of aromatic aldehydes with MeUlrum's acid and N-methyl indole in the presence of choline chloride / urea ionic liquid as green catalyst has been described. In this one-pot multicomponent reaction, a series of indole-3-propanamide derivatives were synthesized with good to excellent yields. This methodology shows several advantages including fast reaction, easy isolation, operational simplicity that make it a useful and attractive option for the library generation of indole-3-propanamides (5a-l) for drug discovery. [ABSTRACT FROM AUTHOR]

Electrodeposition of palladium from a non-aqueous electrolyte solution [choline chloride/urea/palladium(II)chloride] has been carried out by direct and pulse current electroplating. In this study, the influence of an organic additive (nicotinic acid amide), current mode (direct current or pulse current deposition) and hydrodynamic on the surface morphology of electroplated palladium films was investigated. In order to determine the surface morphology and thickness of the electrodeposited palladium layers, a scanning electron microscope and an energy dispersive X-ray fluorescence spectroscope were used. In addition, the cell voltage during the different electrodeposition experiments was recorded and analysed. The experimental results showed that the surface morphology of the palladium deposits could be remarkably affected either by addition of the additive or by applying pulse current. Pulse plating and the selected inhibitor mutually interfere with each other, causing changes in the microstructure of the palladium deposits (e.g. smoothening or forming of micro-cracks). It was possible to optimise the palladium deposit quality by applying pulse current or by addition of the appropriate inhibitor. [ABSTRACT FROM AUTHOR]

The physical and electrochemical characteristics such as density, viscosity, electrical conductivity and cyclic voltammetry of three different non-aqueous palladium electrolytes were analysed. The cyclic voltammetry behaviour showed typical reduction and oxidation peaks corresponding to the deposition and stripping of palladium in the electrolytes employed. The electrodeposition of palladium films from choline chloride/ethylene glycol (ChCl-EG), choline chloride/urea (ChCl-urea) and 1-butyl-3-methylimidazolium chloride-tetrafluoroborate (BMIM-Cl-BF4) solutions was demonstrated. Compact deposits were obtained with galvanostatic electrolysis. The scanning electron micrographs of the deposits revealed predominantly nodular Pd particles. [ABSTRACT FROM AUTHOR]

Agarose films were formed with the addition of 30 to 70 wt% choline chloride/urea eutectic-based ionic liquid (ChCl/Urea). The ChCl/Urea was prepared through complexation at a 1:2 mole ratio. The films were prepared by dissolving ChCl/Urea in distilled water followed by dispersion of the agarose at 95 °C. The solution was gelled at room temperature, and the formed gel was dried in an oven overnight at 70 °C. Mechanical testing indicated that the agarose film containing 60 wt% ChCl/Urea had higher tensile extension and tensile strain at break compared to the pristine agarose film. The addition of ChCl/Urea also reduced the glass transition temperature (Tg) of agarose films. Cross- section SEM images of the agarose films showed that surface roughness disappeared with the incorporation of ChCl/Urea. FTIR spectra confirmed the presence of intermolecular hydrogen bonding between agarose and ChCl/Urea. XRD patterns demonstrated that an amorphous phase was obtained when ChCl/Urea was added. Agarose films containing more ChCl/Urea exhibited higher transparency, as measured by a UV-Vis spectrometer. In summary, the physicochemical properties of agarose films were evidently affected by the incorporation of the ChCl/Urea as a plasticizing agent. [ABSTRACT FROM AUTHOR]

A novel synthetic method was developed to prepare new fluorescent 2-(1,3-benzoxazol/benzothiazol-2-yl)-3H-benzo [f]chromen-3-one derivatives by the Knoevenagel condensation between 2-hydroxy-1-naphthaldehyde and benzothiazole-2-yl-aceatates or N-methyl benzoxazole-2-yl-acetates using choline chloride/urea ionic liquid as a green catalyst. The results of fluorescence studies revealed that all the compounds show moderate to low emission intensities and are expressed in the form of quantum yields. [ABSTRACT FROM AUTHOR]

The influence of choline chloride/urea ionic liquid in solid phase on the Knoevenagel condensation is demonstrated. The active methylene compounds such as meldrum's acid, diethylmalonate, ethyl cyanoacetate, dimethylmalonate, were efficiently condensed with various salicylaldehydes in presence of choline chloride/urea ionic liquid without using any solvents or additional catalyst. The reaction is remarkably facile because of the air and water stability of the catalyst, and needs no special precautions. The reactions were completed within 1hr with excellent yields (95%). The products formed were sufficiently pure, and can be easily recovered. The use of ionic liquid choline chloride/urea in solid phase offered several significant advantages such as low cost, greater selectivity and easy isolation of products. [ABSTRACT FROM AUTHOR]

Choline chloride/urea (1:2) is the most widely used deep eutectic solvent, which has attracted much attention due to its excellent advantages of low cost, environment friendly and easy synthesis. In this work, nanofriction-based molecular dynamics simulations were performed to investigate the effect of interfacial hydrophilicity on the flow resistance of Choline chloride/urea (1:2) confined in ionic model nanoslits. Simulation results showed that the flow resistance of the choline chloride/urea system increases with the increasing interfacial hydrophilicity. Urea molecules form a preferential adsorption layer on the wall. As the interfacial hydrophilicity increases, the number of urea molecules in the interfacial adsorption layer increased, whereas the stability decreased. Unique confined spatial distributions of urea molecules greatly contribute to ionic association between choline cations and chloride anions. Furthermore, with the increase of interfacial hydrophilicity, orientation distributions of urea molecules in the adsorption layer are more orderly, then causing a decrease in the average hydrogen bond number (N HB) of urea molecules. Moreover, the more the N HB of urea molecules, the better is the stability in the interfacial adsorption layer, which in turn results in less flow resistance. [ABSTRACT FROM AUTHOR]

Conductive paper has the advantages of being low-cost, lightweight, disposable, flexible, and foldable, giving it promising potential in future electronics. However, mainstream conductive papers are opaque and rigid, which seriously affect the wide application of conductive paper. In this paper, we demonstrate a highly transparent, flexible, and conductive paper, fabricated by mixing cellulose nanofibers (CNFs) with silver nanowires (AgNWs) and then plasticizing with choline chloride/urea solvent. The as-prepared CNF/AgNW paper showed high transparency (~90% transmittance) and flexibility (~27% strain), and low sheet resistance (56 Ω/sq). Moreover, the resistance change of CNF/AgNW paper increased only ~1.1% after 3000 bending−unbending cycles under a 150° large angle, implying a long working life and stability. In view of this, our methodology has the potential to open a new powerful route for fabrication of paper-based green electronics. [ABSTRACT FROM AUTHOR]