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The electrochemical deposition of magnesium was investigated in ethereal Grignard salt solution with tetraethylammonium bistrifluoro-methanesulfonimidate additive, using cyclic voltammetry, potentiostatic transients, and scanning electron microscope measurements. The voltammograms showed the presence of reduction and oxidation peaks associated with the deposition and dissolution of magnesium. From the analysis of the experimental current transients, it was shown that the magnesium deposition process was characterized as a three-dimensional nucleation. The deposited product obtained from potentiostatic reduction presented a generally uniform and dense film.

In this work, dynamic viscosities of hydrocarbons and ionic liquids are studied. At high temperatures in these materials, a decrease in the value of dynamic viscosity was observed. Intermolecular interactions in the objects of study have been studied. It has been established that the intermolecular interaction in hydrocarbons is determined by the Born potential ($\phi \sim r^{-n})$. In this case, the temperature dependence of the dynamic viscosity of hydrocarbons is described by the law $\eta \sim T^{-m}$. It has been established that the dynamic viscosity of hydrocarbons in liquid form has a non-activating character. This occurs directly due to momentum transfer by phonons between adjacent layers located at a distance of nanometers.

The surface roughness growth of electrodeposited chromium films was investigated with a particular focus on the impact of water and an organic additive, acetylacetone, on the surface roughness scaling, the surface morphology, and microstructure. Cr-composite films were prepared by new deep eutectic solvent and deposited on Nickel substrate utilizing the electrodeposition technique. Acetylacetone sources enhanced nucleation at the initial deposition stage, and the surface roughness of the films was reduced noticeably. The surface structure was studied by profilometry and 3D optical microscope. The low average roughness values ($\sim$1.5$\mu$m) are achieved by adding water and acetylacetone, utilizing the novel ionic liquid. The most significant of the outcomes are associated with the role of water and acetylacetone which gives a reduction not only in $R_a$ but also in $R_z$ and $R_q$. The obtained outcomes are promising for Cr electrodeposition, which are capable of yielding hard chromium coatings with enhanced surface structure.

In this work, Langmuir films of organized assemblies of β-lactoglobulin (βLG) with 1-ethyl-3-methyl imidazolium ethyl sulfate (IL-emes) have been characterized at air/water interface using surface pressure-specific area isotherms and dilational rheology. The protein in the IL-mediated assembly shows excellent packing at the interface and is stable as seen in circular dichroic spectroscopy. These spread films on nickel chloride were transferred as Langmuir–Schaffer films of βLG and βLG+IL-emes and used as template for designing nanoclusters of nickel oxide. The nanoclusters have been characterized using transmission electron microscopy (TEM) and powder XRD. While pure protein template gives needle-shaped structures, the IL-mediated template gives spherical shapes of hexagonal nickel oxide in the range 30 nm to 40 nm. Presence of ionic liquid seems to slow down the growth of the cluster and also prevents aggregation of the clusters.

ONIOM studies were performed on the transition structure (TS) of organocatalytic direct aldol reaction by using ionic liquid supported benzoic acid (ILS-PhCO₂H) as an additive. Results obtained from this computation suggest direct involvement of ILS-PhCO₂H in the TS as a proton donor. It has also come out from the present study that, the counter ion of the ILS-acid additive may also play significant role to maintain the proper TS geometry by holding the organocatalyst and the acid additive close together during the course of reaction.

Large-scale molecular dynamics simulations consisting of more than 88,000–106,000 atoms for approximately 250 ns (including equilibration and production) were conducted to assess the effect of polar, nonpolar and amphiphilic molecular solvents on the nanoscale structuring of 1-$n$-dodecyl-3-methylimidazolium [C${}_{12}$mim] octylsulfate [C₈SO₄] ionic liquid (IL). Water [H₂O], $n$-octane [C₈H${}_{18}$] and 1-octanol [C₈H${}_{17}$OH] are employed as examples of polar, nonpolar, and amphiphilic molecules, respectively. The results indicate that each of these molecular solvents modify the nanosegregation behavior of the ionic liquid in a unique way. Water induces a high order of structuring of the ionic liquid as indicated by extremely high nematic order parameter for the system. In addition, the morphology of the neat ionic liquid is transformed from layer-like to that of bilayer-like in which the polar and nonpolar domains alternate. The presence of water also causes the stretching of the nonpolar domain, thus, increasing its size. At the concentration examined in this work, $n$-octane is found to be only partially miscible with the ionic liquid. The polar network is maintained; however, the continuous cationic nonpolar domain is split into multiple domains. $n$-octane is accommodated in the ionic liquid nonpolar domain. Similarly, the amphiphilicity of 1-octanol leads to an increase in the number of cationic as well as anionic domains. The overall nonpolar domain length, however, remains nearly identical to that found for the pure ionic liquid. Additional characterization of structural features of the three systems is discussed in terms of one-dimensional number densities, nematic order parameters for the overall systems and their components and structure factors.

For the steady-state behavior of diprotonated tetrakis(4-sulfonatophenyl)porphyrin (H₄TPPS^2-) in five imidazolium ionic liquids (ILs), the absorption positions of H₄TPPS^2- primarily depend on the constituent ions of the ILs whereas the emission positions of H₄TPPS^2- strongly depend on the polarity of the ILs. The fluorescence spectra of H₄TPPS^2- with different excitation wavelengths show no red-edge effect in our system. The dynamics of H₄TPPS^2- in ILs is further studied with a streak camera, and the relaxation process of ILs occurs on two different time scales. The short lived component attributed to the local motion of the cations and the anions around the porphine core varies from 32 to 196 ps. The long lived one originated from the collective diffusive motions of the cations and anions varies from 460 to 1072 ps. The average solvation time depends on the viscosity of the ILs. The rotational relaxation times of H₄TPPS^2- decrease as the viscosity of the ILs decreases.

The easy access and low price of pyrrole and aldehydes, conjugated with the simplicity in preparing meso-substituted porphyrins, makes this type of porphyrins very attractive for a broad range of applications. However, there is an increasing demand for the development of new synthetic processes involving more sustainable chemical principles substituting, whenever possible, dangerous organic solvents by alternative solvents, chromatographic purifications by precipitations and energy-intensive procedures by alternative energy sources such as microwaves and ultrasounds. In this review we will address some recent strategies to synthesize meso-substituted porphyrins using alternative energy sources, reaction media and catalysts, namely microwave irradiation, water as solvent, or solid microporous acid catalysts.

The structure of the most optimal acidic ionic liquids for the tetraphenylporphyrin synthesis was investigated, focusing on the cationic structure of ionic liquids. The investigation in [${\text{HC}}_{\text{n}}$im][CF₃CO₂] ($n$=1-12) with different lengths of alkyl groups at the N(1) position of imidazolium showed that the highest yield of tetraphenylporphyrin (20%) was obtained when the alkyl chain length was C8, which indicated that [HC₈im][CF₃CO₂] is the optimal ionic liquid for the tetraphenylporphyrin synthesis. In addition, we also investigated the influence of electron-withdrawing and electron-donating substituents at the C(2), C(4), and C(5) positions of the imidazolium cation of the acidic ionic liquids on the synthesis of tetraphenylporphyrins. The highest tetraphenylporphyrin yields were obtained in [HC₈mim][CF₃CO₂], which suggested that the imidazolium cation with an octyl group at the N(1) position and a methyl group at the C(2) position was the optimal structure.

We studied the interaction of water-soluble cationic metalloporphyrins, $p$Py and TMPyP, with the DNA double helix in ionic liquid solutions using CD and absorption spectra. The dispersibility of their porphyrin complexes was improved by electrostatic interactions of the anions of the ionic liquid. In the case of Cu(II) and Zn(II) complexes, the $p$Py complexes with pyridinium cations attached to the meso-phenyl groups via methylene groups intercalated into the DNA double helix, while the compact TMPyP complexes with pyridinium cations at the meso-position could not interact with DNA. Thus, it was suggested that the solvation behavior by ionic liquids depends on the structure of the porphyrin and also affects its interaction with DNA. Neither Mn(III) complexes with axial ligands could interact with DNA, regardless of the presence of the ionic liquids, due to their steric hindrance.

(Ionic liquids) ILs have unique properties compared with conventional solvents, opening a wide range of application as solvents and catalysts. ILs' cytotoxicity extend their application in biomedicine by acting as antimicrobial and anticancer agents. This article reviews the current research advances of ILs' biomedical application from the following four aspects: solvents, catalysts, antimicrobial and anticancer agents. By introducing ILs' interesting structures and their corresponding unique properties, this review concludes the current state-of-art of ILs biomedical applications. We also try to point out the ILs issues and solutions for more potential applications in biomedicine.

In this communication, we report the synthesis of an amino-functionalized ionic liquid (AFIL) and its application as building block in the construction of new functional nanomaterials. This AFIL has been used as surfactant in the synthesis of gold nanoparticles (Au NPs) and in the development of functional CNTs/IL hybrid nanomaterials by mixing the AFIL with multi-walled carbon nanotubes (MWCNTs). The presence of an amine group in the ionic liquid provides to the resultant nanomaterial with new opportunities in several applications in the nanobio field.

4-nitrophenol (4-NP) is a highly toxic pollutant for aquatic ecosystem and human life. Therefore, the catalytic reduction of 4-NP into useful 4-aminophenol (4-AP) is of interest. In this regard, two heterogeneous nanocatalysts, including Ag@HNTs-ILs and Co@HNTs-ILs were prepared by grafting imidazolium-based ionic liquids (ILs) onto the halloysite nanotubes (HNTs), followed by immobilization of Ag and Co nanoparticles (NPs), and characterized by means of FT-IR, SEM, EDX, TEM and XRD. The catalytic activity of the prepared nanocatalysts was evaluated for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) under environmentally friendly condition. A set of time, temperature, nanocatalyst amount and NaBH₄/4-NP molar ratios was screened. The reusability experiments demonstrated that Ag@HNTs-ILs and Co@HNTs-ILs were highly reusable, up to five reduction cycles without considerable changes in the reaction time. As the synthesized hybrid nanocatalysts could be re-collected and reused for various catalytic runs without any significant loss in their catalytic activity, they could be considered very promising nanomaterials from sustainability point of view.

Pristine graphene nanoflakes (GNFs) and those doped with nitrogen up to a level of 10.9at.% were tested as an electrode material for electrochemical double-layer supercapacitor. Doping with nitrogen increased the specific capacitance of GNFs from 88 to 180F/g. The increase results from the enhanced interaction of nitrogen-doped graphene layers with electrolyte ions.

N-ethyl-N-(2-methoxyethyl)-morpholinium bis(trifluoromethylsulfonyl)imide [Et(MEO)Mor][TFSI], N,N-bis(2-methoxyethyl)-morpholinium bis(trifluoromethylsulfonyl)imide [Bis(MEO)Mor][TFSI] and N,N-bis(2-methoxyethyl)-piperidinium bis(trifluoromethylsulfonyl)imide [Bis(MEO)Pip][TFSI] room-temperature ionic liquids (RTILs) were synthesized and their electrochemical properties were studied. Three stages of synthesis of RTILs were used, including the alkylation of secondary and tertiary amines and the anion exchange. The structure of RTILs was confirmed by ¹H, ${}^{13}$C, H,H-COSY, ¹H–${}^{13}$C correlation spectroscopy NMR and XPS. Three main approaches based on the Arrhenius, Litovitz, and Vogel–Fulcher–Tammann equations were used to analyze the ion transport properties of RTILs. In addition, the electrical conductivity of the binary acetonitrile solutions of RTILs was studied. It was found that the activation energy and conductivity of RTILs depended on their polarity and ability to associate which affects the mobility of charge carriers and viscosity of the system.

Polarizable molecular dynamics simulations are a fast progressing field in the scientific research of ionic liquids. The fundamentals of polarizable simulations, as well as their application to ionic liquids, were summarized in a review [Bedrov, D.; Piquemal, J.-P.; Borodin, O.; MacKerell, Jr., A. D.; Roux, B.; Schröder, C. Molecular Dynamics Simulations of Ionic Liquids and Electrolytes Using Polarizable Force Fields. Chem. Rev.2019, 119, 7940–7995] in 2019. Since then, new methods to treat intermolecular interaction of induced dipoles in these highly charged systems were developed. This concerns the damping of these interactions and additional charge transfer as well as the prediction of ionic materials with ultrahigh refractive indices. In addition to the progress of the polarizable force fields, also thermostats and barostats for polarizable simulations evolved recently.

Heterocyclic and fused heterocyclic compounds are ubiquitously found in natural products and biologically interesting molecules, and many currently marketed drugs hold heterocycles as their core structure. In this chapter, recent advances on Pd-catalyzed synthesis of heterocycles in ionic liquids (ILs) are reviewed. In palladium catalysis, ILs with different cations and anions are investigated as an alternative recyclable and environmentally benign reaction medium, and a variety of heterocyclic compounds including cyclic ketals, quinolones, quinolinones, isoindolinones, and lactones are conveniently constructed. Compared to the traditional methods, these new approaches have many advantages, such as environmentally friendly synthetic procedure, easy product and catalyst separation, recyclable medium, which make them have the potential applications in industry.

During the last two decades, supercritical CO₂ (scCO₂) emerged as an environmentally benign medium for sustainable chemical synthesis and catalysis. This chapter provides an overview of the applications of scCO₂ as an alternative for harmful organic solvents in chemical reactions. Special emphasis will be given to the importance of phase behaviour and on how scCO₂ unique properties can be successfully explored in the implementation of process intensification strategies.

The mechanism allowing a protein to search for a target sequence on DNA is currently described as an intermittent process made of 3D diffusion in bulk and 1D diffusion along the DNA molecule. Due to the relevant charge of protein and DNA, electrostatic interaction should play a crucial role during this search. In this paper, we explicitly derive the mean field theory allowing for a description of the protein-DNA electrostatics in solution. This approach leads to a unified model of the search process, where 1D and 3D diffusion appear as a natural consequence of the diffusion on an extended interaction energy profile.

Using the ionic liquid (IL) [(HSO3-B)2IM]HSO4 as a eco-friendly catalyst, a variety of 3- arylbenzo[ƒ]quinoline-1,2-dicarboxylates and their dehydro derivatives were synthesized by the reaction of naphthyl-2-amine, aromatic aldehydes and dimethyl but-2-ynedioate in acetonitrile at reflux by One-Pot method. The structure of new compounds was characterized by melting point, FT-IR, 1H NMR, elemental analysis. The influence of different catalysts and catalysts loading were investigated, and then the optimal reaction condition was obtained. A possible mechanism was also proposed. Furthermore, the recycling experiment of the catalyst was conducted and the green catalytic system can be recycled for four times with tiny decreases in yields and reaction rates. The present methodology offers several advantages such as mild conditions, excellent yields, ecofriendly and recyclable catalyst.