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The synthesis of imidazolinium salts from low-cost amino alcohols incorporating different sterically demanding silyl groups is described. The new salts were analyzed and investigated as carbene precursors in a palladium-catalyzed asymmetric intramolecular a-arylation of an amide. The easily accessible carbene precursors gave enantiomeric excesses of up to 72% with nearly quantitative yields. The salts were also successfully applied as chiral solvating agents with the potassium salt of Mosher's carboxylate and can therefore contribute to the field of chiral recognition. [ABSTRACT FROM AUTHOR]

[Display omitted] • Transforming waste PET bottles into efficient PV membranes for bioethanol separation. • Computational analysis reveals PET membranes' stronger affinity for ethanol over water. • Waste-derived PET membranes compete well with conventional polymeric membranes. • Exploring energy-environment nexus to achieve key United Nations' sustainable goals. The use of bioethanol as an alternative source of fuel could solve energy and pollution concerns. However, its conventional recovery procedures make the overall process costly and energy intensive. Membrane-based pervaporation (PV) has gained significant attention in recent years. Most membranes that purify bioethanol are fabricated from conventional fossil-based polymers. This study presents the first work for biofuel separation by valorizing waste polyethylene terephthalate (PET) bottles into PV membranes. The performance of the membrane was characterized in terms of FTIR, XRD, TGA, WCA, SEM, and AFM and tested for a 10 wt% ethanol–water feed mixture at different temperatures. The mild hydrophobic character of PET allowed the PV membrane to achieve a separation factor of 10.45, a total flux of 1.7 kg m−2h−1, and a pervaporation separation index (PSI) of 18.72 at 45 °C. The recycled PET membrane (rPET) has higher mass transfer resistance for water compared to ethanol. The density functional theory (DFT) analysis confirms a stronger affinity of PET membrane towards ethanol than water. The results showed that rPET membranes have competitive performance compared to conventional fossil-based derived membranes. This study explores an energy-environment nexus approach, which could significantly contribute to achieving the key United Nations' sustainable development goals. [ABSTRACT FROM AUTHOR]

Efficiency of pristine and halogens doped graphdiyne analogue (GDY-28) is theoretically investigated for application as anode material in sodium ion batteries (NIBs). In this scenario, density functional theory (DFT) calculations are implemented to study electrochemical properties of Na/X@GDY-28 and Na+/X@GDY-28 (X = F−, Cl− and Br−) complexes in the presence of carbon tetracholride solvent. Na and Na+ prefer to adsorb in the middle of GDY-28 nanoflake. The adsorption energy (E ad) of Na+ is stronger as compared to Na for both pristine and halides doped GDY-28, E ad of Na + on GDY-28 in Na+@GDY-28 is −661.90 kcal mol−1. However, the calculated Gibbs free energy and cell voltage of pristine GDY-28 nanoflake are −3.82 kcal mol−1 and 0.17, respectively. Adopting a strategy of doping halides on GDY-28 nanoflake considerably increased the Gibbs free energy, which resulted in the enhancement of cell voltage. The cell voltage of these systems is increased from 0.17 V (for pristine GDY-28) to 0.20 V–0.52 V (for X−@GDY-28 (X− = F−, Cl− and Br−)). A monotonic increase in cell voltage is noticed with increase in electronegativity of halide ion. The reason is strong binding of Na+ with more electronegative halide ion doped GDY-28 nanoflake. The highest ΔG (−12.00 kcal mol−1) and cell voltage (0.52 V) is reported for Na/F@GDY-28 complex in the presence of carbon tetracholride. • The adsorption of sodium and sodium cation on graphdiyne (GDY-28) nanoflake is studied for Na-ion battery applications. • Halides doped GDY-28 nanoflake with surface adsorption of sodium/sodium cation is further investigated for enhancement in electrochemical properties. • Highly improved Gibb free energy and cell voltage are obtained for Na/F@GDY-28 complex i. e. of −79.23 kcal mol−1and 3.44 V, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • TM@Al 12 P 12 nanoclusters as single atom catalysts (SAC) toward OER. • Catalytic efficiency is investigated via DFT calculations. • Best catalytic efficiency is shown by Co@Al 12 P 12 complex. Global warming is an unparalleled challenge to the globe. The increased usage of fossil fuel has significantly increased the CO 2 level in the environment. Thus, scientists have diversified their attention towards other energy resources. Hydrogen energy represents a sustainable resource of green energy, where hydrogen and oxygen gases are converted into high amounts of energy without emitting greenhouse gases. In this work, we evaluated the potential use of transition metal (TM) doped Al 12 P 12 single atom catalysts (SACs) toward the oxygen evolution reaction (OER) on the basis of the density functional theory (DFT) calculations. Results have shown that the highest activity is realized by the Co@Al 12 P 12 SAC. This study represents another milestone in our quest of exploring the applicability of different TM@Nanocage systems as SACs for water electrolysis. We hope that this study will assist in the full realization of the water splitting reaction to produce hydrogen energy fuel. [ABSTRACT FROM AUTHOR]

Graphyne (GYN) has received immense attention in gas adsorption applications due to its large surface area. The adsorption of toxic ammonia and nitrogen halides gaseous molecules on graphyne has been theoretically studied at ωB97XD/6–31 + G(d, p) level of DFT. The counterpoise corrected interaction energies of NH3, NF3, NCl3, and NBr3 molecules with GYN are − 4.73, − 2.27, − 5.22, and − 7.19 kcal mol−1, respectively. Symmetry-adapted perturbation theory (SAPT0) and noncovalent interaction index (NCI) reveal that the noncovalent interaction between analytes and GYN is dominated by dispersion forces. The significant change in electronic behavior, i.e., energies of HOMO and LUMO orbitals and NBO charge transfer correspond to the pronounced sensitivity of GYN towards considered analytes, especially NBr3. Finally, TD-DFT calculation reveals a decrease in electronic transition energies and shifting of adsorption to a longer wavelength. The recovery time for NX3@GYN is observed in nanoseconds, which is many orders of magnitude smaller than the reported systems. The recovery time is further decreased with increasing temperature, indicating that the GYN benefits from a short recovery time as a chemical sensor. [ABSTRACT FROM AUTHOR]

[Display omitted] • Preparation of highly selective Choline Chloride based Deep Eutectic Solvent. • High CO 2 permeability for a supported DES based liquid membrane. • Supported liquid membranes showed excellent stability under different operating conditions. This study focuses on a forward looking approach in which deep eutectic solvents (DESs), a new class of designer solvents, were impregnated into micro porous polyvinylidene fluoride (PVDF) membrane for the separation of CO 2 from CH 4. Three types of DESs were prepared by mixing and heating of hydrogen bond acceptor (choline chloride) with either malic acid, tartaric acid or oxalic acid as hydrogen bond donor. The Fourier transform infrared spectroscopy confirmed the hydrogen bond interactions in the resulting DES. Thermal gravimetric analysis (TGA) was used to evaluate the thermal stability of the prepared membranes. The DES based supported liquid membranes were investigated systematically to determine the permeability and selectivity for the mixture of gases at both ambient and elevated temperatures. The results showed that Choline Chloride-Malic acid, Choline Chloride-Tartaric acid and Choline Chloride-Oxalic acid DES-SLMs exhibited CO 2 permeability of 30.32 Barrer, 34.00 Barrer and 37.30 Barrer, respectively while ideal selectivity of these membranes was found 51.39, 55.74 and 60.16 for CO 2 /CH 4 , respectively. The fabricated membranes were compared with some of the imidazolium supported ionic liquid membranes (SILMs) on the Robeson upper bound plot. The current study on DES-SLMs is expected to open new pathways for the exploitation of DESs for CO 2 capture. [ABSTRACT FROM AUTHOR]

[Display omitted] • Computational screening using COSMO-RS to select an optimal DES based on capacity and selectivity for ethanol dehydration. • Identification of the interactive sites between DESs and ethanol using DFT calculations. • Hydrogen bonding causes ethanol separation, as revealed by core-valance bifurcation (CVB) index analysis. Bioethanol has sparked significant interest as a promising energy source due to its green nature and sustainability. However, the separation of bioethanol presents considerable challenges. Deep eutectic solvents (DESs), as alternatives to conventional solvents, have shown efficient separation capabilities in various separation processes. However, selection of an ideal DES for a specific task always remains a challenge. In the present study, fifteen different hydrophobic DESs have been screened by employing COSMO-RS model. Three DESs (1,2-Decanediol: Thymol, Atropine: Thymol, and Lauric acid: Lidocaine) showing the best separation performance for ethanol from water were selected. DFT simulations have unveiled interaction mechanisms, emphasizing hydrogen bonding. Molecular electrostatic potential (MEP) analysis has identified the possible interaction sites for binding. Thermodynamic stabilities of the DES-ethanol complexes are elucidated through energy decomposition analysis (EDA) and second-order perturbation energies. Quantum theory of atoms in molecules (QTAIM) and interaction region indicator (IRI) analyses corroborate the existence of electrostatic interactions, predominantly in the form of hydrogen bonding, between ethanol and DESs. The significance of robust hydrogen bonding in driving ethanol separation is underscored through core-valence bifurcation (CVB) index analysis. The findings of this study yield a robust and practical methodology for choosing the most suitable DES, thereby enhancing the efficacy of ethanol separation from fermentation broths. This outcome offers a valuable and efficient approach that holds considerable promise for advancing the field of bioethanol production and refining processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A triple hybrid computational methodology is used to study modafinil drug derivatives. • Molecular docking was performed with ERα receptor to see potential interactions. • The complexes were further studied molecular dynamics simulations (120 ns). • The MMPBSA binding free energies were also calculated. • Structure-property relationship of compounds were predicted. Breast cancer (Bc a) is the prominent, most commonly detected, and the leading cause of mortality among women. Estrogen receptor alpha (ERα) is considered an important receptor for the proliferation of this disease and its blockage is necessary for the treatment of Bc a. The purpose of the current study is to design novel potential inhibitors against ERα of Bca. We designed modafinil drug derivatives using quantum chemical methods. These newly designed derivatives were put under an in-silico investigation followed by molecular docking simulation, molecular dynamics simulation, and MMPBSA analysis to find novel inhibitors of ERα. Moreover, three reference anticancer drugs; tamoxifen, raloxifene, and toremifene are also studied against ERα of Bc a. The spectroscopic and structural features of sulfoxide-based designed derivatives of modafinil drug M1 ((R)-2-(banzhydrylsulfinyl-N,N diethylacetamide) have been evaluated using different quantum chemical analyses. The findings of the current investigation demonstrate that all studied ligands exhibit the binding energy ranges (-5.3 to −5.8 Kcal/mol). The designed compounds showed effective hydrophobic (alkyl, π -alkyl, π -sigma, π -amide stacked, π - π T-shaped) interactions and hydrogen bond formation and are anticipated to be potential inhibitors against ERα. Additionally, designed derivatives have a good ADMET (absorption, distribution, metabolism, excretion, toxicity) profile and drug-likeness properties obeying RO5 without any toxicity. The stability profile of designed derivatives (M1 - M6) was further validated by molecular dynamics (MD) simulation and calculate binding free energy by the MM-PBSA approach. All ligand–protein complexes showed structural stability over the 120 ns MD simulation time. The MD simulation of the complex system was carried out by RMSD (root-mean-square deviation) of C α atoms of ERα, RMSF (root mean square fluctuations), R g (radius of gyration), SASA (solvent accessible surface area), and dynamic behavior of hydrogen bonds. The MD simulation results illustrate that RMSD for trajectories of designed derivative complexes over 120 ns are within the acceptable deviation range of ∼ 3 Å. The calculations of net binding free energy (Δ G b i n d ) between the designed derivatives and their complexes are found to be −8.50 Kcal/mol (M1) at maximum and −5.197 Kcal/mol (M3) at a minimum among all derivatives. The outcomes of our current in-silico investigation will evoke the scientific community to carry out further in vivo and in vitro studies on designed modafinil derivatives that can be potential therapeutic drug candidates against ERα. [ABSTRACT FROM AUTHOR]

[Display omitted] • Alkali metal substituted diamantanes are investigated for NLO response. • Alkali metal substitution increases first hyperpolarizability (upto 36,328 a.u.). • HOMO-LUMO gap is significantly reduced to 1.64 eV a.u. for K@CH a complex. • A bathochromic shift (λ max = 600 nm) is observed in the absorption spectrum. • Frequency dependent hyperpolarizabilities suggest sensitivity towards radiations. Electronic properties, absorption spectra and nonlinear optical properties of alkali metal substituted diamantanes are presented. A significant reduction in HOMO-LUMO gap has been observed by alkali metal substitution. K@CH a has the lowest H-L gap of 1.64 eV as compared to 8.88 eV for pristine diamantane. A remarkable increase in the first hyperpolarizability (β o) has been observed due to the substitution of alkali metals. Among these structures, K substituted complexes show the largest first hyperpolarizability (25526–36328 a.u). This significant increase in the first hyperpolarizability (β o) is attributed to low crucial transition energy (ΔE). K@CH a has the lowest ΔE value (2.06 eV) which results in the highest β o value (36328 a.u.) for K@CH a. Furthermore, frequency-dependent hyperpolarizability calculations have been carried out using 1906 nm and 1340 nm frequencies for commonly used lasers. The values of dynamic hyperpolarizabilities are greater than those of static ones for the majority of the substituted systems. This suggests the application of the proposed complexes under different frequencies of incident radiations. The substitution of alkali metals leads to the shift in absorption from ultraviolet to the visible region. Bathochromic shifts in the absorption spectra are observed with an increase in the size of alkali metal atom ( λ max = 600 nm for K@CH a). This study provides an efficient approach to design high-performance NLO materials having extensive applications in the field of electronics and optoelectronics. [ABSTRACT FROM AUTHOR]