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This study investigated techniques of coating zeolitic imidazolate framework-8 (ZIF-8) particles on the surface of blocks of pine (Pinus densiflora) and a method for effectively preventing termite access. ZIF-8 was synthesized by the reaction of 2-methylimidazole (2-MeIm) and Zn2+ in methanol media. Treatment of the wood blocks was carried out by immersing wood blocks in aqueous dispersions of ZIF-8 (0.1–0.3%) and in aqueous solutions of 2-MeIm (0.01–0.3%). Subterranean termite (Reticulitermes speratus) prevention experiments were carried out using choice and no-choice tests according to AWPA standard (E1-17). In the no-choice test, termites would not eat the wood block treated with aqueous dispersions of ZIF-8 prepared at a concentration of 0.1% or more, and all died within 28 days of the experiment, 100% mortality. In the choice test performed for 28 days, the termites did not eat the treated block and ate only the untreated wood block and showed the same low mortality as the control group, and there was no damage to the treated wood block. The results of experiments performed with wood blocks treated with 2-MeIm aqueous solutions were similar to those of ZIF-8. In conclusion, ZIF-8 and 2-MeIm showed very effective anti-termite agent performance. [ABSTRACT FROM AUTHOR]

Two novel structure directing agents (NH 4 BF 4 and NH 4 HF 2) and six metal species of Al, Mn, Co, Ni, Cu and Zn are coupled to synthesize metal organic framework derivatives for energy storage. The Ni-HBF shows the highest specific capacitance of 698.0F/g at 20 mV/s. [Display omitted] • Metal organic framework derivatives are made by 2-methylimidazole, NH 4 BF 4 and NH 4 HF 2. • Metals of Al, Mn, Co, Ni, Cu and Zn are used to make materials for energy storage. • Ni-based derivative shows a highest specific capacitance (C F) of 698.0F/g (20 mV/s). • Device with Ni-based electrode has maximum energy density of 27.9 Wh/kg at 325 W/kg. • A C F retention of 170.9% and Coulombic efficiency of 93.2% are got in 10,000 cycles. Tailoring morphology and composition of metal organic frameworks (MOF) can improve energy storage by establishing high surface area, large porosity and multiple redox states. Structure directing agents (SDA) is functional of designing surface properties of electroactive materials. Ammonium fluoride has functional abilities for designing MOF derivatives with excellent energy storage abilities. Systematic design of MOF derivatives using ammonia fluoride-based complex as SDA can essentially create efficient electroactive materials. Metal species can also play significant roles on redox reactions, which are the main energy storage mechanism for battery-type electrodes. In this work, 2-methylimidazole, two novel SDAs of NH 4 BF 4 and NH 4 HF 2 , and six metal species of Al, Mn, Co, Ni, Cu and Zn are coupled to synthesize MOF derivatives for energy storage. Metal species-dependent compositions including hydroxides, oxides, and hydroxide nitrates are observed. The nickel-based derivative (Ni-HBF) shows the highest specific capacitance (C F) of 698.0F/g at 20 mV/s, due to multiple redox states and advanced flower-like surface properties. The diffusion and capacitive-control contributions of MOF derivatives are also analyzed. The battery supercapacitor hybrid with Ni-HBF electrode shows a maximum energy density of 27.9 Wh/kg at 325 W/kg. The C F retention of 170.9% and Coulombic efficiency of 93.2% are achieved after 10,000 cycles. [ABSTRACT FROM AUTHOR]

The structure of the title salt, C4H7N2+·C9H5O6− (1), is reported. The compound is built from a protonated 2-methylimidazole and a singly deprotonated trimesic acid. Detailed analysis of bond distances and angles for both ions reveals subtle differences compared with their neutral molecule counterpart. Analysis of the crystal packing in compound 1 reveals the formation of undulating chains by the ions through hydrogen bonding. The chains stack along the b axis through π–π interactions and interconnect with other chains in an out-of-phase arrangement along the ac plane through further hydrogen-bonding interactions.

The structure of the title salt, C4H7N2+⋅C9H5O6- (1), is reported. The compound is built from a protonated 2-methylimidazole and a singly deprotonated trimesic acid. Detailed analysis of bond distances and angles for both ions reveals subtle differences compared with their neutral molecule counterpart. Analysis of the crystal packing in compound 1 reveals the formation of undulating chains by the ions through hydrogen bonding. The chains stack along the b axis through π--π interactions and interconnect with other chains in an out-of-phase arrangement along the ac plane through further hydrogen-bonding interactions. [ABSTRACT FROM AUTHOR]

The study reports the density (ρ), molar volume (V), partial molar volume (Vm1)/(Vm2) and refractive index (nD) of the binary mixture of 2‐methylimidazole and 1‐butanol/octanol at T=300.15–318.15 K. The accuracy of the experimental results was checked with different refractive mixing models like Lorentz‐Lorentz (L−L), Arago‐Biot (A−B), Gladstone‐Dale (G−D), Newton (N), Heller (H) and Wiener (W) and the root mean square deviation have also been presented.. The excess values were fitted to Redlich‐Kister polynomial equation and the standard deviations were also calculated. The negative VE and ΔnD values at higher mole fraction of 2‐methylimidazole indicate specific interaction between the unlike components due to hydrogen bonding but with rise in temperature the bonds tend to dissociate leading to restricted associations. Density functional theory has also been used to investigate the effective reactivity between 2‐methylimidazole and 1‐butanol/1‐octanol. The difference between ELUMO and EHOMO ranged from −12.9 to 16.523 kcal/mol. 2‐methylimidazole‐1‐octanol displayed greatest reactivity with lowest band energy gap. [ABSTRACT FROM AUTHOR]

The study aimed to compare zebrafish embryo mortality rates under different 2-Methylimidazole (2-MI) and 4-Methylimidazole (4-MI) concentrations. Two exposure groups were created at a 40μM concentration using egg water. Thirty individuals were divided into two groups: Group 1 received an environmentally relevant dose of 2-MI, while Group 2 was exposed to 4-MI. Each group’s embryos (n=15 per plate) were observed from 4 to 96 hours post fertilization (hpf), adhering to OECD guidelines. Statistical analysis using SPSS maintained a 95% confidence level, 0.01 ratio, 80% power, and 1:1 enrollment ratio. Results showed a marked increase in mortality rate (71.87±1.25) in ecologically exposed embryos compared to 2-MI (45.73±0.79), with a significant P-value of 0.000 (P

The title compound, (C4H7N2)2[Co(H2O)6][Co(C9H3O6)2(H2O)4] (1), was synthesized from cobalt(II) chloride, 1,3,5-benzene tricarboxylic acid (Hbtc) and 2-methyl-imidazole (H-2mIm) under ambient conditions. The structure of 1 is here reported and compared with the parent complex hexaaquacobalt bis(1H-imidazol-3-ium) tetraaquabis(benzene-1,3,5-tricarboxylato)cobalt (2).

[Display omitted] • A novel mixed imidazole ligand MIL-88A was proposed and prepared for the first time. • The photocatalyst revealed significantly smaller particle size and greatly improved photocatalytic capacity. • 100% decomposition of 100 ppm AR1 dye was achieved within 45 min of irradiation with the assistance of a trace amount of H 2 O 2. • A dye removal rate of 99.98% was maintained after five cycles. • Photo-generated h+ was the main oxidizing specie in the photocatalytic reaction. In this study, we fabricated MIL-88A metal–organic frameworks with excellent physicochemical properties using mixed organic ligands. In addition, we investigated the effects of different iron precursors on the physicochemical properties of the as-prepared MIL-88A samples. We determined that the difference between the dissociation rates of the metal ions of different iron precursors affected the crystallization rate of MIL-88A, which effectively decreased particle size, causing an increase in the adsorption capacity of MIL-88A and significantly improving its photocatalytic activity. Two organic ligands: 2-methylimidazole and fumaric acid, were mixed, and the formed dihydrate affected the crystallization rate of MIL-88A; moreover, the as-fabricated MIL-88A presented small particle size and high oxidation potential. The as-prepared mixed organic ligand MIL-88A removed 96.42% of AR1 dye from an AR1 dye solution with a concentration of 20 mg/L after 2 h of irradiation. Furthermore, an AR1 dye removal of 100% was achieved after only 45 min of irradiation using a 100 mg/L AR1 dye solution in the presence of trace H 2 O 2. The decomposition efficiency of MIL-88A did not decrease after five removal cycles, and this was attributed to the excellent decomposition efficiency of MIL-88A with mixed organic ligands, which was ascribed to its remarkable adsorption capacity and high oxidation potential. Strong oxidizing hydroxyl radicals were generated via a photo-Fenton reaction to improve the oxidative power of MIL-88A, and pollutants were decomposed without generating residues. We believe that these findings can be used to significantly expand the application of MIL-88A in photocatalysis research. [ABSTRACT FROM AUTHOR]

Novel zinc(II) coordination compounds with imidazole (Im) and 2-methylimidazole (2-MeIm) were prepared and characterized: [ZnX2(Im)2] (X = Cl (1a), Br (1b), I (1c)) and [ZnX2(2-MeIm)2] (X = Cl (2a), Br (2b), I (2c)). Coordination compounds 1a–c were prepared mechanochemically by neat grinding while 2a–c were prepared by solution synthesis. The complexes were characterized by FT-IR and NMR spectroscopy and by powder X-ray diffraction. Crystal and molecular structures were determined by the single crystal X-ray diffraction. The characteristic of all structures is a distorted tetrahedral coordination of zinc consisting of two halide atoms and two nitrogen atoms from the imidazole (or 2-methylimidazole) ligand. Molecules in 1a–c are interconnected by hydrogen bonds into 3D structures. Structures of 1b and 1c were found to have similar unit cells and similar crystal packing and hydrogen bonding. Introduction of the 2-methylimidazole substituent introduced disorder in the crystal structures of 2a–c. Because of the very small size of the crystals data were collected by synchrotron radiation. For the disordered 2a, 2b and 2c fixed geometry was used in refining of the structures. Crystal structures of 2a–c are characterized by chains of molecules connected by hydrogen bonds of the type N–H⋅⋅⋅X, with weak π⋅⋅⋅π and van der Waals interactions between the chains. The QTAIM, RDG and NCI computational analysis of 1a and 2a–c confirmed the presence of weak attractive intermolecular interactions that can be attributed to weak N–H⋅⋅⋅X and van der Waals interactions.

Keggin-type phosphotungstic acid (HPW) supported on imidazolyl-activated carbon (AC-COIMI-HPW) catalysts was prepared, which was used to catalyze the oxidation of benzyl alcohol with aqueous H2O2. In the presence of AC-COIMI-HPW, the benzyl alcohol conversion of 90.2% with 91.8% selectivity of benzaldehyde was obtained at 90°C for 6 h in an acetonitrile aqueous solution. The catalyst exhibited an outstanding performance for the oxidation of various benzyl alcohols and aliphatic alcohols. In addition, the catalyst could be easily recovered and reused five times without significant deactivation. The characterization results showed that HPW was chemically bonded on the surface of the carbon material through an ionic bond. It is proposed that the combination of the imidazole cation with the HPW anion could not only tune the redox catalytic properties of the PW anion but also enhance the compatibility of the catalyst in the reaction medium, thereby improving the catalytic performance.

In this study, a series of Ni-based Zeolitic Imidazolate Framework (ZIF) is successfully co-precipitated at room temperature with different ratios of nickel (II) nitrate hexahydrate (Ni(NO3)2⋅6H2O) to 2-methylimidazole (mIM) at different ratios of 3:10, 1:1, and 10:3, denoted as Ni-ZIF-1, Ni-ZIF-2, and Ni-ZIF-3. The morphology, elemental, and structural investigation of Ni-ZIFs are carried out using field emission scanning electron microscopy (FESEM), energy-dispersive X-Ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD). The electrochemical performance reveals that the Ni-ZIF-3 successfully delivered the highest specific capacitance of 433 F g−1 at current density of 0.25 A g−1. It is important to note that when Ni-ZIF-3 is used in carbon asymmetric supercapacitor (ASC), the specific capacitance of 85 F g−1 is achieved at a current density of 0.25 A g−1, whilst maintaining outstanding cycling stability of 93% after 1500 cycles at reversible current density from 0.5 A g−1 until 1.0 A g−1. A little decay during the cycle test demonstrates that the device is capable of offering durable devices with low internal resistance. [ABSTRACT FROM AUTHOR]

Manipulating the crystallographic orientation of zinc deposition is recognized as an effective approach to address zinc dendrites and side reactions for aqueous zinc-ion batteries (ZIBs). We introduce 2-methylimidazole (Mlz) additive in zinc sulfate (ZSO) electrolyte to achieve vertical electrodeposition with preferential orientation of the (100) and (110) crystal planes. Significantly, the zinc anode exhibited long lifespan with 1500 h endurance at 1 mA cm -2 and an excellent 400 h capability at a depth of discharge (DOD) of 34% in Zn||Zn battery configurations, while in Zn||MnO 2 battery assemblies, a capacity retention of 68.8% over 800 cycles is attained. Theoretical calculation reveals that the strong interactions between Mlz and (002) plane impeding its growth, while Zn atoms exhibit lower migration energy barrier and superior mobility on (100) and (110) crystal planes guaranteed the heightened mobility of zinc atoms on the (100) and (110) crystal planes, thus ensuring their superior ZIB performance than that with only ZSO electrolyte, which offers a route for designing next-generation high energy density ZIB devices.

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Composition of biligand compounds Cu(C3H4N2, C4H6N2)x( )2· nH2O obtained by reaction of aqueous suspensions of prepared poorly soluble copper(II) benzoate Cu(C7H5O2)2 · 3H2O and nicotinate Cu(C6H4NO2)2 · H2O with imidazole and 2-methylimidazole has been determined. Mono- and biligand salts have been analyzed and their thermal decomposition has been studied. IR spectroscopy has shown the participation of pyridine nitrogen of imidazole and carboxylic groups of aromatic acids in binding to copper(II) ion. Composition and stability of copper(II) benzoate complex, solubility constant for salt Cu(C7H5O2)2 · 3H2O at ionic strength I = 0.1 have been determined by solubility method, pH potentiometry, and photometry. Co-crystals/salts of composition C3H4N2 · C7H6O2 (pH 8.0), C3H4N2 · C6H5NO2 (pH 7.4) and 3(C4H6N2) · C19H19O6N7 · 2H2O (pH ~7) have been prepared and studied by thermogravimetric analysis. X-ray powder diffractograms have been recorded for initial compounds and their reaction products (imidazole–benzoic acid, 2-methylimidazole–folic acid systems). [ABSTRACT FROM AUTHOR]

2-Methylimidazolium pyridine-2,5-dicarboxylato zinc(II) dihydrate crystal (1) is synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), single crystal X-ray diffraction analysis (SCXRD), thermogravimetric-differential thermal analysis (TG-DTA), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), powder X-ray diffraction analysis (PXRD), proton nuclear magnetic resonance (1H NMR) studies, electronic absorption studies (UV-VIS) and DNA interaction studies. 1 was then explored for anti-microbial, anti-oxidant and anti-cancer activity. The SCXRD studies show that the compound crystallizes in the triclinic system and exhibits a distorted octahedral geometry with methyl imidazole ion as the cation. An exothermic decomposition at 400 °C implies high temperature stability in TG-DTA. PXRD confirms the phase purity of the sample. 1H NMR and UV-VIS results show that the solution structure of 1 is in agreement with SCXRD data. DNA interactions evaluated by agarose gel electrophoresis method substantiate the intercalative mode of binding. Anti-oxidant analysis shows that it exhibits good scavenging ability against DPPH and NO radicals. Anti-microbial activity suggests that 1 has better activity against Escherichia coli than Staphylococcus aureus. Further, the potential anti-cancer activities of complex indicate that the compound has good activity with a half-maximal inhibition concentration (IC50) value of 21.3 against MCF-7 human breast cancer cell line, suggesting that it may act as an anti-breast cancer drug. [ABSTRACT FROM AUTHOR]

The complex formation of H[AuCl4] with 2-methylimidazole was studied by the potentiometric method at 288–318 K. It was found that even with excess 2-methylimidazole in the solution, three chloride ions of H[AuCl4] are replaced. The general stability constants of the resulting complexes were calculated over a broad temperature range (at 298 K: log β1 = 8.04 ± 0.04; log β2 = 13.53 ± 0.03; log β3 = 19.23 ± 0.09). With increasing temperature and ionic strength of the solution, the general stability constants increase. The thermodynamic constants of formation of the complexes were calculated. The difference between the concentration and thermodynamic constants depends on the value Δνz2 (Δνz2 = ). The formation of all complex species was accompanied by energy absorption. The ΔS value was positive for all complex formation steps. For the equilibrium [AuCl4]– + L ↔ [AuLCli]3 –i + (4 – i)Cl–, the numbers of moles of reactants and products remain invariable. The increase in entropy upon complexation is, most likely, due to appearance of water in the solution "unfrozen" from the hydration shells of ions as a result of the reactions. The ΔG value was negative for all complex formation steps. The spontaneous occurrence of the complex formation reaction is determined by the entropy component. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co(II), Cu(II), and Zn (II) complexes of mefenamic acid are synthesized • The complexes were structurally characterized using SCXRD • TG analysis determined their compositions and thermal stability • Cytotoxic activity evaluated by MTT assay on lung cancer cells (NCIH-460) and breast cells (MDAMB) Mefenamic acid (mef), a widely used nonsteroidal anti-inflammatory drug in pain treatment, was utilized as the starting material in synthesizing three metal (II) complexes in the presence of 2-methylimidazole (mei) co-ligand. The newly synthesized complexes, [Co(mef) 2 (mei) 2 (C 2 H 5 OH) 2 ]; (1) , [Cu(mef) 2 (mei) 2 (C 2 H 5 OH) 2 ]; (2) , and [Zn(mef) 2 (mei) 2 ]; (3) , were characterized using elemental analysis, spectroscopic techniques (FTIR, UV–Vis), thermal analysis, and single crystal X-ray crystallography. Complex (3) was further characterized by 1H and 13C NMR and PXRD. FTIR studies confirmed the coordination of mefenamato ligand and 2-methylimidazole in the complexes, while TG analysis determined their compositions and thermal stability. Complexes (1) and (2) were found to be isostructural, with an octahedral geometry and surrounded by monodentate ligands, while complex (3) is a tetrahedral Zn(II) complex. In addition, the MTT test was used to investigate the cytotoxicity of mefenamic acid and the complexes on lung cancer cells (NCIH-460), breast cells (MDAMB), and normal cells (L929). Complex (1) demonstrated the most significant anti-MDAMB cell line activity. [ABSTRACT FROM AUTHOR]

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This study mainly reports on the preparation of Sn-imidazolates (Sn(Im)n) supported on boron and nitrogen-doped activated carbon (AC), which proved to be highly active catalysts for the acetylene hydrochlorination. The obtained materials were characterized by FTIR spectroscopy, X-ray diffraction, N2 physisorption, scanning electron microscopy, thermogravimetry, temperature programed desorption, and X-ray photoelectron spectroscopy. The catalytic results revealed that the Sn(Im)n/AC materials manifest enhanced activity and long-term stability than SnCl2/AC catalyst. Regarding the lifetime, 10%Sn(Im)n/(10%BNAC-800) catalyst, exhibiting an acetylene conversion of 80% after 40 h of reaction, is more promising in comparison with 10%Sn(Im)n/AC. These results indicate that the use of 2-methylimidazole improve the activity and stability of SnCl2/AC catalysts in the hydrochlorination of acetylene. Particularly, the supports modified with boric acid and melamine can effectively increase the lifetime of Sn(Im)n/AC catalysts. [ABSTRACT FROM AUTHOR]

It is a highly desired yet challenging task to replace rare and expensive noble metal catalysts with inexpensive and earth-abundant metal ones in electrochemical sustainable chemistry field. Herein, the bimetallic zinc-cobalt layered double hydroxide nanosheets (ZnCo-LDH NS) have been facilely synthesized using 2-methylimidazole as a bifunctional alkali source (OH−) and a morphological controlling reagent by the one-step room-temperature reaction. The mechanism study shows that the weak organic base of 2-methylimidazole-induced slow release of OH− in water/ethanol is the controlling factor for the formation of the LDH nanosheets. The ZnCo-LDH NS modified on glassy carbon electrode exhibited an overpotential of 385 mV at 10 mA cm−2 and a Tafel slope of 108 mV dec−1 in 1.0 M KOH for oxygen evolution reaction, outperforming the corresponding the monometal oxides of Zn-OH, Co-OH, the NaOH produced ZnCo-LDH microparticles, and even the benchmark catalyst of RuO 2 at high current density. Characterization experiments indicated that the outstanding electrocatalytic activity can be ascribed to the nanosheet-induced surface area effect, excellent electronic conductivity, and the coupling effect between Zn2+ and Co2+ in the material. This work offers a facile and environmental-friendly method for synthesising LDH nanosheets bearing enhanced oxygen evolution reaction activity. [ABSTRACT FROM AUTHOR]

In situ formation of 2-methylimidazole as a result of 2,4,6-trimethyl-1,3,5-hexahydrotriazine trihydrate and glyoxal interaction in an aqueous solution is studied for the first time using NMR spectroscopy. In addition to the reactants and products, the reaction mixture is shown to contain stable intermediate products of the trimer decomposition as well as glycolic acid. [ABSTRACT FROM AUTHOR]

Two new metal–organic frameworks (MOFs), namely, three‐dimensional poly[diaquabis{μ2‐1,4‐bis[(2‐methyl‐1H‐imidazol‐1‐yl)methyl]benzene}bis(μ2‐glutarato)dinickel(II)] monohydrate], {[Ni2(C5H6O4)2(C16H18N4)2(H2O)2]·H2O}n or {[Ni2(Glu)2(1,4‐mbix)2(H2O)2]·H2O}n, (I), and two‐dimensional poly[[{μ2‐1,4‐bis[(2‐methyl‐1H‐imidazol‐1‐yl)methyl]benzene}(μ2‐glutarato)zinc(II)] tetrahydrate], {[Zn(C5H6O4)(C16H18N4)]·4H2O}n or {[Zn(Glu)(1,4‐mbix)]·4H2O}n (II), have been synthesized hydrothermally using glutarate (Glu2−) mixed with 1,4‐bis[(2‐methyl‐1H‐imidazol‐1‐yl)methyl]benzene (1,4‐mbix), and characterized by single‐crystal X‐ray diffraction, IR and UV–Vis spectroscopy, powder X‐ray diffraction, and thermogravimetric and photoluminescence analyses. NiII MOF (I) shows a 4‐connected 3D framework with point symbol 66, but is not a typical dia network. ZnII MOF (II) displays a two‐dimensional 44‐sql network with one‐dimensional water chains penetrating the grids along the c direction. The solid‐state photoluminescence analysis of (II) was performed at room temperature and the MOF exhibits highly selective sensing toward Fe3+ and Cr2O72− ions in aqueous solution. [ABSTRACT FROM AUTHOR]

The catalytic effects of 1,5,7‐Triazabicyclo[4.4.0]dec‐5‐ene (TBD) with 2‐methylimidazole‐intercalated α‐zirconium phosphate (α‐ZrP∙2MIm) in the reaction of glycidyl phenyl ether (GPE) and hexahydro‐4‐methylphthalic anhydride (MHHPA) were investigated. The reaction did not proceed within 1 h at 60 °C. On increasing the temperature to 100 °C, the conversion reached 93% for 1 h. Without the addition of TBD, the conversion was 67% at 100 °C for 1 h. Under storage conditions at 25 °C for 7 days, the conversion of GPE was only 18%. The curing behavior of 2,2‐bis(4‐glycidyloxyphenyl)propane (DGEBA) and MHHPA in the presence of TBD with α‐ZrP∙2MIm was evaluated by differential scanning calorimetry. The addition of TBD with α‐ZrP∙2MIm as a latent thermal initiator, the storage stability was maintained and the reaction proceeded rapidly under heating conditions. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2557–2561 [ABSTRACT FROM AUTHOR]

The present research assessed, for the first time, toxicity of ZIF-8 (1 mg/L) and the building blocks (0.1 mg/L Zn2+ and 0.4 mg/L 2-methylimidazole (2-MIm)), besides that of AgNPs@ZIF-8 (0.25, 0.5, and 1 mg/L) and AgNO 3 (0.1 mg/L) to aquatic organisms. Two consecutive generations (F0 & F1) of Artemia salina were exposed to these chemicals. All of the chemical treatments considerably caused mortality in F0, especially AgNPs@ZIF-8 and AgNO 3 , whereas F1 displayed notable tolerance and survived comparable to the control group, except in the case of AgNO 3 treatment. Similarly, growth indices (weight, mainly in ZIF-8, Zn2+, and 2-MIm; length, in Ag-doped ZIF-8 and AgNO 3) were significantly retarded in F0 and especially F1 of all treatments, and 2-MIm caused the greatest length retardation in F0. AgNPs@ZIF-8 (0.5 and 1 mg/L), 2-MIm, and AgNO 3 postponed the ovary emergence in about 40%–60% of the exposed F0, and ZIF-8 delayed this phenomenon in some individuals of F0 and F1 up to 6 days. This temporal disturbance was also observed in time to first brood of almost all experimental F0 and F1 groups, with being over 80% of F1 exposed to ZIF-8, 2-MIm, and Zn2+, as well as about 50% of F0 treated with 2-MIm, and Zn2+. The highest neonate number was recorded for F0 and F1 exposed to AgNO 3 and Zn2+, while ZIF-8 and, importantly, 2-MIm decreased the reproductivity to the lowest levels in both generations. Generally, the reproductive frequency was significantly decreased in all F0 and F1 treatments, especially 2-MIm, ZIF-8, AgNPs@ZIF-8 (0.25 & 1 mg/L). This study highlighted the neglected importance of 2-MIm in assessing overall toxicity of ZIF-8, and even other organic ligands of MOFs, and also filled a gap in the literature by investigating the potential effect of additives such as AgNPs on the toxicity of ZIF-8 and other MOFs. [Display omitted] • Addition of metal nanoparticles increased toxicity of ZIF-8 nanoparticles. • ZIF-8, AgNPs@ZIF-8 and their constituents reduced growth performance in Artemia. • ZIF-8, 2-MIm, and AgNPs@ZIF-8 postponed maturity in F0 Artemia , up to 6 days. • ZIF-8, 2-MIm, and Zn2+ delayed breeding time for >80% of F1 Artemia. • 2-MIm caused high reproductive toxicity to F0 and F1 Artemia. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D porous MXene microgels were induced by 2-MeIM. • The intercalated 2-MeIM can improve the layer spacing of MXene nanoshets. • M-MXene film exhibits a high capacitance of 223.4 F g−1 at 1000 mV s−1. • MXene//AC supercapacitor displays a 16.88 Wh kg−1 at 799 W kg−1. Ti 3 C 2 T x MXene has been considered a potential supercapacitor electrode material on account of its fast electron transfer performance, large volume pseudocapacitance, excellent hydrophilicity and mechanical properties. However, the serious stacking of MXene nanosheets reduced the exposed active sites and hindered diffusion of ions, leading to bad electrochemical property. Here, we report a strategy to transform MXene nanosheets into 3D MXene microgels induced by 2-methylimidazole. Benefitting from the existence of microgels, it facilitates the rapid vacuum filtration to prepare the porous MXene film, thus enhancing the ion transfer efficiency. Furthermore, 2-methylimidazole can also act as an intercalated agent to increase the layer spacing of MXene nanosheets. Therefore, the as-prepared porous MXene film demonstrates a superior rate capacity, and its capacitance reaches 223.4 F g−1 at the scan rates of 1000 mV s−1. Moreover, the assembled MXene//AC asymmetrical supercapacitor displays a 16.88 Wh kg−1 at a power density of 799 W kg−1, and maintains 13.11 Wh kg−1 at a power density of 8 kW kg−1. This work develops a simple way to prepare the porous MXene film for supercapacitors with excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Ab initio calculations were carried out to study the geometry, solvation free energy, dipole moment, molecular electrostatic potential (MESP), Mulliken and Natural charge distribution, polarizability, hyperpolarizability, Natural Bond Orbital (NBO) energetic and different molecular properties like global reactivity descriptors (chemical hardness, softness, chemical potential, electronegativity, electrophilicity index) of 2-methylimidazole. B3LYP/6-31G(d,p) level of theory was used to optimize the structure both in the gas phase and in solution. The solvation free energy, dipole moment and molecular properties were calculated by applying the Solvation Model on Density (SMD) in four solvent systems, namely water, dimethylsulfoxide (DMSO), n-octanol and chloroform. The computed bond distances, bond angles and dihedral angles of 2-methylimidazole agreed reasonably well with the experimental data except for C(2)-N(1), C(4)-C(5) and N(1)-H(7) bond lengths and N(1)-C(5)-C(4) bond angle. The solvation free energy, dipole moment, polarizability, first order hyperpolarizability, chemical potential, electronegativity and electrophilicity index of 2-methylimidazole increased on going from non-polar to polar solvents. Chemical hardness also increased with increasing polarity of the solvent and the opposite relation was found in the case of softness. These results provide better understanding of the stability and reactivity of 2-methylimidazole in different solvent systems.

A novel polyoxometalate-based coordination supramolecule was synthesized via a hydrothermal method. The compound exhibited high proton conductivity with good stability. Polyoxometalate skeleton, 2-methylimidazole ligands and water molecules provided continuous hydrogen bonds for the proton conduction. Kinetic studies indicated that the proton conduction mechanism of the compound followed the vehicle mechanism. Developing new low-cost and efficient proton-conducting materials remains an attractive and challenging task. Herein, a Preyssler-type polyoxometalate derived coordination compound had been synthesized with a hydrothermal method, namely, H 4.5 NaCo 5 (2-MI) 15.5 (2-MI) 3 [NaP 5 W 30 O 110 ]·5H 2 O (1) (where 2-methylimidazole is abbreviated as 2-MI, and partial 2-MI was deprotonated). The structure was characterized by single crystal X-ray diffraction, PXRD, FT-IR, TG, CHN and ICP-OES elemental analyses. We studied the relationship between the crystal structure and proton conduction of compound 1 and found that the presence of 2-MI reduced the leakage of polyoxometalate under high relative humidity. Meanwhile, the strong interaction of the counter cation Na+ with water is beneficial to form more hydrogen bonds. Compound 1 showed the maximum proton conductivity with a value of 4.42 × 10−3 S cm−1 at 367 K and 97% RH. Kinetic investigation indicates that the proton conduction mechanism of compound 1 follows the vehicle mechanism. [ABSTRACT FROM AUTHOR]

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Carboxylate-based metal–organic frameworks (CMOFs) have received considerable attentions for their high stability, catalytic activity, and porosity. However, synthesis of CMOFs requires high temperature, pressure, and long reaction time. Here, we explored the activity of 2-methylimidazole (2-MIM) for ultrafast synthesis of CMOF nanostructures (CMOFNs), in aqueous medium at room temperature and reaction time of 10 min. Seven CMOFNs have been synthesized by using Al3+, Cr3+, Cu2+, Fe3+, In3+, or Cd2+ salt and 1,4-bezenedicarboxylic acid, or 1,3,5-benzenetricarboxylic acid. Through this technique, the CMOFs with space time yield 181–501 kg m−3 day−1 and crystal sizes of ca. 200–700 nm was obtained. [ABSTRACT FROM AUTHOR]

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[Display omitted] • New ligand (MeIm-Cp) and coordination polymerrs namely {[Ag 3 (MeIm-Cp) 2 ](NO 3) 3 } n (1) and {[Ag(MeIm-Cp)](CH 3 PhSO 3)} (2), were synthesized. • The structure was determined single crystal X-ray diffraction technique. • Thermal stabilities were investigated. • Dye adsorption behaviour of the cyclotriphosphazene based coordination polymer against methyl orange, tartrazine and methylene blue were investigated in this study. Coordination polymers are a promising crystalline framework for dye capture and separation in recent years. We are reporting herein the two new, Ag(I) coordination polymers, namely {[Ag 3 (MeIm-Cp) 2 ](NO 3) 3 } n (1) and {[Ag(MeIm-Cp)](CH 3 PhSO 3)} (2), were synthesized from hexapodal-shaped 2-methylimidazole substituted cyclotriphosphazene, (MeIm-Cp). MeIm-Cp was characterised by 1H NMR, 31P NMR and mass analysis. Structure of each isolated compounds were assigned by single crystal X-ray crystallography. In complex 1 , MeIm-Cp has a κ6N coordination mode by connecting six Ag(I) ions to constitute a 3D coordination framework whereas the ligand in complex 2 displays κ4N coordination mode via linking four Ag(I) ions together to create a 2D coordination polymer. Topologically, coordination polymer 1 exhibits a 4,4,6-connected three nodal net with point symbol {44.62} 3 {46.68.8} 2 , while coordination polymer 2 displays a four-connected network having the point symbol {43.63}. According to thermogravimetric analysis, the thermal stability of MeIm-Cp is higher than complexes. The synthesized coordination polymers were used for the adsorption of some cationic and anionic organic dyes in aqueous media, Dye adsorption studies were performed out using UV–Vis. absorption spectroscopy. Adsorption experiments show that complex 1 removes the anionic methyl orange (MO) and tartrazine (E102) from water but shows no adsorption behaviour toward the cationic methylene blue (MB). [ABSTRACT FROM AUTHOR]

Magnetic metal absorbers are susceptible to strong corrosion in acid, alkali and salt fog environments, resulting in strong limitations of their applications. Therefore, it is urgent to develop magnetic absorber with enhanced anti-corrosion and microwave absorption. In this paper, carbonyl iron powder (CIP) coated with 2-methylimidazole/epoxy (2-MI/EP) composites were prepared by in-situ polymerization. The CIP@2-MI/EP composites showed better microwave absorption performance with a minimum reflection loss (RL min) value of −54.11 dB at 9.69 GHz with 2 mm thickness. The electrochemical test results show that the corrosion current density of the composites decreases by two orders of magnitude and the corrosion potential is positively shifted to −0.1. In addition, the presence of 2-MI/EP layer can enhance the oxidation resistance of this composite. Considering the corrosion resistance, electromagnetic properties and oxidation resistance of this composite material, it provides an opportunity for valuable addition at commercial level. [Display omitted] • The CIP@2-MI/EP composite absorbing material with excellent corrosion resistance was prepared by in-situ polymerization. • The electrochemical test show that the corrosion current of CIP@2-MI/EP is two orders of magnitude lower than that of CIP. • The CIP@2-MI/EP composites showed better microwave absorption performance. [ABSTRACT FROM AUTHOR]

In the title compound, [Fe(C48H36N4)(C4H6N2)2]ClO4·1.5C4H8O, the iron(III) metal is coordinated in a distorted octahedral geometry by four pyrrole N atoms of the porphyrin ligand in the equatorial plane and two N atoms of 2-methylimidazole ligands in the axial sites. The complex has a highly ruffled porphyrin core with mean absolute core-atom displacements Ca, Cb, Cm and Cav of 0.25 (5), 0.17 (12), 0.432 (16) and 0.25 (13) Å, respectively. One of the four phenyl groups of the porphyrin is disordered over two sets of sites with refined occupancy ratio of 0.718 (7):0.282 (7). The mean Fe—Np (Np is a porphyrin N atom) bond length [1.975 (9) Å] indicates the low-spin state of the iron atom. The two 2-methylimidazole ligands are nearly perpendicular and form a dihedral angle of 86.93 (10)°. The dihedral angles between the 2-methylimidazole ligands and the closest Fe—Np vector are 38.04 (9) and 35.00 (7)°. In the crystal, the complex cations interact with the perchlorate anions through N—H...O hydrogen bonds, forming chains running parallel to [110].

The mixed-ligand copper(II) iminodiacetates [Cu(ida)(2-mim)(H2O)2]·H2O (1), [Cu(ida)(2-mim)2]·2H2O (2), [Cu(ida)(2-mim)(H2O)]n·4.5nH2O (3), and [Cu2(ida)2(2-mim)2]n·nH2O (4) (H2ida = iminodiacetic acid, 2-mim = 2-methylimidazole) were obtained from neutral or alkaline solutions at different temperatures. The novel complex 4 contains very small holes with diameters of 2.9 Å, which can adsorb O2 selectively and reversibly between 1.89 to 29.90 bars, compared with the different gases of N2, H2, CO2, and CH4. This complex is stable up to 150 °C based on thermal analyses and XRD patterns. The four complexes show catalytic activities that facilitate the conversion of cyclohexane to cyclohexanol and cyclohexanone with hydrogen peroxide in a solution. The total conversion is 31% for 4.

Abstract: Activated carbon was modified by loading 2‐methylimidazole (mIm), ethanol, and glycol onto its surface and adopted to capture CO2 using the absorption‐adsorption method. The modified activated carbon showed high selectivity for separating CH4+CO2 gas mixtures, compared with other methods to modify activated carbon given in the literature. The separation factor was 4.75 times higher than that for the fresh activated‐carbon system, and the separation performance of the activated carbon increased with increasing amount of mIm. The addition of glycol showed greater potential to enhance the selectivity of the activated carbon than ethanol. A recycling test verified the stability of the modified activated carbon for CH4+CO2 gas mixture separation. [ABSTRACT FROM AUTHOR]

A novel polyoxometalate-based organic–inorganic hybrid compound, (C 4 H 7 N 2 ) 2 (H 3 O) 2 [β-Mo 8 O 26 ]·2H 2 O (1), has been synthesized and structurally characterized by single-crystal X-ray diffraction methods, IR spectroscopy, UV–Vis absorption. Compound (1) crystallizes in the Triclinic system, space group P -1 with unit a = 8.379 (3) Å, b = 10.200 (5) Å, c = 10.861 (5) Å, α = 68.27° (3), β = 71.61° (2), γ = 78.40° (3), V = 814.5 (6) Å 3 , Z = 2. The refinement of the structure leads to a residual factor R = 0,050 for 3549 independent observed reflections [I > 2σ(I)] and 227 parameters. The structure of (1) consists of [β-Mo 8 O 26 ] 4- anions with [C 4 H 7 N 2 ] + , H 3 O + cations and water molecules connected to the mineral parts by hydrogen bonds. Furthermore, we report results of the thermogravimetric analysis, cyclic voltammetry measurement and Hirshfeld surface studies. [ABSTRACT FROM AUTHOR]

Caramel colours are used by the food industry in a wide range of foods and beverages. During their manufacturing, low molecular weight compounds such as 4-methylimidazole (4-MEI), the structural isomer of 4-MEI, 2-methylimidazole (2-MEI) and 2-acetyl-4-tetrahydroxy-butylimidazole (THI) are generated. The presence of these inevitable by-products of caramel manufacturing can be hazardous to human health. This publication describes an isotope dilution Ultra-High-performance Liquid Chromatography tandem mass spectrometric method (UHPLC-MS/MS) that was developed and validated for the simultaneous quantification of these impurities in both beverages/liquids and foods. A limit of quantification of 5 μg/kg was obtained for 4-MEI and THI. The expanded measurement uncertainty (U; k  = 2) for these compounds was below 51% in beverages/liquids and below 56% in foods. As higher measurement uncertainties were obtained for 2-MEI, the developed analytical procedure can only be used in a semi-quantitative way for this compound. [ABSTRACT FROM AUTHOR]

The microwave-assisted syntheses of anion exchange resins were carried out in the presence of selected organic solvents and amines, applying variable radiation density. The polymers were used for sorption of ReO4-, after which, the collected results were set together with the applied synthesis parameters. The greatest Re(VII) sorption capacity of 470 mg Re g−1 was revealed by a resin obtained within 10 min in the presence of N,N-dimethylformamide and 2-methylimidazole at power of 160 W. The outcome of the present research constitutes a set of guides allowing to enhance the resource-efficiency of the process. [ABSTRACT FROM AUTHOR]

In this study, the stability of zeolitic imidazolate framework-8 (ZIF-8) was investigated in 7 common anions aqueous solutions. Experimental results showed that Cl − , SO 4 2− , NO 3 − , PO 4 3− , and CO 3 2− have insignificant change in the crystallinity and permanent porosity of ZIF-8 by SEM, XRD, nitrogen sorption and dissolution of Zn and 2-methylimidazole (Hmim) characterizations. Nevertheless, ZIF-8 crystalline phase and its porous character are transformed by the presence of HCO 3 − and HPO 4 2− .The dissolution of Zn and Hmim underwent a process of a giant ascent at the first stage and a following drop until a steady state in the two mediums. On the other hand, the morphology of ZIF-8 and the XRD peaks changes apparently in the both solutions. However, ZIF-8 possesses a higher stability when Hmim is introduced in the solution due to the inhibiting re-dissolution of ZIF-8 in the two solutions. [ABSTRACT FROM AUTHOR]