The synthesis of ionic liquids (ILs) usually involves two steps: (i) quaternization of a precursor followed by (ii) a salt metathesis reaction to introduce the desired anion. A consequence of the second step is that most ILs still contain some amount of the initial anion, often chloride. In this work, wavelength dispersive X-ray fluorescence (WDXRF) spectrometry is presented for the direct measurement of chlorides in ILs. The WDXRF settings were optimized, and the system was calibrated for the detection of chloride in several analogues of the commercially available IL Aliquat 336, [A336][X] (with X = I-, Br-, NO3 -, or SCN-). The Cl Kα intensity showed excellent linearity for samples with a conversion >0.80 (approximately Cl < 8000 ppm). Synthetic quality control samples showed that the instrumental error and deviations induced by the calibration procedure were small with maximum values of 1 and 5%, respectively. Detection and quantification limits depended strongly on the matrix (i.e., anion system and dilution) but were relatively low: 42-191 and 127-578 ppm Cl, respectively. Compared with other analytical techniques used for this purpose, the strengths of WDXRF include its ease of use, rapid measurements, the near absence of sample preparation steps, and versatility in terms of anion systems and chloride concentration range.

The present work explores the structural, microstructural, optical, magnetic, and hyperfine properties of Co0.3Zn0.7Fe2O4 microspheres, which have been synthesized by a novel template-free solvothermal method. Powder X-ray diffraction, electron microscopic, and Fourier transform infrared spectroscopic techniques were employed to thoroughly investigate the structural and microstructural properties of Co0.3Zn0.7Fe2O4 microspheres. The results revealed that the microspheres (average diameter ∼121 nm) have been formed by self-assembly of nanoparticles with an average particle size of ∼12 nm. UV-vis diffuse reflectance spectroscopic and photoluminescence studies have been performed to study the optical properties of the sample. The studies indicate that Co0.3Zn0.7Fe2O4 microspheres exhibit a lower band gap value and enhanced PL intensity compared to their nanoparticle counterpart. The outcomes of dc magnetic measurement and Mössbauer spectroscopic study confirm that the sample is ferrimagnetic in nature. The values of saturation magnetization are 76 and 116 emu g-1 at 300 and 5 K, respectively, which are substantially larger than its nanosized counterpart. The infield Mössbauer spectroscopic study and Rietveld analysis of the PXRD pattern reveal that Fe3+ ions have migrated from [B] to (A) sites resulting in the cation distribution: (Zn2+ 0.46Fe3+ 0.54)A[Zn2+ 0.24Co2+ 0.3Fe3+ 1.46]BO4. Comparison of electrochemical performance of the Co0.3Zn0.7Fe2O4 microspheres to that of the Co0.3Zn0.7Fe2O4 nanoparticles reveals that the former displays greater specific capacitance (149.13 F g-1) than the latter (80.06 F g-1) due to its self-assembled porous structure. Moreover, it was found that Co0.3Zn0.7Fe2O4 microspheres possess a better electrochemical response toward H2O2 sensing than Co0.3Zn0.7Fe2O4 nanoparticles in a wide linear range.

The use of liquid sulfur dioxide as a reaction solvent to promote chemical transformations of alkynes has been explored. First, a combination of liquid SO2 and In(OTf)3 or Hf(OTf)4 as a catalyst allows to perform hydration of aryl alkynes under mild conditions without a direct addition of Brønsted acid. Second, novel catalyst-free conditions for the synthesis of α-vinyl iodides, bromides, and chlorides from aryl alkynes have been developed in liquid SO2 using group I and II metal halides and ammonium iodide as the halide ion sources.

Series of sulfonamide-substituted amide (9-11), benzamide (12-15), and 1,3-disubstituted thiourea (17-26) derivatives were synthesized from a common precursor, i.e., substituted benzoyl chlorides. Structures of all of the synthesized compounds were characterized by spectroscopic techniques (1H nuclear magnetic resonance (NMR),13C NMR, and Fourier transform infrared spectroscopy (FTIR)). All of the amide (9-15) and thiourea (17-26) derivatives were screened against human carbonic anhydrases, hCA-II, hCA IX, and hCA-XII. Sulfonamide-substituted amides 9, 11, and 12 were found to be excellent selective inhibitors with IC50 values of 0.18 ± 0.05, 0.17 ± 0.05, and 0.58 ± 0.05 μM against hCA II, hCA IX, and hCA XII, respectively. Compound 9 was found to be highly selective for hCA II and about 6-fold more potent as compared to the standard antagonist, acetazolamide. Safe toxicity profiling of the most potent and selective compounds was determined against normal BHK-21 and HEK-293 T cells. Molecular docking studies were performed, which described the type of interactions between the synthesized compounds and enzyme proteins. In addition, in silico absorption, distribution, metabolism, and excretion (ADME) studies were performed, which showed that all of the synthesized molecules fulfilled the druggability criteria.

The hypercoordinated silicon chlorides ClSi[(o-OC6H4)3N] (3) and ClSi[(OC6H2Me2CH2)3N] (5) were used for the synthesis of catenated derivatives (Me3Si)3SiSi[(o-OC6H4)3N] (9), (Me3Si)3SiSiMe2SiMe2Si(SiMe3)2Si[(o-OC6H4)3N] (11), and (Me3Si)3SiSi[(OC6H2Me2CH2)3N] (13) in reactions with (Me3Si)3SiK·THF (7) or (Me3Si)3SiK·[18-crown-6] (8). It was found that the nature of the (Me3Si)3SiK solvate determines the product of interaction, resulting in the formation of (Me3Si)3Si(CH2)4OSi[(OC6H2Me2CH2)3N] (12) or 13. Compounds obtained were characterized using multinuclear NMR and UV-vis spectroscopy and mass spectrometry. The molecular structures of 3, 9, and 11-13 were investigated by single-crystal X-ray analysis, featuring hypercoordinated Si atoms in a trigonal-bipyramidal coordination environment with O atoms in the equatorial plane. The structure of the side product [N(CH2C6H2Me2O)3Si]2O (6) was also studied, indicating highly tetrahedrally distorted trigonal-bipyramidal environment at the Si atoms, which was confirmed by crystal density functional theory calculations indicating the very weak Si ← N interaction. The Si···N interatomic distances span a broad range (2.23-2.78 Å). The dependence of structural and NMR parameters for hypercoordinated catenated compounds from the type of the ligand was established.

The fouling of AISI 316L stainless steel during themanufacture of polymeric methylene diphenyl diisocyanate (pMDI) has been investigated. Studies have been carried out using a laboratory-based rig that simulates the process chemistry of the production plant. A variety of solution concentrations and treatment times have been employed to represent different stages in the production process. Following exposure, steel coupons have been removed and studied by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The thickness of the fouling layer, determined by XPS, is found to vary inversely with exposure time and solution concentration. This is a result of the solubility of the different pMDI derivatives that have been formed at different stages, and a reaction scheme is developed to explain these inverse relationships. ToF-SIMS indicates the formation of metal chlorides as a result of the initial treatment of the steel in the reaction vessel with hydrogen chloride. Fragment ions characteristic of reacted and unreacted pMDI (at m/z = 106 and 132 au, respectively) were used as an indicator of the degree of reacted isocyanate groups within the fouling layer and show a decrease with increasing exposure time, as a result of the formation of intermediates such as amines, ureas, carbodiimides, and uretonimines. The ToF-SIMS data was also processed by principal component analysis (PCA). This generally reinforced the conclusions reached by XPS and ToF-SIMS but, in addition, gave confidence in the repeatability of the analyses with the repeat data (of four analyses) clustering very tightly in the PCA score plots.

Chemical looping combustion (CLC) is one of the most promising methods for carbon capture and storage (CCS). An oxygen carrier, i.e., a mineral that can be oxidized and reduced, is used to convert the fuel in the process. The produced CO2 is inherently separated from the air components that enables easier CCS. The use of biomass-based fuels is desirable since it can lead to negative CO2 emissions. On the other hand, alkali compounds from the biomass may interact with the oxygen carrier causing problems, such as deactivation of the oxygen carrier. The most common oxygen carriers contain iron, since iron-based ores and industrial waste materials are readily available and cost-efficient. Therefore, the interaction between the iron oxygen carriers and the biomass ash-forming compounds needs to be investigated. Since Ca/Mg are abundant in biomass, it is important to clarify how their compounds interact with the oxygen carrier. In this study, the effect of Ca/Mg carbonates, chlorides, nitrates, sulfates, and phosphates along with synthetic biomass-derived ash on iron oxides was investigated. Redox reactions were investigated at 950 °C during 5 h under both oxidizing and reducing atmospheres. The results showed that the effect of Ca/Mg salts on the oxygen carrier varied depending on the anion of the salt. Generally, the nitrate- and phosphate-based salts of both Ca and Mg showed the harshest effect regarding agglomeration of the oxygen carriers. It was shown that the Ca/Mg-based compounds interacted differently with iron oxides, which was an unexpected result.

Two zinc (Zn) complexes, [Zn2(DAT)2Cl4] (I) and [Zn2(DAT)2(NO3)4] (II), were prepared by grinding 3,5-diamino-1,2,4-triazole (C2H5N5, DAT) with Zn precursors such as ZnCl2 and Zn(NO3)2, respectively. This solid-state reaction gives the corresponding Zn complex as the sole product in over 99% yield. This mechanochemical method promotes the selective formation of Zn complexes different from those obtained using the conventional solution-based route. The crystal structures of the two complexes were analyzed by single-crystal X-ray diffraction. Complex (I) crystallizes in the monoclinic space group P21/c, whereas complex (II) crystallizes in the triclinic space group P 1̅. Each complex is characterized by the presence of a characteristic DAT-bridged dimer with one DAT ligand per Zn atom, and the DAT ligand provides a bridge between the two Zn metals. All Zn centers of (I) and (II) adopted a slightly distorted tetrahedral geometry. Both complexes contain a hexanuclear Zn2N4 ring, but their ring structures are different. Complex (I) possesses a boat geometry, while complex (II) has a nearly planar structure. The Zn-bound chlorides of complex (I) form intermolecular N-H···Cl hydrogen bonds that link neighboring molecules. In complex (II), the O atoms in the nitrate groups are hydrogen-bonded to the DAT ligand via O···H-N linkages. Both complexes exhibit blue emissions in the solid state at ambient temperature. They were evaluated as anticancer agents in HeLa, NCCIT, and MCF-7 cancer cell lines, exhibiting promising anticancer activities.