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Systematic variation of the 1,4‐dioxane (dx) concentration during the precipitation of sparingly soluble [MgBr2(dx)2] from ethereal Grignard solutions of RMgBr has allowed the structural investigation of crystallized [R2Mg(dx)n] (n=1, 1.5, 2, and 3), which form during this dioxane method, depending on the bulkiness of R. The numbering of the complexes explored in this study is based on the number n of dioxane molecules per magnesium atom, followed by the substituent R; an apostrophe denotes coordination polymers. The following derivatives were studied by X‐ray crystal‐structure determination and NMR spectroscopy: n=1: [Me2Mg(μ‐dx)]∞ (1′‐Me) and [nPr2Mg(μ‐dx)]∞ (1′‐nPr); n=1.5: [{iPr2Mg(dx)}2(μ‐dx)] (1.5‐iPr), [{oTol2Mg(dx)}2(μ‐dx)] (1.5‐oTol), and [(Me3Si‐C≡C)2Mg(dx)1.5]∞ (1.5′‐C2SiMe3); n=2: [tBu2Mg(dx)2] (2‐tBu) and [oTol2Mg(dx)2] (2‐oTol); n=3: [Ph2Mg(dx)3] (3‐Ph). In the structure types 1′, 1.5, and 2, the magnesium atom exhibits the coordination number 4, whereas pentacoordinate metal atoms are observed in types 3 and 1.5′. The structure type 2′ is realized for [(Ph‐C≡C)2Mg(dx)2]∞ (2′‐C2Ph), [MgCl2(dx)2]∞ (2′‐Cl), and [MgBr2(dx)2]∞ (2′‐Br) with hexacoordinate metal atoms. The solubility of the dioxane adducts in common organic solvents strongly depends on the degree of aggregation with the solubility decreasing from molecular to strand to layer structures. [ABSTRACT FROM AUTHOR]

α,α′,α″,α′″-meso-Tetrahexyltetramethyl-calix[4]pyrrole is easily obtained as a single diastereomer in a one-pot reaction. It exhibits enhanced solubility in organic solvents, including aliphatic solvents, relative to its parentmeso-octamethylcalix[4]pyrrole (1). Somewhat surprisingly, the tetrahexyl derivative2complexes with tributylmethylammonium chloride in chloroform more strongly than does1as shown by NMR titrations. However,1and2exhibit comparable complexation strength in extraction experiments, the difference between the NMR and extraction results being attributed to the effect of organic-phase water in the extraction systems. Mass-action analysis indicates the formation of the predominant complex TBMA+(1or2)Cl−in both NMR and extraction systems, and equilibrium constants are reported. x-Ray crystal structures were obtained for the free ligand2and its complex with tetramethylammonium chloride. The free ligand crystallises in the 1,3-alt conformation with equatorial hexyl arms. In the chloride complex with2in its cone conformation, the hexyl arms adopt an axial orientation, enveloping the anion. DFT calculations show this binding conformation to be the most stable, mostly owing to destabilising steric interactions involving the pyrrole C–H and alkyl C–H groups positioned equatorially. [ABSTRACT FROM AUTHOR]

Novel phosphorous triazatetrabenzocorrole (4) bearing non-peripheral octatrifluorobutoxy groups was successfully synthesized, with an aim to develop potential far-red sensitizer for dye sensitized solar cells. The dye was characterized by ¹H NMR, IR, mass, and UV-vis spectral techniques. It showed excellent solubility in majority of common organic solvents. Aggregation behavior of the dye 4 was investigated in several solvents with increasing dielectric constants. This dye-4 was found to be adsorbed on the nanoporous TiO2 via axial ligation. Further implication of structure of dye due to incorporation of CF3 group on the energy levels was evaluated by theoretical and experimental approaches. The intense far-red absorption of dye 4 including its excellent solubility and proper control of its energy levels makes it a promising candidate for its application as sensitizer in dye sensitized solar cells. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a new hexadeca substituted zinc phthalocyanine 4 bearing hexyloxy groups in nonperipheral positions and 3-(diethylamino)phenoxy groups in peripheral positions and its corresponding water-soluble octacationic derivative 5 have been reported. The new compounds have been characterized by elemental analysis, IR, UV, NMR and mass spectra. Zinc phthalocyanine showed excellent solubility in organic solvents of wide polarity range due to its amphiphilic nature and it enabled us to carry out detailed UV–Vis studies in different solvents. Octacationic zinc phthalocyanine 5 was soluble in DMF, DMSO and water. UV–Vis spectra of 5 in DMSO, DMF and water showed sharp Q band absorption as an indication of monomeric form even in aqueous media. This property of water-soluble non-aggregating zinc phthalocyanine is promising as a photosensitizer in Photodynamic Therapy of Cancer. [Copyright &y& Elsevier]

Abstract: 1,2-Bis (2-oxo-5,5-dimethyl-1,3,2-dioxyphosphacyclohexyl-2-imino) ethane (BPEA) was prepared, and characterized by elemental analysis (EA), mass spectra (MS), infrared spectroscopy (IR) and nuclear magnetic resonance (NMR). The melting point and the enthalpy of fusion of BPEA were performed on differential scanning calorimetry (DSC), and the thermal stability of BPEA was tested by thermogravimetric analysis (TGA). The solubility of BPEA in selected solvents was measured by a static analytical method. The experimental data were correlated with different thermodynamic models, such as the empirical equation and non-random two liquid (NRTL), Wilson, Scatchard–Hildebrand, and universal quasi chemical (UNIQUAC) equations. The calculated results showed good agreement with the experimental data in the temperature range studied. [Copyright &y& Elsevier]

Abstract: Developing new green solvents is one of the key subjects in Green Chemistry. Ionic liquids (ILs) and deep eutectic solvents, thus, have been paid great attention to replace current harsh organic solvents and have been applied to many chemical processing such as extraction and synthesis. However, current ionic liquids and deep eutectic solvents have still limitations to be applied to a real chemical industry due to toxicity against human and environment and high cost of ILs and solid state of most deep eutectic solvents at room temperature. Recently we discovered that many plant abundant primary metabolites changed their state from solid to liquid when they were mixed in proper ratio. This finding made us hypothesize that natural deep eutectic solvents (NADES) play a role as alternative media to water in living organisms and tested a wide range of natural products, which resulted in discovery of over 100 NADES from nature. In order to prove deep eutectic feature the interaction between the molecules was investigated by nuclear magnetic resonance spectroscopy. All the tested NADES show clear hydrogen bonding between components. As next step physical properties of NADES such as water activity, density, viscosity, polarity and thermal properties were measured as well as the effect of water on the physical properties. In the last stage the novel NADES were applied to the solubilization of wide range of biomolecules such as non-water soluble bioactive natural products, gluten, starch, and DNA. In most cases the solubility of the biomolecules evaluated in this study was greatly higher than water. Based on the results the novel NADES may be expected as potential green solvents at room temperature in diverse fields of chemistry. [Copyright &y& Elsevier]

Abstract: Molecular level characterization of complex biopolymers in nature is a key element to understanding the composition of natural organic matter (NOM) and fossil organic matter formation, such as kerogen and coal. Characterization of such geopolymers is difficult due to their heterogeneity and insolubility in common aqueous or organic solvents. Here, a strategy for extracting a representative sample is presented using the combined techniques of nuclear magnetic resonance (NMR) and Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) for chemical analysis and characterization of NOM. A variety of NOM samples (wood, kerogen, bitumen, whole sediments) are shown as examples for implementing the strategy, which include solvent extractions using pyridine. For most samples, the extracts are confirmed to be chemically representative of the insoluble solid, by comparing the liquids NMR spectrum of the extract to that of the whole, unfractionated NOM utilizing high resolution magic angle spinning (HRMAS) NMR. To assist in unambiguous peak assignment, a technique for post acquisition spectral denoising, using wavelet transformation (WT), is also employed on the 1D and 2D NMR spectra. The findings from the NMR data lay a foundation for the subsequent electrospray ionization FTICR-MS analysis of the pyridine extracts, since this instrument has the limitation of only analyzing liquid samples. The FTICR-MS analyses can, therefore, be used to molecularly represent the structural components of the NOM. Various compositional insights have been obtained on these samples, indicating the efficacy of the analytical techniques used. [Copyright &y& Elsevier]

Abstract: Four new asymmetric Polyhedral Oligomeric SilSesquioxanes (POSS) with the formula (Aryl)Phenyl7Si8O12, where Aryl = 1-naphthyl, 2-naphthyl, 9-phenanthrenyl, and 1-pyrenyl, have been synthesized in reasonable yield and high purity. These compounds were characterized with 1H, 13C, 29Si NMR and elemental combustion analysis. These compounds possess polycyclic aromatic functionality, which disrupts symmetry to improve solubility in organic solvents and aromatic polymers, without significant impact on thermal stability. [Copyright &y& Elsevier]

Abstract: A series of acidic task-specific ionic liquids 1-R2-2-R1benzimidazolium tetrafluoroborate (R1 =Me, R2 =Me, Et, Pr-n, Bu-n, Pen-n) were prepared by simple acid-base neutralization of the corresponding 1-alkylbenzimidazole and tetrafluoroboric acid. The compounds were characterized by FTIR spectra, elemental analysis, 1HNMR spectra and thermogravimetric analysis. These new ionic liquids are nonvolatile, and have potential use as alternatives to conventional organic solvents due to their solubility and thermal stability. These novel tetrafluoroborate salts show good catalytic activity to esterification of carboxylic acids with alcohols under mild reaction conditions, which could maintain good catalytic performance after recycling at least six times. Furthermore, a crystal of one compound, [H-bmBim]BF4, was prepared, with the crystal structure determined by X-ray diffraction analysis. The molecular structure is formed by weak π-π interactions and intermolecular hydrogen bonds between the benzimidazole rings, yielding a three-dimensional net-like supramolecule. [Copyright &y& Elsevier]

Abstract: The synthesis of novel metal-free (4) and metallophthalocyanines (5, 6, 7 and 8) were prepared by cyclotetramerization of a novel 4-[2-(1-naphthyloxy)ethoxy]phthalonitrile (3). New substitute phthalocyanines showed the enhanced solubility in organic solvents. The new compounds were characterized by a combination of IR, 1H NMR, 13C NMR, UV–Vis and MS spectral data. [Copyright &y& Elsevier]

Abstract: The syntheses of new three phthalonitriles (1, 2 and 3), together with photophysical and photochemical properties of the resulting peripherally and non-peripherally tetrakis- and octakis 3,4-(methylendioxy)-phenoxy-substituted zinc phthalocyanines (4, 5 and 6) are described for the first time. Complexes 4, 5 and 6 have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. Complexes 4, 5 and 6 have good solubility in organic solvents such as CHCl3, DCM, DMSO, DMF, THF and toluene and are mainly not aggregated (except for complex 6 in DMSO) within a wide concentration range. General trends are described for singlet oxygen, photodegradation, fluorescence quantum yields, triplet quantum yields and triplet life times of these complexes in DMSO and toluene. Complex 4 has higher singlet oxygen quantum yields, fluorescence quantum yields, triplet quantum yields and triplet life times than complexes 5 and 6. The effect of the solvents on the photophysical and photochemical parameters of the zinc(II) phthalocyanines (4, 5 and 6) are also reported. [Copyright &y& Elsevier]

Styrenic dendrons functionalized with ferrocenyl and chloromethylsilyl termini were synthesized and polymerized by the AIBN-initiated radical polymerization procedure yielding a ferrocenyl dendronized polymer and a chloromethylsilyl dendronized polymer, respectively. The latter polymer was functionalized with ferrocenyl groups using “click” chemistry. The ferrocenyl dendronized polymers are soluble in common organic solvents such as tetrahydrofuran, dichloromethane, and chloroform. They show a reversible ferrocenyl wave in cyclic voltammetry (CV) and form derivatized Pt electrodes. Their sizes and shapes were examined by size exclusion chromatography (SEC), atomic force microscopy (AFM), dynamic light scattering (DLS) and DOSY 1H NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: Novel lipophilic (diamine)platinum(II) complexes of salicylate derivatives as the leaving groups were synthesized and characterized by elemental analysis, FAB+-MS, FT-IR, and 1H NMR spectroscopy. Most of the resulting platinum complexes had high solubility in organic solvents such as ethanol, acetone, and ether, and had right partition coefficient suited to be encapsulated in liposomes. The pertinent complexes were evaluated for their in vitro cytotoxicity against A549 human lung carcinoma and SGC-7901 human gastric carcinoma cell lines. They showed better cytotoxic activity than carboplatin and oxaliplatin. [Copyright &y& Elsevier]