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The self-assembly of structurally discrete entities, and supramolecular chemistry in general, continues to expand into the aqueous realm. To do so, however, requires a firm understanding of the properties of aqueous solution, and how these 'change the rules' for binding and assembly relative to organic solvents. In this mini-review we highlight the state-of-the-art understanding of the supramolecular properties of water, and how these influence the design of hosts and self-assembling systems. [ABSTRACT FROM AUTHOR]

Abstract: Interest in the development of solvent-impregnated resins (SIRs) and their applications for the separation of metal ions and organic compounds from water in the form of a hybrid polymeric adsorbent material has intensified over the past thirty years. SIRs are particulate adsorbers that possess a combination of the advantageous features of both liquid–liquid extraction and ion exchange and this renders them applicable to a wide range of potential liquid–solid separation and recovery processes. This paper reviews the extensive published literature on methods of synthesis of SIRs, attempts to stabilize hybrid solvent-impregnated resins and various applications of SIRs. [Copyright &y& Elsevier]

Abstract: It has recently been shown that the use of strong organic solvents as diluent is possible in RPLC, provided that the solvent used as diluent is retained more strongly by the column than the analytes in the sample. In this study, the phenomenon was further studied experimentally using several water-immiscible solvents (ethyl acetate, isopropyl acetate, and methyl isobutyl ketone) and several model analyte compounds. In all cases, analyte peak distortion was minimal provided the analyte eluted earlier than the diluting solvent, in contrast to substantial broadening and distortion when the analyte eluted after the diluting solvent. The potential analytical utility of this approach is discussed, and an example of a practical application is also presented. [Copyright &y& Elsevier]

To assess the risk and fate of fullerene C60 in the environment, its water solubility and partition coefficients in various systems are useful. In this study, the log KOW of C60 was measured to be 6.67, and the toluene-water partition coefficient was measured at log Ktw = 8.44. From these values and the respective solubilities of C60 in water-saturated octanol and water- saturated toluene, C60's aqueous solubility was calculated at 7.96 ng/L(1 .11 x 10-11 M) for the organic solvent-saturated aqueous phase. Additionally, the solubility of C60 was measured in mixtures of ethanol-water and tetrahydrofuran-water and modeled with Wohl's equation to confirm the accuracy of the calculated solubility value. Results of a generator column experiment strongly support the hypothesis that clusters form at aqueous concentrations below or near this calculated solubility. The KOW value is compared to those of other hydrophobic organic compounds, and bioconcentration factors for C60 were estimated on the basis of KOW. [ABSTRACT FROM AUTHOR]

Abstract: A highly efficient and facile method has been described for the synthesis of substituted 2-aminothiazoles in water without any added catalyst or co-organic solvent. The reaction was carried out at ambient temperature and the products were obtained in excellent isolated yields. The developed protocol is successfully applied for the preparation of an anti-inflammatory drug, fanetizole. [Copyright &y& Elsevier]

Abstract: The asymmetric transfer hydrogenation of nonfunctionalized aromatic ketones catalyzed by Ru-TsDPEN was performed successfully in a mixture of poly(ethylene glycol) (PEG) and water. High activity and enantioselectivity were obtained, which were better than or comparable to those obtained in conventional organic solvents. The unmodified catalyst could be easily recovered after extraction of the reduced product with a less polar solvent such as hexane, and was reused at least 14 times without obvious loss in enantioselectivity. These results indicate that the inexpensive and non-toxic aqueous PEG can serve as a new means for the immobilization of Ru-TsDPEN catalyst and related variants without calling for catalyst modification. [Copyright &y& Elsevier]

Abstract: The growing trend both to avoid the use of organic solvents and reduce the time needed to extract pollutants from environmental solid samples has led to the use of water assisted by auxiliary energies for leaching. The most common of the auxiliary energies used are high pressure–high temperature, microwaves and ultrasounds. One of the most interesting aspects of the use of water in combination with auxiliary energies is the possibility of coupling extraction with other steps of the analytical process, thus enabling partial or total automation of the analytical process, so it is expedited. The addition of reagents (such as surfactants, acids, etc.) to water enlarges its field of application and provides an additional way of shortening the leaching time; thus allowing the establishment of environmental friendly methods. A review about the potential of water as extractant and its main applications so far is here presented. [Copyright &y& Elsevier]

Two thioxanthone-based fluorescent probes exhibited prominent solvatofluorochromism, and they were further found to be useful as fluorescence indicators for the qualitative and quantitative detection of low-level water content in various solvent media. [ABSTRACT FROM AUTHOR]

Abstract: The addition of amines to conjugated alkenes has been carried out in water at room temperature very efficiently without any catalyst. Significant rate acceleration of this reaction is observed in water compared to organic solvents. [Copyright &y& Elsevier]