In the past few years, spiropyran has emerged as the molecule-of-choice for the construction of novel dynamic materials. This unique molecular switch undergoes structural isomerisation in response to a variety of orthogonal stimuli, e.g. light, temperature, metal ions, redox potential, and mechanical stress. Incorporation of this switch onto macromolecular supports or inorganic scaffolds allows for the creation of robust dynamic materials. This review discusses the synthesis, switching conditions, and use of dynamic materials in which spiropyran has been attached to the surfaces of polymers, biomacromolecules, inorganic nanoparticles, as well as solid surfaces. The resulting materials show fascinating properties whereby the state of the switch intimately affects a multitude of useful properties of the support. The utility of the spiropyran switch will undoubtedly endow these materials with far-reaching applications in the near future.

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Spiropyran-based dynamic materials

A review. Physicochem. properties of ionic liqs. are discussed. Chem. and electrochem. reactivity in ionic liqs. is described including electrode reactions, electrode reaction kinetics, electrosynthesis, etc.

Electrochemical reactivity in room-temperature ionic liquids.

Ionic liquids are liquids composed completely of ions. In the past two decades, ionic liquids have been widely used as “green solvents” replacing traditional organic solvents for organic synthesis and catalysis. In addition, ionic liquids are playing an increasingly important role in separation science. In this Account, the application of ionic liquids in all areas of separation science including extractions, gas chromatography, and supported liquid membrane processes are highlighted.

Ionic liquids in separations.

Sequential separation of light rare-earth elements, thorium and uranium by miniaturized extraction chromatography: Application to isotopic analyses of silicate rocks

https://pure.mpg.de/pubman/item/item_1925102_4/component/file_1925101/562340.pdf

Poly(ionic liquid)s: Polymers expanding classical property profiles

Task-Specific Ionic Liquids for Metal Ion Extraction : Progress, Challenges, and Prospects

In conjunction with efforts to develop novel actinide extractants exhibiting solubility in supercritical carbon dioxide, the effect of adding silicon-based functionalities to diphosphonic acids has been investigated. Specifically, a series of silyl-substituted diphosphonic acids has been prepared and characterized, and their aggregation and metal ion extraction properties compared with alkyl-substituted diphosphonic acids, reagents previously demonstrated to be effective extractants of actinides from acidic aqueous media into various organic solvents. In addition, the influence of the number of methylene groups bridging the phosphorus atoms of the diphosphonic acids on their extraction behavior has been investigated. Variations in the extraction behavior of the compounds arising from differences in the number of bridging methylene groups have been shown to be attributable to a combination of factors, in particular, the aggregation state of the ligand, the size of the chelate rings formed upon complexation, the basicity of the phosphoryl group and the relative acidities of the ligands.

/pdf/aggregation-and-metal-ion-extraction-properties-of-novel-15jx8n886b.pdf

Aggregation and metal ion extraction properties of novel, silicon-substituted alkylenediphosphonic acids.

Efforts to improve the TALSPEAK (Trivalent Actinide Lanthanide Separation with Phosphorus-Reagent Extraction from Aqueous Komplexes) Process have considered, among other options, the replacement of...

Solvent structural effects on the solubility of bis(2-ethylhexyl)phosphoric acid (HDEHP) in room-temperature ionic liquids

In the proposed method, chloride is oxidized to chlorine gas and the transient absorbance signal of the latter is measured using atomic absorption instrumentation. Instead of the flame, a flow-through absorption cell is used. The method is rapid and direct. The detection limit is 14 μg/mL Cl.

Determination of Chloride by Molecular Absorption Spectrophotometry in the Gas Phase Following Oxidation

The rational design of ionic liquid-based metal ion separation systems requires either that the ion transfer properties of these systems be predictable from the known behavior of conventional organic solvents or that the mechanism(s) of ion transfer be understood at a fundamental level. With this in mind, we have examined the transfer of selected metal ions from acidic aqueous media into a series of N,N'-dialkylimidazolium-based room-temperature ionic liquids (RTILs) in the presence of crown ethers, neutral organophosphorus extractants, or β-diketones. The results obtained indicate that although certain aspects of metal ion extraction into RTILs parallel the behavior of conventional solvents, ionic liquids frequently play a more active role in the partitioning process, with ion exchange involving the cationic or anionic constituents of the ionic liquid comprising an important mode of ion transfer. The implications of this observation for the application of ILs as extraction solvents are described.

The Road to Partition — Mechanisms of Metal Ion Transfer into Ionic Liquids and Their Implications for the Application of Ionic Liquids as Extraction Solvents

Mark L. Dietz

Papers

Task-Specific Ionic Liquids for Metal Ion Extraction : Progress, Challenges, and Prospects

Aggregation and metal ion extraction properties of novel, silicon-substituted alkylenediphosphonic acids.

Solvent structural effects on the solubility of bis(2-ethylhexyl)phosphoric acid (HDEHP) in room-temperature ionic liquids

Determination of Chloride by Molecular Absorption Spectrophotometry in the Gas Phase Following Oxidation

The Road to Partition — Mechanisms of Metal Ion Transfer into Ionic Liquids and Their Implications for the Application of Ionic Liquids as Extraction Solvents