60835-71-4Relevant articles and documents
Cooperative Transport and Selective Extraction of Sulfates by a Squaramide-Based Ion Pair Receptor: A Case of Adaptable Selectivity
Dobrzycki, ?ukasz,Karbarz, Marcin,Romański, Jan,Wilczek, Marcin,Zaleskaya, Marta
, p. 13749 - 13759 (2020)
The use of a squaramide-based ion pair receptor offers a solution to the very challenging problem of extraction and transport of extremely hydrated sulfate salt. Herein we demonstrate for the first time that a neutral receptor is able not only to selectively extract but also to transport sulfates in the form of an alkali metal salt across membranes and to do so in a cooperative manner while overcoming the Hofmeister bias. This was made possible by an enhancement in anion binding promoted by cation assistance and by diversifying the stoichiometry of receptor complexes with sulfates and other ions. The existence of a peculiar 4:1 complex of receptor 2 with sulfates in solution was confirmed by UV-vis and 1H NMR titration experiments, DOSY and DLS measurements, and supported by solid-state X-ray measurements. By varying the separation technique and experimental conditions, it was possible to switch the depletion of the aqueous layer into extremely hydrophilic or less lipophilic salts, thus obtaining the desired selectivity.
DESALINATION OF WATER USING A COMPLEXING AGENT ATTACHED TO A MAGNETIC NANOPARTICLE
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Page/Page column 89, (2022/03/09)
There is disclosed, a desalination apparatus making use of a particles including covalently bonded functionalized magnetic nanoparticles coupled to a complexing agent. For example, the complexing agent may include a crown ether. The particles are optionally used for removing salt from water, for example sea water. The apparatus optionally includes a magnet for magnetic filtering, concentrating and/or removing the particles and/or contaminant (e.g., salt). In some embodiments, the salt is then separated back from the particles using UV light. The remaining unclarified water may be washed out with the contaminant and/or used for salt production and/or disposed of (e.g., dumped back to the sea). Optionally, the particles are regenerated. For example, the regenerated particulars may be reused for further desalination steps (e.g., further salt removal from the clarified water) to clarify new input water. Covalently bonded functionalized magnetic nanoparticles coupled to a complexing agent are also disclosed.
Chalcogen Bond Mediated Enhancement of Cooperative Ion-Pair Recognition
Bunchuay, Thanthapatra,Docker, Andrew,Eiamprasert, Utt,Surawatanawong, Panida,Brown, Asha,Beer, Paul D.
, p. 12007 - 12012 (2020/05/18)
A series of heteroditopic receptors containing halogen bond (XB) and unprecedented chalcogen bond (ChB) donors integrated into a 3,5-bis-triazole pyridine structure covalently linked to benzo-15-crown-5 ether motifs exhibit remarkable cooperative recognition of halide anions. Multi-nuclear 1H, 13C, 125Te and 19F NMR, ion pair binding investigations reveal sodium cation–benzo-crown ether binding dramatically enhances the recognition of bromide and iodide halide anions, with the chalcogen bonding heteroditopic receptor notably displaying the largest enhancement of halide binding strength of over two hundred-fold, in comparison to the halogen bonding and hydrogen bonding heteroditopic receptor analogues. DFT calculations suggest crown ether sodium cation complexation induces a polarisation of the sigma hole of ChB and XB heteroditopic receptor donors as a significant contribution to the origin of the unique cooperativity exhibited by these systems.