Crowned spiropyran fluoroionophores with a carboxyl moiety for the selective detection of lithium ions was written by Stubing, D. B.;Heng, S.;Abell, A. D.. And the article was included in Organic & Biomolecular Chemistry in 2016.Category: ethers-buliding-blocks This article mentions the following:
The absorbance and fluorescence spectra of carboxylated spiropyrans containing methyl-1-aza-12-crown-4, methyl-1-aza-15-crown-5, methyl-1-aza-18-crown-6 moieties are compared. Characteristic changes in spectra after addition of the alkali metal salts of Li+, Na+, K+ and Cs+ were observed Chromism induced by the binding of the metal cations was observed as an increase in absorbance and fluorescence. Of these metal cations, the Li+ ion produced the largest change in all three spiropyran systems. Reversible photoswitching of the spiropyran-metal complexes was observed on irradiation with alternating 352 nm UV and white light. This results in reversible fluorescence based sensing of lithium ions with potential for use in a biol. sensor device. In the experiment, the researchers used many compounds, for example, 1,4,7,10-Tetraoxa-13-azacyclopentadecane (cas: 66943-05-3Category: ethers-buliding-blocks).
1,4,7,10-Tetraoxa-13-azacyclopentadecane (cas: 66943-05-3) belongs to ethers. The oxygen atom in ethers are more electronegative than carbon, thus the hydrogens which are alpha to the ethers are more acidic than the simple hydrocarbons. Ethers are good solvents partly because they are not very reactive. Most ethers can be cleaved, however, by hydrobromic acid (HBr) to give alkyl bromides or by hydroiodic acid (HI) to give alkyl iodides.Category: ethers-buliding-blocks
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem