Anthraquinone‐1,8‐Derived (Pseudo‐) Crown and Lariat Ethers:Design and Applications as Fluorescent and Chromogenic Ion (Pair) Sensors

Abstract

Cyclic polyamine/ethers embedded with anthraquinone moieties and functional pendants, are structural analogues of crown ethers and (oxo‐) cyclams, and could be utilized as sensitive and selective chemosensors towards metal cations. Those pseudo‐ (similar but geometrically distinct) crown and lariat ethers show various cation‐binding patterns and stoichiometry, being modulated by donor type, cavity size and pendants’ chelating ability. The luminescent and chromogenic properties also differ a lot along with the derivation of the parental macrocycle. Methodological designing including synthesis and post‐functionalization through nucleophilic substitution, Mannich condensation etc., as well as the sensing performance of those pseudo‐crown and lariat ethers are summarized in this review, basing on the spectroscopic, voltammetric and X‐ray crystallographic determinations. Anion effect in sensing cations is evaluated according to the ion‐pair recognition theory. Those results shed some light on exemplifying the anions’ role in bioinorganic systems including metalloenzymes.

Enhanced molecular binding affinity toward aromatic dications by anthracene-derived crown ethers in water

“…Crown ethers with an aromatic skeleton that can form pseudorotaxane-like complexes have been widely studied in recent years, 16 and the introduction of sulfonate groups into the aromatic backbone of these crown ethers eventually results in the generation of negatively charged hosts with excellent water solubility and can strongly bind and recognize π-electron-deficient guests such as pyridinium ions and aromatic imides. 13–15 The association constants ( K a ) for these water-soluble complexes mainly range from 10 2 to 10 7 M −1 , depending on the extension of the π-stacking area and charge numbers.…”