N-Alkyl Ammonium Resorcinarene Salts as High-Affinity Tetravalent Chloride Receptors
- University of Jyväskylä
N-Alkyl ammonium resorcinarene salts (NARYs, Y=triflate, picrate, nitrate, trifluoroacetates and NARBr) as tetravalent receptors, are shown to have a strong affinity for chlorides. The high affinity for chlorides was confirmed from a multitude of exchange experiments in solution (NMR and UV/Vis), gas phase (mass spectrometry), and solid-state (X-ray crystallography). A new tetra-iodide resorcinarene salt (NARI) was isolated and fully characterized from exchange experiments in the solid-state. Competition experiments with a known monovalent bis-urea receptor (5) with strong affinity for chloride, reveals these receptors to have a much higher affinity for the first two chlorides, a similar affinity as 5 for the third chloride, and lower affinity for the fourth chloride. The receptors affinity toward chloride follows the trend K1蠑K2蠑K3≈5>K4, with Ka=5011 m-1 for 5 in 9:1 CDCl3/[D6]DMSO. Completing the circle: N-Alkyl ammonium resorcinarene salts (NARYs) are high-affinity tetravalent chloride receptors. Competition experiments including multiple 1H NMR titration experiments reveal that NARYs have a higher affinity towards the first two Cl- ions, comparable affinity for the third Cl-, and lower affinity for the fourth Cl- compared to a known bis-urea receptor.
|Julkaisu||CHEMISTRY: A EUROPEAN JOURNAL|
|Tila||Julkaistu - 22 tammikuuta 2016|
|OKM-julkaisutyyppi||A1 Julkaistu artikkeli, soviteltu|