Effect of hydrogen‐bonding in the development of high‐affinity metal ion complexants: Polymer‐bound phosphorylated cyclodextrin

In a series of phosphorylated polyols bound to a polystyrene support, the position of the FTIR band assigned to hydrogen bonding between the ? OH and phosphoryl oxygen correlates with the affinity of that phosphoryl oxygen for metal ions. Polymer with phosphorylated β‐cyclodextrin (pCD) ligands is now reported as a further test of this correlation. The metal ion affinity is probed with the uranyl ion. pCD is the most red‐shifted of a series of five phosphorylated polyols: the strongest polyol had been phosphorylated pentaerythritol (pPE) with a band at 873 cm^?1; pCD has a band at 868 cm^?1. Consistent with the FTIR bands, pCD has a significantly higher affinity for the uranyl ion than pPE: the percents complexed from a 10^?4M uranyl solution in a background of 1.0N HNO₃, HCl, and H₂SO₄ are 94.7%, 90.5%, and 93.6%, respectively, for pCD and 68.6%, 52.1%, and 40.1%, respectively, for pPE. This further supports the hypothesis that the strong complexing ability of phosphorylated polyols is due to activation of the phosphoryl oxygen through hydrogen bonding between the P?O and the ? OH groups within the polyol. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011