Synthesis and Metal‐Complexation Ability of Cross‐Linking Materials Containing Noria‐Templated Cavities with Pendant Carboxylic Acid Groups

Abstract

AbstractWe synthesized noria‐containing cross‐linking materials, Cross(Noria‐MA‐co‐DM[n]m), by radical polymerization of a noria derivative with pendant methacryloyl groups (noria‐MA) and α, ω‐alkanedimethacrylamides (DM[n], n=3, 6, 12) at feed ratios of noria‐MA/DM[n]=1/2.4, 1/12, and 1/24 (m=2.4, 12. and 24). Alkaline hydrolysis reaction of Cross(Noria‐MA‐co‐DM[n]m) removed the noria moieties to give corresponding cross‐linking materials, Cross‐COOH‐DM[n]m, containing noria‐templated fixed cavities with pendant carboxylic acid groups. Among the noria‐containing cross‐linking materials, Cross(Noria‐MA‐co‐DM[6]24) showed the greatest extent of removal of noria upon hydrolysis. Nitrogen and carbon dioxide absorption studies indicated that Cross(Noria‐MA‐co‐DM[6]24) contains fixed cavities, whereas Cross‐COOH‐DM[6]24 does not in the solid (unswollen) state. Examination of the inclusion‐complex‐forming ability of the synthesized cross‐linking materials using aqueous solutions of metal ions revealed that Cross‐COOH‐DM[6]24 has the greatest absorption capacity. These results indicate that Cross‐COOH‐DM[6]24 indeed contains noria‐templated cavities that can accommodate metal ions in aqueous solution.