Reaction of aminomethylcavitands with iso(thio)cyanates gives (thio)urea-functionalized resorcinarene cavitands, which represent a novel class of neutral anion receptors. The complexation of halide anions has been studied both with infrared and 1H NMR spectroscopy. The receptors have a small preference for chloride over the other halides; p-fluorophenylthiourea cavitand 8a gives the highest association constant (Kass = 4.7 × 105 M-1 with chloride in CDCl3). A cooperative effect of the ligating (thio)urea moieties is indicated by the lower affinity of the corresponding tris(thio)urea-functionalized cavitands. For the first time facilitated membrane transport of halide anions through supported liquid membranes is achieved.
Boerrigter, H., Grave, L., Nissink, J. W. M., Chrisstoffels, L. A. J., van der Maas, J. H., Verboom, W., ... Reinhoudt, D. N. (1998). (Thio)urea resorcinarene cavitands: Complexation and membrane transport of halide anions. Journal of organic chemistry, 63(13), 4174-4180. https://doi.org/10.1021/jo972127l