Strapped calix[4]pyrrole as a lithium salts selective receptor through separated ion-pair binding.

A triazole-bearing strapped calix[4]pyrrole (1) was synthesized as a lithium salt selective ion pair receptor. 1H NMR spectral studies and X-ray crystallography showed that the capture of LiCl by 1 occurs via separated ion pair binding. Furthermore, lithium salts extracted by 1 could be solidified in the form of Li2CO3 through CO2 or K2CO3 treatment.