Guests inducing p-sulfonatocalix[4]arenes into nanocapsule and layer structure

Reaction of sodium p-sulfonatocalix[4]arene and TbCl3 in the presence of 2,2′-bipyridine-N,N′-dioxide (bpdo) gives the 2:1 supramolecular nanocapsule [[Tb(bpdo)2·4H2O]3+⋂{p-sulfonatocalix[4]arene4−}2], which further interacts with the [Tb(bpdo)4]3+ through charge-assisted π-stacking interactions forming a channel structure 1. In further investigation, we tried to use the terpyridine-1,1′,1′-trisoxide (tpto) instead of bpdo. Although we failed to isolate a supramolecular capsules based on the tpto, lanthanide and p-sulfonatocalix[4]arene, a layer structure derived from p-sulfonatocalix[4]arene with an unusual [Cu(tpto)2]2+ incorporation into the cavity of the calixarene and an outside [Cu(tpto)2]2+ balancing the charge, has been obtained. Fluorescence spectra show clearly that compound 1 possesses the luminescence characteristics of Tb3+ and the ligand bpdo can sensitize Tb3+ ion. Gas sorption experiment shows the channel structure 1 has highly selective gas sorption properties for water and methanol.