A C-shaped p-sulfonatocalix[4]arene-based supermolecule exhibiting mutual-inclusion and bilayer insertion of dipicolinate

Abstract

A p-sulfonatocalix[4]arene-based supermolecule, [Ce₃(PDA)₄(C4AS)₂·13H₂O](NO₃)·25H₂O 1 was prepared by slow evaporation of a solution of Ce(NO₃)₃·6H₂O, 2,6-pyridinedicarboxylic acid (PDA) and pentasodium p-sulfonatocalix[4]arene salt. The molecular and crystal structure of 1 was determined by single crystal X-ray structural analysis and characterized by thermal methods (TG, DSC and hot-stage microscopy) and Hirshfeld analysis. The supermolecule is C-shaped with alternating calixarene and PDA ligands linked to three Ce(III) cations. The supermolecules exhibit mutual-inclusion via its PDA ligands with the remaining PDA ligands inserted into the calixarene bilayer. The bilayer consists of an “up–down” arrangement of calixarenes, with the inserted PDA ligands effecting a zig-zag propagation of the calixarenes within the bilayer.