Functional heterocyclic molecular inclusion in p-sulfonatocalix[5]arene and lanthanide(III) complexes

Lanthanide(III) ions form complexes readily with water-soluble p-sulfonatocalix[5]arene (SC5) in the solid-state with the calixarene assembled into the bilayer arrangement having either a dense packing of the calixarenes or a grid-like arrangement depending on the nature of the lanthanide incorporated. The larger size of the macrocycle adopts the cone conformation and is capable to encapsulate at least one large heterocyclic molecule or more than one smaller molecules within the capsular cavity without inducing conformational change to the calix[5] arene. Different heterocyclic molecules of various size and charge notably 5,7,4'-trimethoxy flavanone (TMFLV) and 1-hexyl-3-methylimidazolium (HMIM) are examined in this study.