Synthesis and structural features of sulfur-substituted calix[4]pyrrole for a bottom-up control of the substrate-directed self-assembly of supramolecular structures

The synthesis of six new calix[4]pyrroles, containing sulfur-substituted phenylene units is reported. Halogen-anions and organic aromatic mono- and bis-anions have been selected to explore the formation of host-guest complexes and the possible self-assembly of multi-component structures with the six calixpyrroles. The type of aryl substitution modulates the strength of binding and the selectivity towards different anions and, in some cases, the combination of receptors and bis-anionic precursors, offers a way to build systems in which capsular assemblies are observed.