Monosubstituted pillar[5]arene functionalized with (amino)phosphonate fragments are “smart” building blocks for constructing nanosized structures with some s- and p-metal cations in the organic phase

Monosubstituted pillar[5]arenes containing a phosphonate fragment were successfully obtained in good yields. It was found that the introduction of bulky fragments containing tetra-coordinated pentavalent phosphorus atoms prevents self-Assembly of monosubstituted pillar[5]arenes and the formation of supramolecular polymers. Pillar[5]arenes with phosphonate and 1-Aminophosphonate substituents demonstrated recognition towards Na ⁺, K ⁺, Cs ⁺ and Pb ²⁺. Their ability to form complexes with these cations was evaluated by UV spectroscopy. Dynamic light scattering (DLS) revealed the formation of aggregates with K ⁺, Cs ⁺ and Pb ²⁺. It was established that the substituent at the α-carbon atom of the aminophosphonate fragment played a significant role in Pb ²⁺ binding. DLS and transmission electron microscopy revealed that Pb ²⁺-induced aggregation formed particles with a monodisperse distribution of 0.02-0.23 and a hydrodynamic diameter of 58-178 nm.