Anionic Head Containing Oxacalix[2]arene[2]triazines: Synthesis and Anion−π-Directed Self-Assembly in Solution and Solid State

A series of oxacalix[2]­arene[2]­triazines
bearing one anionic head
such as carboxylate, sulfonate, sulfate, and phosphate were synthesized.
With the anionic head and complementary V-shape electron-deficient
cavity, these macrocycles can serve as dual building units, and their
anion−π directed self-assembly was investigated. The
formation of oligomeric aggregates in solution was revealed by nuclear
magnetic resonance, dynamic light scattering, and mass spectroscopy.
Crystal structures further confirmed chainlike assembly formation
directed by anion−π interactions.