Thiacalix[4]arene–potassium assemblies: a supramolecular architecture based on coordination polymers and a dimeric structure based on triangular pyramidal arrangements

Abstract

The crystal structures of two potassium metal complexes {[K₄(1·2H)₂]·(MeOH)₂·(H₂O)_1.5}₂ (2) and {[K₈(1)₂]·(μ₂-n-BuOH)₂·(n-BuOH)₄} (3) of partially- or fully-deprotonated p-H-thiacalix[4]arenes were determined by single-crystal X-ray diffraction studies. In the crystal structure of complex 2, a coordination polymer was formed by continuing of complementary metal coordination and π-stacking interactions between the base dimer and a ca. 90° turned neighboring dimer. In addition, coordinated methanol molecules in the polymer play a significant role in the construction of a supramolecular architecture. In the case of the complex 3, eight potassium cations exhibited two triangular pyramidal arrangements, which are bridged at planar phenoxide oxygen atoms and linking sulfur atoms belonging to the thiacalixarene ligands further support via alkali-metal cation–π interactions in the thiacalixarene cavities.