One-dimensional supramolecular columnar structure of trans-syn-trans-dicyclohexano[18]crown-6 and organic ammonium cations

Abstract

Supramolecular crystals having one-dimensional (1d) columnar structures were constructed by using supramolecules based on tst-DCH[18]crown-6 (tst-DCH = trans-syn-trans-dicyclohexano). In the crystal of (Ani⁺)(tst-DCH[18]crown-6)[Ni(dmit)₂]⁻ (1) and (m-FAni⁺)(tst-DCH[18]crown-6)[Ni(dmit)₂]⁻ (2) (Ani⁺ = anilinium⁺, m-FAni⁺ = m-fluoroanilinium⁺, dmit²⁻ = 2-thioxo-1,3-dithiole-4,5-dithiolate), the tst-DCH[18]crown-6 formed supramolecular cations with Ani⁺ and m-FAni⁺, respectively, through N–H⋯O hydrogen bonds. The planar conformation of tst-DCH[18]crown-6 molecules in the crystals provided bidirectional hydrogen bonding from the upper and lower side of the molecule that were the driving forces for the construction of the 1d supramolecular architecture. The results provided a method to control arrangements of crown ether-based supramolecules in 1d columns that could be used for channels and/or molecular nanomachines such as molecular rotators.