Designed supramolecular assembly of hydrogen-bonded anionic rosette layers

Self-assembly of five two-dimensional hydrogen-bonded honeycomb grids bearing the rosette motif has been conducted with the guanidinium cation and various anionic components as the building blocks, tetraalkylammonium ions being employed as the interlayer templates. The sinusoidal supramolecular guanidinium-carbonate (1:1) rosette layer reported previously has been induced to adopt a nearly planar configuration using 1H-imidazole-4,5-dicarboxylate as an auxiliary template and spacer. A novel three-component guanidinium-boric acid-carbonate (1:2:1) wavy layer has been constructed, which features two distinguishable rosette motifs. Deviating from conventional topological design, the generation of new rosette layers, albeit highly distorted, has also been accomplished with guanidinium ions and anionic building blocks (1,2-dithiosquarate and dianionic form of 1,1′-biphenyl-2,2′,6, 6′-tetracarboxylate) that do not conform to C₃-symmetry.