Three different pillared assemblies with abundant topological architectures based on 4-sulfobenzoic ligand

One unprecedented three-dimensional 4-sbe complex [K(4-sbe)]n (1) and two proton-transfer compounds of 4-Hsb with amines, named as [(4-Hsb)·(NH4)·(H2O)]n (2) and {[(4-Hsb)]2·(H2bpe)·2(H2O)}n (3) have been synthesized and characterized by single-crystal X-ray analyses, elemental analyses, IR spectra, TG analyses, and fluorescence studies, where 4-sbe is 4-sulfobenzoic ester, 4-Hsb is 4-sulfobenzoate monoanion and H2bpe is protonated 1,2-bis(4-pyridyl)ethylene. All of the complexes share the common pillared architectures. Complex 1 is the first example of 4-sbe complexes with a 5-c bnn hexagonal BN net. In contrast, compounds 2 and 3 are two hydrogen-bonded 3D structures. In 2, 4-Hsb ligands brace the adjacent layers constructed by NH 4 + and water molecules through hydrogen bonds, generating a new 4, 5, 9-c 3-nodal net. In 3, H2bpe species further assemble the 2-D hydrogen-bonding network comprising of 4-Hsb and water molecules into a 3D InS net with channels. Basically, 4-sbe/4-Hsb either coordinates to metal centers or serves as hydrogen-bonding acceptors/donors giving 5, 9 and 4-connected nodes in the topological networks of compounds 1–3 respectively. Solid state properties such as luminescence and thermal stability of the complexes have been investigated.