Self-assembly of new three-dimensional molecular architectures constructed from silver(i)–hexamethylenetetramine layers with supramolecular interactions

Abstract

Three new co-ordination polymers [Ag(μ₃-hmt)](abs) 1, [Ag(μ₃-hmt)](ns)·0.5(benzene)·2H₂O 2, and [Ag(μ₃-hmt)]₂[Ag(NH₃)₂]₂(pma)·3H₂O 3 (hmt = hexamethylenetetramine, abs = 4-aminobenzenesulfonate, ns = 2-naphthalenesulfonate and pma = 1,2,4,5-benzenetetracarboxylate), have been prepared and structurally characterised. In these compounds, the metal ions and the μ₃-hmt ligands are covalently interconnected into hexagonal two-dimensional layers, whereas supramolecular interactions, such as weak Ag⋯O contacts, hydrogen bonds and/or π–π stacking, play an important role in the construction of three-dimensional molecular architectures. The observation of dimeric [Ag(NH₃)₂]₂²⁺ species trapped in such co-ordination surroundings in 3 is unprecedented.