Competing Supramolecular Interactions Give a New Twist to Terpyridyl Chemistry: Anion- and Solvent-Induced Formation of Spiral Arrays in Silver(I) Complexes of a Simple Terpyridine

Abstract

Multiple competing molecular interactions (metal–ligand, π‐stacking and hydrogen‐bonding) in the silver(I) complexes of 4′‐thiomethyl‐2,2′:6′,2″‐terpyridine give rise to a range of different molecular architectures, in which the metal–ligand coordination requirements are satisfied in quite different ways. Polynuclear supramolecular spirals, aggregated mononuclear and aggregated dinuclear units are all structurally characterised. The metallo‐supramolecular architecture obtained displays a remarkable dependence both on the choice of non‐coordinated anion and the type of solvent used (coordinating or non‐coordinating). The anion dependence is particularly surprising, since the anions are not integrated into the centre of the supramolecular structure. The solution behaviour is also solvent and anion dependent, with aggregation of planar mononuclear cations observed in acetonitrile, but oligonuclear spiral species implicated in nitromethane. The extraordinarily variable geometries of these systems suggest that they provide a novel example of the “frustration” principle, in which opposing tendencies cannot simultaneously be satisfied and identify an alternative approach to the design of metallo‐supramolecular systems whose structure is responsive to external agents.

Square planar silver(I) complexes: A rare but increasingly observed stereochemistry for silver(I)

“…After refluxing AgOAc and 4 -thiomethyl-terpyridine (tpysm) in MeOH the filtrate was treated with an excess of NH 4 PF 6 to give a white precipitate of [Ag(tpysm)(MeCN)]PF 6 [60]. (Fig.…”

Electrochemical Synthesis and Structural Characterization of a Novel Mixed-valence Copper (I)-copper (II) Complex: {[Bis(ethylenediamine) Copper (II)] Bis[diiodocuprate (I)]}

“…The design of complex molecular architectures based on transition metal atoms and organic ligands is an important goal for synthetic chemistry as it provides the opportunity to control or encode the properties of a material at the molecular level [1]. Suitable organic ligands favoring structure-specific self-assembly are the bases for the construction of coordination architectures.…”

In situ hydrothermal syntheses, crystal structures and luminescent properties of two novel zinc(II) coordination polymers based on tetrapyridyl ligand

“…The design of coordination polymer architectures is an important goal for synthetic chemistry as it provides an opportunity to control the properties of materials at the molecular level [1][2][3]. The most successful strategies for the design of coordination polymers are based on a building block approach because final structural frameworks can dramatically change when the organic building blocks vary [4,5].…”