Jack of all trades: anion and transition metal binding by bis-triazole receptors

Abstract

Four acyclic phenylene-1,3-bis-triazole receptors were synthesised with the heterocyclic motif covalently attached to the central phenyl ring through either the carbon or nitrogen. 1H NMR titration experiments reveal that all the receptors bind chloride in d 6-acetone solution with the aryl-substituted systems exhibiting significantly stronger halide association than the alkyl-substituted receptors. Both N-linked systems bind chloride more strongly than their C-linked analogues. Copper(I) and silver(I) cations were also demonstrated to bind to the receptors in solution and in the solid state. Four metal complexes were structurally characterised by X-ray crystallography – in all cases giving interesting polynuclear architectures with a dinuclear silver(I) metallomacrocycle, a trimetallic copper(I) and two tetranuclear silver(I) clusters observed.