Anion directed assembly of a dinuclear double helicateElectronic supplementary information (ESI) available: Fig. S1: stereoviews showing the packing of 1 in the solid state. Fig. S2: partial 1H NMR spectra of L2 and 1 and their assignment. See http://www.rsc.org/suppdata/cc/b1/b106981k/

The synthesis and structural characterisation of the diamino-bis-pyridine ligand L2 and its diammonium-bispyridinium salt [(H4L2Cl)2].6Cl.H2O 1, are reported; X-ray diffraction studies reveal that chloride coordination causes the latter to adopt a double-helicate structure in the solid-state.