Probing copper halide supramolecular arrays of a ditopic ligand with complexes of a monotopic analogueDedicated to Barbara Duncan on the occasion of her retirement as Senior Teaching Fellow in Chemistry at the University of Otago, in acknowledgement of her contribution to our research activities

The ligand bis(2-pyridylmethyl)sulfide L′ and the complexes it formed were used as simple probes for the complexes of 2,5-bis(2-pyridylmethylsufanylmethyl)pyrazine L. L′ and L were reacted in 1 ∶ 1 and 1 ∶ 2 molar ratios, respectively, with both CuCl2 and CuI. Crystal structures of all four complexes were determined, CuCl2L′·H2O (1), Cu2Cl4L (2), Cu2I2L′2 (3) and [Cu2I2L]∞ (4). The Cu(II) ions in 1 and 2 were square pyramidal. For 2 crystal structures of the anti (2a) and the syn (2b) isomers were determined and both were found to form proto-polymeric chains. Complex 3 was dimeric and contained Cu2I2 bridges. The structure of 4 revealed one-dimensional polymeric chains in which the ligands were joined by Cu2I2 bridges. This work demonstrated the successful use of the complexes of L′ as probes for 4 and to a lesser extent for 2a and 2b.