Probing copper halide supramolecular arrays of a ditopic ligand with complexes of a monotopic analogue

Abstract

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.