The use of H-bonding to increase the dimensionality of coordination networks of Cu(I) and Cu(II)

Two two-dimensional coordination networks were prepared by the reaction of a bent bridging ligand, bis(4-pyridyl)amine (bpa), with CuI and CuCl₂. Both networks were formed by bpa ligands bridging between Cu₂I₂ dimers or six-coordinate trans CuCl₂ moieties. The networks were isotopological and displayed (4, 4) topology with nodes based on the midpoint of the Cu₂I₂ dimer or the Cu(II) ion, respectively. Reaction of a monoprotonated bpa ligand with CuSO₄ resulted in the formation of a neutral discrete complex. H-bonding networks were formed in all three cases. The two coordination polymers were both extended to give related three-dimensional networks with the resulting CuI H-bonded network displaying twofold interpenetration. The discrete neutral complex formed a two-dimensional H-bonded network and when further H-bonding to H₂O solvent molecules was considered, a highly complex three-dimensional network resulted with five different nodes of four different connectivities.