Diamondoid and square-grid networks based on bent wheel-and-axle diols

New coordination compounds of general formula Zn(ligand)2X2 (ligand = 2,6-diphenylphenol 4-pyridyl aldimine; X = Cl, Br, and I) have been synthesised and structurally characterized. They are analogous of palladium wheel-and-axle diols (waads), that have high propensity to include small guest molecules into their lattice, but the tetrahedral coordination of zinc ion bends their molecular axle. Here we demonstrate that the tuning of the molecular shape by axle bending enables to achieve a good self-packing efficiency, with loss of the clathrating properties of the material. In particular, Zn(ligand)2X2 waads self assemble to form a fourfold interpenetrated superdiamondoid network with a close-packed structure.