1D → 1D Two-fold parallel interpenetrated coordination polymers with a bis(pyridylurea) ligand

Four unprecedented 1D → 1D interpenetrated (2,4) coordination polymers were obtained from a bis(4-pyridylurea) ligand and octahedral metal ions via catenation of two parallel and collinear 1D ribbons of rings; the ligand L shows an ideal flexibility and adaptability in the formation of these structures.