Three unique MOFs constructed by 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene and dicarboxylates: From rhombic tetrameric zinc(II) 2D layer to 2D + 2D → 3D polycatenated frameworks

Three coordination polymers are reported: compound 1 exhibit a 2D network with rhombic {Zn4} clusters, while 2 and 3 possess a parallel and a inclined 2D → 3D polycatenated framework, respectively.