Self-assembled metal–organic squares derived from linear templates as exemplified by a polydentate ligand that provides access to both a polygon and polyhedron

Di- 1a and tetranuclear 1b metal–organic squares have been obtained from bis- and tetra(pyridyl)cyclobutanes synthesized in the solid state, respectively; for 1b, a cyclobutane with two different metal binding subunits supports the formation of a polygon and polyhedron.