A novel one-dimensional zinc coordination polymer containing 4-methylbenzoate and 4,4-bipyridine

Acta Crystallogr C. 2008 Aug;64(Pt 8):m271-3. doi: 10.1107/S0108270108018441. Epub 2008 Jul 5.

Abstract

The title compound, catena-poly[[tris(mu-4-methylbenzoato)-kappa(2)O:O;kappa(4)O:O'-(4-methylbenzoato-kappa(2)O,O')dizinc(II)]-mu-4,4'-bipyridine-kappa(2)N:N'], [Zn(2)(C(8)H(7)O(2))(4)(C(10)H(8)N(2))](n), is a novel coordination polymer. The asymmetric unit contains two unique Zn(II) ions, four 4-methylbenzoate ligands and one 4,4'-bipyridine (4,4'-bpy) ligand, all in general positions. The four 4-methylbenzoate ligands link the two Zn(II) centres to form a dinuclear unit, with a Zn...Zn separation of 3.188 (2) A, which can be regarded as a supramolecular secondary building unit (SBU). These SBUs are further bridged by 4,4'-bpy ligands, forming a novel one-dimensional infinite chain. There are pi-pi stacking interactions between the benzene rings of the 4-methylbenzoate ligands and the pyridyl rings of the 4,4'-bpy ligands, leading to the formation of a corrugated layer. These layers are further assembled via C-H...O hydrogen bonds into a three-dimensional supramolecular network structure. Coordination polymers such as the title compound are of interest for their potential applications as functional materials.