Syntheses and Crystal Structures of Two Zn(Ⅱ) Coordination Polymers Constructed with 4,4’-(Dihydroxymethylene)dibenzoic Acid

Two new isomorphous metal-organic coordination polymers, [Zn(dhmdb)(2,2'- bpy)]n 1 and [Zn(dhmdb)(1,10-phen)]n 2, have been obtained under hydrothermal reactions from 4,4'-(dihydroxymethylene)dibenzoic acid (H2dhmdb), Zn(NO3)2·6H2O and 2,2'-pyridine or 1,10- phenanthroline, respectively. Compounds 1 and 2 have been characterized by FT-IR spectroscopy, thermal analysis and single-crystal X-ray diffraction. The zigzag chains of 1 and 2 are linked into three-dimensional supramolecular networks by both O-H…O hydrogen bonds and π…π stacking interactions. Crystal data for 1: ZnC25H18N2O6, Mr = 507.78, orthorhombic, space group Pbca, a = 14.031(3), b = 10.826(2), c = 27.343(6), V = 4153.5(14)3, Z = 8, Dc = 1.624 g/cm3, F(000) = 2080, μ = 1.231 mm-1, R = 0.0699 and wR = 0.1829. Crystal data for 2: ZnC27H18N2O6, Mr = 531.80, orthorhombic, space group Pbca, a = 13.796(3), b = 10.809(2), c = 28.612(6), V = 4266.8(15)3, Z = 8, Dc = 1.656 g/cm3, F(000) = 2176, μ = 1.203 mm-1, R = 0.0454 and wR = 0.1399.