Crystal structures of two one-dimensional coordination polymers constructed from Mn2+ ions, chelating hexafluoro-acetylacetonate anions, and flexible bipyridyl bridging ligands

Abstract

The syntheses and crystal structures of two one-dimensional coordination polymers, [Mn(C5HO2F6)2(C16H20N2)] n (1) and [Mn(C5HO2F6)2(C20H20N2)] n (2), are described, where C5HO2F6 − is the hexafluoro acetylacetonate anion, C16H20N2 is 1,6-bis(4-pyridyl)-hexane, and C20H20N2 is 1,4-bis[2-(3-pyridyl)ethyl]-benzene. In both phases, the metal ion lies on a crystallographic twofold axis and is coordinated by two chelating C5HO2F6 − anions and two bridging bipyridyl ligands to generate a cis-MnN2O4 octahedron. The bridging ligands, which are completed by crystallographic inversion symmetry in both compounds, connect the metal nodes into zigzag [20 1 ] chains in 1 and contorted [001] chains in 2. Intrachain C–H•••O interactions occur in 1 but not in 2, which may be correlated with the relative orientations of the ligands. Crystal data: 1, C26H22F12MnN2O4, M r = 709.40, monoclinic, C2/c (No. 15), a = 9.3475(2) A, b = 16.6547(3) A, c = 18.3649(4) A, β = 91.1135(8)°, V = 2858.50(10) A3, Z = 4, R(F) = 0.030, w R(F 2) = 0.075. 2, C30H22F12MnN2O4, M r = 757.44, monoclinic, C2/c (No. 15), a = 19.9198(2) A, b = 10.6459(2) A, c = 16.8185(3) A, β = 119.8344(8)°, V = 3093.91(9) A3, Z = 4, R(F) = 0.032, w R(F 2) = 0.078.