Novel tin supramolecular compounds and coordination polymers: Influence of aromatic dicarboxylates on the crystal structures

Abstract

Six tin based coordination compounds containing pyridine-2,5-dicarboxylate (pydc), terephthalate (ta), or naphthalene-2,6-dicarboxylate (ndc) ligands have been synthesized hydro-/solvo-thermally and characterized by single crystal X-ray diffraction. Compounds 1 and 2 are polymorphs with chemical composition of Sn(Hpydc) 2 and have strikingly different 1D supramolecular structures due to the different linking mode of the monoprotonated pydc ligand. Compound 1, the major phase, crystallizes in the space group P2 1/ n ( a = 16.4038(8) Å, b = 48.092(2) Å, c = 19.0217(9) Å, β = 90.066(1)°) and compound 2, the minor phase, crystallizes in the space group P2 1/ n ( a = 9.680(3) Å, b = 12.793(4) Å, c = 12.591(4) Å, β = 108.703(7)°). Compound 3, Sn(pydc)(DMF), crystallizes in the space group P2 1/ c ( a = 11.4932(6) Å, b = 8.4885(5) Å, c = 12.0493(6) Å, β = 100.568(1)°,) with infinite 1D helical chains extended along the crystallographic b-axis. Compound 4, Sn 2(O)(pydc), crystallizes in the space group C2/ c ( a = 13.5948(14) Å, b = 6.6759(7) Å, c = 20.200(2) Å, β = 90.007(2)°), and is a 3D coordination polymer that contains edge-shared Sn 4O 2 clusters arranged into 1D stair-like structures that are stacked to form small channels. Compound 5, Sn 3(O)(ta) 2, which crystallizes in the space group P ‾1 ( a = 6.9436(6) Å, b = 7.1505(6) Å, c = 19.1353(16) Å, α = 83.714(1)°, β = 89.686(1)°, γ = 64.034(1)°) and compound 6, Sn 3(O)(ndc) 2, which crystallizes in the space group P ‾1 ( a = 7.0892(10) Å, b = 7.2714(10) Å, c = 23.400(3) Å, α = 86.699(2)°, β = 85.914(2)°, γ = 63.423(2)°), are structurally related and form tin oxide layers consisting of bridged Sn 3O clusters, that are connected to adjacent layers by the ta and ndc ligands, respectively.