Construction of Cu(II) coordination polymers based on semi-rigid tetrahedral pyridine ligands

The assembly of a Cu(II) ion and the semi-rigid tetrahedral pyridine ligand, tetrakis(3-pyridyloxymethylene)methane (L-1), yields three coordination polymers (1-3) by synergy between different solvent mixtures. Single crystal X-ray diffraction analyses reveal that Cu-4(L-1)(OAc)(8) (1) features a two-dimensional sql network, and comprises dimeric five-coordinated Cu-centered square pyramids as the inorganic building units; Cu-2(L-1)(C7H5O2)(4) (2) is also a layered assembly but with a 3,4-connected 3,4L13 net. In this complex, mononuclear CuO2N2 square planar structures and dinuclear CuO3N2 square pyramids both serve as the inorganic building units. Cu(H2O)(2)(L-1)(OAc)(2) (3) is a three-dimensional framework structure based on six-coordinated CuO2N4 square bipyramidal inorganic nodes and tetrahedral semi-rigid pyridine ligands, and dia topology is simplified for 3.