Poly[[tetrachlorido{μ4-tetrakis[(pyridin-4-yl)oxymethyl]methane-κ4N:N':N'':N'''}dizinc(II)] dimethylformamide tetrasolvate]

Acta Crystallogr C. 2013 Jun;69(Pt 6):577-80. doi: 10.1107/S0108270113010937. Epub 2013 May 10.

Abstract

A novel metal-organic framework, {[Zn2Cl4(C25H24N4O4)]·4C3H7NO}n, has been synthesized solvothermally by assembling the semi-rigid tetrahedral ligand tetrakis[(pyridin-4-yl)oxymethyl]methane (tpom) and zinc nitrate in dimethylformamide (DMF). The crystal structure is noncentrosymmetric (P42(1)c). Each Zn(II) cation has a tetrahedral coordination environment (C2 symmetry), which is formed by two chloride ligands and two pyridine N atoms from two tpom ligands. The tetrahedral tetradentate tpom linker has a quaternary C atom located on the crystallographic -4 axis. This linker utilizes all the peripheral pyridine N atoms to connect four Zn(II) cations, thereby forming a wave-like two-dimensional sheet along the c axis. The two-dimensional layer can be topologically simplified as a typical uninodal 4-connected sql/Shubnikov net, which is represented by the Schläfli symbol {4(4),6(2)}. Adjacent layers are further packed into a three-dimensional structure by C-H···Cl hydrogen bonds.