Coordination polymers and supramolecular solid-state architectures constructed from an organometallic tecton, bis(4-pyridyl)mercury

Abstract

Four new 1-D coordination polymers have been assembled using bis(4-pyridyl)mercury (py2Hg) as spacer: 1∞[Mn(hfac)2(py2Hg)] 1, 1∞[Zn(CH3COO)2(py2Hg)]∙2H2O 2; 1∞[Ni(dipdtp)2(py2Hg)] 3 (dipdtp = O,O′-diisopropyldithiophosphato), 1∞[Zn(H2O)4(py2Hg)]∙(18C6)(ClO4)24 (18C6 = crown ether 1,4,7,10,13,16-hexaoxacyclooctadecane). The crystal structures of 1, 3, and 4 consist of linear chains, while 2 shows a zigzag topology. The zigzag chains in 2 are assembled into supramolecular layers through weak Hg⋯O interactions, and are further linked into a 3-D framework by tetrameric water clusters. The structure of 3 is expanded into 2-D layers through weak Hg⋯S interactions. In crystal 4, the 18C6 molecules act as second coordination sphere ligands. The supramolecular 3-D network is sustained by hydrogen bonds and Hg⋯O interactions. The system [Cu2(valpa)2]∙(py2Hg) 5 was obtained from a co-crystallization process of py2Hg and the binuclear complex [Cu2(valpa)2] (H2valpa is the Schiff base resulted from the condensation reaction between o-vanillin and propanolamine). The py2Hg molecules in 5 interact each other through N⋯Hg bonds generating layers with square meshes. The organometallic tecton, through the mercury atom, is involved in various weak interactions (Hg⋯O, Hg⋯N, Hg⋯S), which play an important role in sustaining the solid state architectures.