Water helicate (H2O)5 hosted by a novel 2D CoII-coordination framework with left- and right-handed helical units

A novel 2D cobalt(II) coordination polymer comprising left- and right-handed helical chains, {[H(2)bpp] [CO2(bPP)(2)(Hbtec)(2)(H2O)(4)]center dot(H2O)(5)}(n) (1) (bpp=1,3-bis(4-pyridyl)-propane and H(4)btec=1.2,4,5-benzenetetracarboxylate), was prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction method. Complex 1 provides suitable hydrophilic channel in which lattice water molecules accumulate, forming a (H2O)(5) helicate, stabilized by anchoring to the host structure through hydrogen-bonding interactions involving alternating water molecules and the carboxylate oxygen atoms of Hbtec(3-) ligands. (C) 2012 Elsevier B.V. All rights reserved.