Unusual Very Strong O–H···O Hydrogen Bonding in Zinc Complex: Crystal Structure and Photoluminescence of [Zn(HL)(bpy)2(H2O)]2(L) (L = O2C(CF2)6CO2, bpy = 2,2′bipyridine)

Abstract

The centrosymmetric dimer zinc compound, [Zn(HL)(bpy)2(H2O)]2(L), (L = O2C(CF2)6CO2, bpy = 2,2′-bipyridine), was obtained through the reaction of Zn(ClO4)2·6H2O, bpy and perfluorosuberic acid. Zn(II) centre is coordinated by four N atoms from two bpy ligands and two O atoms from a water molecule and monoanionic suberate ligand in a distorted octahedral coordination environment. The unit structure contains crystallographically centrosymmetric suberate anion which acts as a bidentate bridging ligand between each cationic monomer complex unit via hydrogen bonding. The very strong interaction of hydrogen bonding of hydoxycarbonyl–carboxylate system in solid state has O–H···O 2.436(3) A (O···H = 1.25(6) A and H···O = 1.19(6) A). These units are also connected to each other via π···π, C–H···π, C–F···π and F···F stacking interactions, C–H···O, O–H···O and C–H···F hydrogen bonds giving rise to a multi-dimensional network. The complex is the first reported example of a coordination compound based on both bpy ligands together with perfluorosuberic acid. Moreover, compound exhibit intense solid state fluorescent emissions at room temperature. The synthesis and X-ray characterization of unusual centrosymmetric dimer zinc compound, [Zn(HL)(bpy)2(H2O)]2(L) (L = O2C(CF2)6CO2, bpy = 2,2′bipyridine), and its photoluminescence property have been reported. The very strong interaction of hydrogen bonding of hydroxycarbonyl-carboxylate system in solid state has O–H···O 2.436(4) A (O···H = 1.25 (7) A, H···O = 1.20(7) A and OHO = 168.4°).