Synthesis, crystal structures, and photoluminescence of a series of coordination polymers with two homologous functional flexible ligands

摘要

Two functional, flexible ligands, namely 3,6-dipyrazolyl-9-ethylcarbazole (L-1) and 3,6-diimidazolyl-9-ethylcarbazole (L-2) have been synthesized and characterized and their coordination to various Ag-I, Cd-II, and Co-II salts investigated. Six new complexes, 1-6, have been obtained and fully characterized by IR spectroscopy, elemental analysis, and single-crystal X-ray diffraction. The 2D double helix framework of the complex [(CdLI2)-I-1](n) (1) is formed by C-H center dot center dot center dot I hydrogen bonds, whereas the same 2D double helix framework of compound [{(AgLSO3PhCH3)-S-1}(2)(CH3OH)(H2O)](n) (2) is formed by S-O center dot center dot center dot H and C-H center dot center dot center dot O hydrogen bonds and weak pi-pi interactions. The coordination modes of Cd-II and Con in [CdL22(NCS)(2)](n) (3), [CoL22(NCS)(2)(CHCl3)(2)](n) (4), [CdL22(NO3)(2)(CH3OH)(2)](n) (5), and [CoL22(NO3)(2)(CH3OH)(2)](n) (6) are the same, but in the packing diagram interlayers form a 3D network through C-H center dot center dot center dot S interactions and pi-pi interactions in 3, interlayers form a 3D network through S center dot center dot center dot S interactions and pi-pi interactions in 4, novel 3D structures are formed by interchain O center dot center dot center dot H-C hydrogen bonding and interlayer O center dot center dot center dot H-C hydrogen-bonding and pi-pi interactions in 5 and 6. The structural differences between these complexes show the influence of the orientation of the coordinating group of the ligand. These results also show that the metal ion, anion, and nonbonding and pi-pi interactions are significant factors in controlling the structural topology of these metal-organic supramolecular architectures. In addition, the luminescence properties of L-1, 1, L-2 and 3 are investigated in the solid state at room temperature. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007).