Three Silver(I) Coordination Polymers Based on Pyridyl Ligands and Auxiliary Carboxylic Ligands: Luminescence and Efficient Sensing Properties.

Easily producible sensors for harmful industrial waste compounds are of significant interest for both human health and the environment. Three novel coordination polymers, [Ag(µ-aca)(µ4-bztpy)1/2] (1), [Ag(µ-bza)(µ-bpa)] (2), and [Ag2(µ-aca)2(µ-bpa)2]·EtOH·2H2O (3), were assembled in this study by reactions using Ag+ as a node with the pyridyl ligand 1,2,4,5-tetrakis(4-pyridyl)benzene (bztpy) or 9,10-bis(4-pyridyl)anthracene (bpa) and an auxiliary chelating carboxylic ligand. Single-crystal X-ray structural analyses revealed that compound 1 has a 3D framework consisting of 1D [Ag(aca)]∞ chains and bztpy linkers, while 2 and 3 have 2D layered structures consisting of binuclear Ag-carboxylate units and bpa linkers, respectively. Topological studies revealed that 1 has a bbf topology, while 2 and 3 are 2D [4,4] rhombic grids. The compounds were further characterized by powder X-ray diffraction, IR, elemental analysis, thermogravimetric analysis, and a luminescence study. The solids of 1-3 exhibited intense photoluminescent emission with λemmax at ca. 493, 472, and 500 nm, respectively. Remarkably, due to their excellent framework stability, 1 and 2 can act as multiresponsive luminescent sensors for nitrobenzene, Fe3+, and Cr2O72- with a high selectivity and sensitivity ascribed to their quenching effect.

Syntheses, crystal structures, weak interaction, magnetic and photoluminescent properties of two new organic-inorganic molecular solids with disubstituted benzyl triphenylphosphinium and tetra(isothiocyanate)cobalt(II) anion.

Two new organic-inorganic molecular solids of tetra(isothiocyanate)cobalt(II) dianion and disubstituted benzyl triphenylphosphinium, [2Cl4FBzTPP]2[Co(NCS)4] (1) and [2Cl4ClBzTPP]2[Co(NCS)4] (2) ([2Cl4FBzTPP](+)=1-(2'-chloro-4'-fluorobenzyltriphenylphosphonium) and [2Cl4ClBzTPP](+)=1-(2',4'-dichlorobenzyltriphenylphosphonium), were synthesized and characterized by elemental analysis, FT-IR, UV-Vis spectra, ESI-MS and single crystal X-ray diffraction method. Compounds 1 and 2 crystallize in the monoclinic Pc and triclinic P-1, respectively. The Co(II) ion of the [Co(NCS)4](2-) anion shows a distorted tetrahedral coordination geometry. The [2Cl4FBzTPP](+) cations containing P(2) atoms in 1 form a column by the Cl⋯π interactions, while the [2Cl4ClBzTPP](+) cations in 2 form two columns by the C-H⋯π and π⋯π interactions. The anion and the cation are linked by C-H⋯S hydrogen bonds and Cl⋯S interactions. Magnetic susceptibility measurement in the temperature range 2-300K shows that both 1 and 2 exhibit a weak antiferromagnetic exchange interaction as the temperature falls, and ultraviolet fluorescence emission in the solid state at room temperature.

Syntheses, crystal structures, luminescent and magnetic properties of two molecular solids containing naphthylmethylene triphenylphosphinium cations and tetra(isothiocyanate)cobalt(II) dianion.

The reaction of CoCl2 with the naphthalene methylated triphenylphosphinium bromide [n-NAPMeTPP]Br (n=1, 2) and KSCN, in a methanolic medium at ambient temperature, leads to the self-assembly formation of hybrid 2:1 organic-inorganic molecular solids, [1-NAPMeTPP]2[Co(NCS)4](1) and [2-NAPMeTPP]2[Co(NCS)4](2) ([NAPMeTPP](+)=(naphthylmethylene)(triphenyl)phosphinium), which have been characterized by elemental analyses, IR spectroscopy, UV-Vis spectra, ESI-MS, molar conductivity and single-crystal X-ray diffraction structural analyses. Compound 1 crystallizes in the orthorhombic space group Pna21, while 2 does in the monoclinic space group C2/c. The cations form a dimer through the weak intermolecular C-H⋯π interactions in 1 and π⋯π interaction in 2, while the anion and cation are linked by the C-H⋯S hydrogen bond in 1. Two molecular solids show dual functionalities: (1) the broad fluorescence emission around 400nm in the solid state at room temperature; (2) the weak antiferromagnetic coupling behavior.

[Synthesis and spectral properties of tailed sercine tetraphenylporphyrin cobalt complex].

A new tailed sercine tetraphenylporphinatozinc, 5-(p-butoxyphenyl-10,15,20-trichlorophenyl)porphine and cobalt complex (Co[Ser-TPP]) was synthesized and characterized by elementary analysis, UV, IR, 1HNMR and Raman spectra. The electronic absorption spectra of axial coordination reactions of Co[Ser-TPP] with pyridine, 4-methylpyridine, 4-aminopyridine, 4,4-bipyridine, imidazole, 1-methylimidazole and 2-methylimidazole were inverstigated. The results showed that the changes of electronic absorption spectra of Co[Ser-TPP] could be attributed to the axial coordination reactions of Co[Ser-TPP] with pyridine and imidazole series.