| Using Krohnke procedure, two tridentate ligands, 4'-phenyl-2,2':6',2" -terpyridine (PTPY) and 4'-(p-toluyl)-2,2':6',2"-terpyridine (MPTPY) were prepared, from which zinc and cupric complexes, [ZnⅡ(PTPY)2](ClO4)2 (1), [ZnⅡ(MPTPY)2] (ClO4)2 (2), [ZnⅡ(PTPY)Cl2]2 · 2H2O (3), [CuⅡ(PTPY)2](ClO4)2 (4), [CuⅡ(MPTPY)2] (ClO4)2 (5), [CuⅡ(PTPY)(H2O)](ClO4)2 · 2H2O (6), [ZnⅡ(PTPY)(tp) (H2O)]n (8), [Cu(PTPY)(tp)(H2tp)]n (9) were synthesized. As an analogue of the oligopyridine complexes, metallopolymer, [Zn(phen)(tp)(H2O)]n (7) was obtained. All of these complexes were characterized with IR, UV-vis and fluorescent spectra and structurally defined by X-ray crystal diffraction.Crystal structure analyses of PTPY and MPTPY and their complexes 1 -6, 8-9 reveal that in solid state, the terpyridine moieties in both ligands are approximately coplanar and three pyridine rings are arranged in a transoid form. Metallation induces a rotation of terminal Py rings about the interannular carbon-carbon bonds.All the bis-terpyridine chelating mononuclear complexes, such as (1), (2), (4), (5), involve a central metal ion having a N6 coordination sphere provided by the terpyridine ligands. MⅡ-Nt bonds are systematically longer than MⅡ-Nm owing to the intra-ligand stress.In the mononuclear zinc complexes, [Zn(PTPY)2](ClO4)2 ( 1 ) and [Zn(MPTPY)2](ClO4)2 ( 2 ), weak hydrogen bonding interaction, C-H...O bond was found among the counter ions ClO4 and pyridyl protons. Through the non-classical bonding, the complexes assemble into supramolecules. The mononuclear cupric complexes, [Cu(PTPY)2](ClO4)2 ( 4 ) and [Cu(MPTPY)2](ClO4)2 ( 5 ) have analogical hydrogen bonding interactions.Interestingly, complex [Zn"(PTPY)Cl2]2 * 2H2O (3) consists of two asymmetrically coordination entities and two water molecules. In each coordination entity, Zn2+ has N3C12 coordination environment, that is that Zn2+ is coordinated by two chloride ions and three N from PTPY using sp3d hybridizing mode. Two independent entities are somewhat different, one is a regular square pyramid (t=0.073), another is a distorted square pyramid (1=0.223 ). What's more, two entities have different hydrogen bonding environment, one forms C—H---C1 hydrogen bonds between coordinated chloride ion and py ring from another entity, the other forms O—H"'C1 hydrogen bonds between coordinated chloride ion and water.[Cu(PTPY)(H2O)](ClO4)2 * 2H2O (6) is a mononuclear complex of copper. Cu2+ has a N3O coordination environment, that is, Cu2+ is coordinated by three N from PTPY and a water O atom, using dsp2 hybridizing mode. The whole structure is a planar quadrangle.Complex [Zn(phen)(tp)(H2O)]n (7) is a 1-D zig-zag chain-like polymer. Each Zn2+ has a N2O3 coordination environment., that is, Zn2+ is coordinated by two N from phen, two O from different tps, and one water O, using sp3d hybridizing mode. The configuration is a highly distorted trigonal-bipyramid. Each tp2" connects two Zn2+ utilizing u2 -bridging mode (bis-monodentate mode). And each Zn2+ bridges two tp2* too. As a result, a --Zn—TPT—Zn—TPT"- 1-D zig-zag chain is formed. Phen is a terminal ligand, which saturates five-coordinated structure of Zn2+ together with water. Distance of bridged Zn--Zn is 11.281 A.Complex [Zn(PTPY)(tp)(H2O)]n (8) is a 1-D ribbon polymer. Each Zn2+ is coordinated by carboxylic O atoms of two tp2" and three N from PTPY, utilizing sp3d hybridizing mode. Zn2+ coordination structure is trigonal-bipyramid. The thereinto hidden 1-D chain is formed in the same fashion as (7). PTPY is a terminal ligand, which saturates five-coordinated structure of Zn2+. Distance of bridged ZrvZn is 11.019 A. It's interesting that free water exists in the crystal, which forms hydrogen bond with adjacent tp2'. So, partially closed ring is formed, which finally results in a 1-D ribbon infinite structure.Complex [Cu(PTPY)(tp) ? (H2tp)]n (9) is a 2-D planar polymer. Each Cu2+ has a N3O2 coordination environment, that is, Cu2+ is coordinated by two carboxylic O from different tp2' and three N from PTPY, utilizing sp3d hybridizing mode. The coordination structure of Cu2+ is a distorted quartpyramid. The thereinto hidden 1-D chain is formed in the same fashion as (8). PTPY is a terminal ligand, which saturates five-coordinated structure of Cu2+. Distance of bridged Cu---Cu is 11 285 A. Interestingly free I-typ exists in the crystal, which forms hydrogen bond with coordinated tp2". So, each thereinto hidden 1-D chains are binded through fbtp, and 2-D planar polymer is finally formed. To our knowledge, hydrogen bonds formed by free H2tp is rarely found in crystal, so the structure is significant.UV-vis spectrum of soluble complex is investigated, we found that substituted group of TPY has palpable effects on the spectral properties . Fluorescent spectrum is also investigated, all the five zinc complexes exhibit strong fluorescent properties.
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