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Two new mercury(II) complexes [Hg(TDMPT)Cl2] (1) and [Hg37(TDMPT)12Br74] (2) (TDMPT = 2,4,6-tris(3,5-dimethylpyrazolyl)-1,3,5-triazine) have been prepared and characterized by X-ray structural analysis. Mercury(II) complex 1 is a mononuclear coordination compound. Meanwhile, mercury(II) complex 2 is the first example of the 3D coordination polymer with a 1D inorganic chain based on the Lindqvist-type [Hg6Br19]7− anion as building blocks. Furthermore, the bromide anions act as terminal, μ2- and μ6-bridge ligands.

A new fluorescent chemosensor 5-( p - N , N ′-bis(2-pyridyl)amino)phenyl-10,15,20-tris( p -methoxyphenyl)porphyrin zinc has been designed and synthesized by the Ullmann-type coupling. It displays high selectivity for Cu 2+ ion and exhibits fluorescence quenching upon binding of Cu 2+ ion with an “on–off” type fluoroionophoric switching property, and its fluorescence can be revived by addition of EDTA disodium solution.

Four new complexes [Zn(H2biim)2(H2O)2](Hbdc)2·(H2biim)·2H2O (1), [Zn(H2biim)2(H2O)](bdc)·CH3OH (2), [Co(H2biim)2(H2O)2](Hbtc)·4H2O (3) and [Cd(H2biim)2(H2O)(bdc)]·H2O (4) (where H2biim = 2,2′-biimidazole, bdc = 1,3-benzenedicarboxylate and btc = 1,3,5-benzenetricarboxylate) have been synthesized and characterized by single-crystal X-ray diffraction. The [M(H2biim)2(H2O) n ]2+ building blocks are assembled with carboxylates via charge-assisted N–H···O and O–H···N hydrogen bonds (N···O = 2.607 ∼ 2.926 A, ∠N–H–O = 151 ∼ 176°) into 1-D ribbons (1–3) and 3-D network (4). The ribbons are further arranged into 3-D networks via hydrogen bonds between carboxylate and water molecules as well as the free H2biim molecule (1) or methanol molecule (2). In complex 2, the CH3OH molecules are clathrated in the cavities. The results show that three robust heteromeric hydrogen-bonded synthons, namely and can be exploited to assemble the [M(H2biim)2(H2O) n ]2+ (M = Cd, Co and Zn, n = 1, 2) building blocks with dicarboxylates...

The new complex [Cd2(bpa)2Cl4]·6 H2O [bpa = N,N'-bis(picolinamide)azine] has been synthesized in which each bpa ligand is twisted into a spiral-like conformation and the two CdII ions are ligated by two bpa ligands to form a double-stranded binuclear helicate. Unprecedented water chains featuring cyclic water tetramers composed of three independent water molecules are trapped by [Cd2(bpa)2Cl4] double helicates by hydrogen bonds. The binuclear chiral helicates are interlinked into homochiral layers by hydrogen bonds with the water tapes. The layers are alternately stacked in a heterochiral fashion to yield the final racemic structure. The complex shows an endotherm at 65.7 °C in the DSC due to loss of water molecules, giving an enthalpy value of 47 kJ mol–1 per water molecule. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

Three new complexes of [Co(H2biim)2(1,2-bdc)] (1), [Cd(H2biim)(1,3-bdc)]2 (2), and [Cd3(H2biim)2(1,4-bdc)3]·2H2O (3) (bdc = benzenedicarboxylate, H2biim = 2,2‘-biimidazole) have been synthesized and characterized by single-crystal X-ray diffraction. Complex 1 exhibits a 2-D herringbone architecture with mononuclear building blocks assembled via a robust hydrogen-bonded synthon R22(9). The homo- and heterochiral assemblies were observed in 1 between the H2biim ligand and carboxylate group via single and double hydrogen-bonded synthons R22(9). Complex 2 is a ribbonlike polymer based on a binuclear unit, and the ribbons are alternately decorated by H2biim ligands on both sides and further packed through intercalation of the lateral H2biim ligands and hydrogen bonds between the H2biim and carboxylate oxygen atoms into 2-D networks. These layers extend into a 3-D architecture via π−π stacking interactions. Complex 3 is a 3-D coordination polymer with a α-Po net topology based on linear trinuclear {Cd3O14N4} cl...

A new copper(II) fluorescent sensor 5,10,15,20-tetra((p-N,N-bis(2-pyridyl)amino)phenyl)porphyrin zinc (1) has been designed and synthesized by the Ullmann-type condensation of bromoporphyrin zinc with 2,2'-dipyridylamine (dpa) under copper powder as a catalyst as well as with K2CO3 as the base in a DMF solution. It consists of two separately functional moieties: the zinc porphyrin performs as a fluorophore, and the dpa-linked-to-zinc porphyrin acts as a selected binding site for metal ions. It displays a high selectivity and antidisturbance for the Cu2+ ion among the metal ions examined (Na+, Mg2+, Cr3+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Ag+, Zn2+, Cd2+, Hg2+, and Fe3+) and exhibits fluorescence quenching upon the binding of the Cu2+ ion with an "on-off"-type fluoroionophoric switching property. The detection limit is found to be 3.3 x 10(-7) M (3s blank) for Cu2+ ion in methanol solution, and its fluorescence can be revived by the addition of EDTA disodium solution. The design strategy and remarkable photophysical properties of sensor 1 help to extend the development of fluorescent sensors for metal ions.

Two new isostructural complexes [M(H2biim)3][M(btc)(Hbiim)].2H2O (M = Co, (1); M = Ni, (2)) (btc = 1,3,5-benzenetricarboxylate; H2biim = 2,2'-biimidazole) have been synthesized and characterized by single-crystal X-ray diffraction. They present a unique structure consisting of two distinct units: the monomeric cations [M(H2biim)3]2+ and the two-dimensional (2D) anionic polymer [M(Hbiim)(btc)]2-. In the anionic moiety, the Hbiim- monoanion is simultaneously coordinated to one metal atom in a bidentate mode and further to another metal atom in a monodentate mode. The imidazolate groups bridge the two adjacent metal ions into a helical chain which is further arranged in left- and right-handed manners. These chains are bridged by btc ligands into a 2D brick wall structure. The most interesting aspect is that the [M(H2biim)3]2+ cations act as pillars and link the anionic layers via robust heteromeric hydrogen-bonded synthons (9) and (7) formed by the uncoordinated oxygen atoms of carboxylate groups and the H2biim ligands, resulting in a microporous metal-organic framework with one-dimensional (1D) channels (ca. 11.85 angstroms x 11.85 angstroms for 1 and 11.43 angstroms x 11.43 angstroms for 2). Magnetic properties of these two complexes have also been studied in the temperature range of 2-300 K, and their magnetic susceptibilities obey the Curie-Weiss law in the temperature range of 20-300 K (for 1) and 2-300 K (for 2), respectively, showing anti-ferromagnetic coupling through imidazolate bridging. Taking into consideration the Heisenberg infinite chain model as well as the possibility of chain-to-chain and chain-to-cation interactions, the anti-ferromagnetic exchange of 2 is analyzed via a correction for the molecular field, giving the values of g(cat) = 2.296, g(Ni) = 2.564, J = -13.30 cm(-1), and zJ' = -0.017 cm(-1). The microporous frameworks are stable at ca. 350 degrees C. They do not collapse after removal of the guest water molecules in the channels, and they adsorb methanol molecules selectively.