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Heterotrinuclear 3d–4f complexes with a naphthalenediol-based acyclic bis(salamo)-type ligand have been synthesized and structurally characterized. Spectral titrations clearly show that the heterotrinuclear complexes [Zn 2 (L)La(OAc) 3 ] ( 1 ), [Zn 2 (L)Ce(OAc) 3 ] ( 2 ) and [Zn 2 (L)Dy(OAc) 3 (CH 3 OH)]·CH 2 Cl 2 ( 3 ) are acquired by the substitution reaction of the obtained homotrinuclear Zn(II) complex with 1 equiv. of Ln(NO 3 ) 3 (Ln 3 + = La 3 + , Ce 3 + and Dy 3 + ). Two Zn(II) ions are penta- and hexa-coordinated with geometries of distorted tetragonal pyramid and octahedron. La(III) ion is deca-coordinated, adopting a distorted bicapped square antiprism geometry. Ce(III) ion is nona-coordinated with geometry of distorted capped square antiprism as well as Dy(III) ion. The different coordination modes of acetate ions in complexes 1 , 2 and 3 lead to different coordination numbers of the lanthanide(III) ions. Furthermore, the structures and fluorescence properties have been discussed. [ABSTRACT FROM AUTHOR]

Abstract: Mononuclear and trinuclear Cu(II) complexes with chemical formula [CuL]·CH3OH (1) and [{(Cu(μ-L))2(OAc)2}Cu] (2), where H2L=2,2′-[1,1′-(ethylenedioxydinitrilo)diethylidyne]diphenol, have been synthesized and characterized by elemental analyses, 1H NMR, IR and UV–vis spectra et al. Crystallographic data of complex 1 reveal the formation of an asymmetric mononuclear structure and a slight distortion toward tetrahedral geometry from the square planar structure, in which the introduction of the non-coordinated methanol molecule lead to the assembly of the 1D chains by hydrogen bonding, Cu⋯π and π⋯π interactions. Complex 2 have the elongated square pyramidal geometries for the two terminal Cu(II) ions and an octahedral coordinated geometry for the central Cu(II) ion. In complex 2, two acetate ions coordinate to three Cu(II) ions adopting a familiar syn–syn (μM-O-C-O-M) coordinated fashion. The central Cu(II) ion sits in a crystallographic inversion centre. Therefore, the whole molecule of complex 2 is rigorously centrosymmetric, and forms a 3D supramolecular networks through intermolecular C–H⋯O and C–H⋯π interactions. [Copyright &y& Elsevier]

Abstract: Two solvent-induced trinuclear nickel(II) clusters, [{NiL(CH3OH)}2(OAc)2Ni]·2CH3OH (I) and [{NiL(C2H5OH)}2(OAc)2Ni]·2C2H5OH (II), have been synthesized by the reaction of a new Salen-type bisoxime chelating ligand of 5,5′-di(N,N′-diethylamino)-2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol (H2L) with nickel(II) acetate tetrahydrate in different solvents. Clusters I and II were characterized by elemental analyses, IR spectra, UV–vis absorption spectra, TG–DTA and X-ray diffraction methods. In clusters I (or II), there are two ligand moieties (which provide N2O2 donors), two acetate ions, two coordinated methanol (or ethanol) molecules and two crystallizing methanol (or ethanol) molecules, which result in the formation of three slightly distorted octahedral geometries around Ni(II) ions. Interestingly, nickel(II) ions in the structures of clusters I and II are all six-coordinated geometry, but clusters I and II are grown up in different solvent. Right because of this, solvent effect cause to their different crystal structures. [Copyright &y& Elsevier]

Abstract: A tri-nuclear cobalt(II) cluster, [(CoL)2(OAc)2Co]·2C2H5OH, has been synthesized by the reaction of cobalt(II) acetate tetrahydrate with a novel Salen-type bisoxime chelating ligand, 3,3′-dimethoxy-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol (H2L), and characterized by elemental analyses, IR spectra, TG-DTA and molar conductances. UV–vis spectroscopic titration in methanol solution clearly indicated the exclusive formation of the 3:2 [Co3L2]2+ cluster. The single-crystal X-ray diffraction determination of the Co(II) cluster shows that there are two acetate ions coordinate to three cobalt(II) ions through Co–O–C–O–Co bridges, and quadruple μ-phenoxo oxygen atoms from two [CoL] chelates also coordinate to cobalt(II) ions. Interestingly, different conformational central ions: five- and six-coordinated geometries were found in the cluster. [Copyright &y& Elsevier]

Four novel butterfly-shaped hetero-pentanuclear 3d–4f complexes [Zn 4 (L) 2 Sm(H 2 O) 4 ]3NO 3 ·2EtOH ( 1 ) [Zn 4 (L) 2 Eu(NO 3 ) 2 (MeOH)(EtOH)]NO 3 ·H 2 O ( 2 ), [Zn 4 (L) 2 Gd(H 2 O) 4 ]3NO 3 ·MeOH·EtOH ( 3 ) and [Zn 4 (L) 2 Tb(NO 3 )(EtOH)(H 2 O) 2 ]NO 3 ·MeOH·EtOH ( 4 ) were synthesized by the reactions of a bis(salamo)-type tetraoxime ligand (H 4 L) with Zn(OAc) 2 ·2H 2 O and Ln(NO 3 ) 3 ·6H 2 O (Ln = Sm, Eu, Gd and Tb), respectively. The structures of complexes 1 – 4 were fully characterized by elemental analyses, FT–IR, UV–Vis spectroscopy and single crystal X-ray crystallography, and their luminescence properties were also discussed. In addition, cyclic voltammograms were used to characterize electrochemical properties of the Zn(II)–Ln(III) (Ln = Sm, Eu, Gd and Tb) complexes. [ABSTRACT FROM AUTHOR]

wo unusual Cu(II) complexes [{Cu(L 1 )} 2 ] (1) and [Cu 2 (L 2 )] (2), with an asymmetric salamo-type bisoxime ligand H 2 L 1 were synthesized and characterized by elemental analyses, UV–Vis, fluorescent spectra, Hirshfeld surface analyses and single-crystal X-ray diffraction analyses. For the complex 1 , two Cu(II) ions are penta-coordinate by N 2 O 2 donor atoms from the (L 1 ) 2− unit and one bridged phenol oxygen atom from another (L 1 ) 2− unit. Complex 1 does not have intermolecular hydrogen bonds, formed an isolated zero dimensional structure. Meanwhile, for the complex 2 , an unexpected ligand H 4 L 2 was synthesized by aldol condensation reaction of H 2 L 1 and acetone upon coordination, then the new ligand and Cu(II) ions combined, formed a highly symmetrical structure, and two Cu(II) ions of the complex 2 have tetra-coordinate environment. With the help of intermolecular hydrogen bonding C H⋯O interactions, a self-assembled infinite 1D supramolecular structure was formed. Meanwhile, the photophysical spectra and Hirshfeld surface analyses of the complexes 1 and 2 were also measured and discussed. [ABSTRACT FROM AUTHOR]

Four homo/heterometallic complexes [Cu 3 (L)( μ 2 -OAc) 9 (CH 3 OH) 9 ]·3CHCl 3 (1), [Cu 2 (L)Ca( μ 2 -NO 3 ) 9 ] (9), [{Cu 2 (L)Sr( μ 2 -NO 3 ) 9 } 9 ]·CH 3 CH 2 OH (11) and [Cu 2 (L)Ba( μ 2 -OAc) 9 (OAc)] (14), containing an acyclic naphthalenediol-based ligand H 4 L, were synthesized and characterized by elemental analyses, IR, UV–Vis, fluorescence spectra, TG-DTA and X-ray crystallography. The complex 1 was obtained by the reaction of H 4 L with 11 equivalents of Cu(OAc) 9 ·2H 2 O. The heterometallic complexes 9, 11, 14 were acquired by the reaction of H 4 L with 9 equivalents of Cu(OAc) 9 ·2H 2 O or Cu(NO 3 ) 9 ·2H 2 O and 1 equivalent of M(OAc) 9 (M = Ca, Sr and Ba). Owing to the different coordination cavities of the N 2 O 2 and O 6 of the completely deprotonated (L) 14- unit, the crystal structures showed the N 2 O 2 sites were occupied by Cu(II) atoms, alkaline earth metal(II) atoms occupied the O 6 site of the ligand (L) 14- unit, respectively. Furthermore, the fluorescence properties and TG-DTA analyses were discussed. [ABSTRACT FROM AUTHOR]

The optical properties of a novel chemosensor for cyanide anions based on a symmetric bis(salamo)-type ligand (H 3 L) were investigated by UV–Vis and fluorescence spectroscopy in MeOH/H 2 O (1:1 v/v) solution. Sensor H 3 L can selectively sense CN − based on prominent color changes among other anions. The chemosensor exhibits an apparent fluorescence enhancement at 482 nm to CN − which because cyanide ions interact with C N bonds. Combining the corrected Benesi-Hildebrand formula, the binding constant of the formed host-guest complex was calculated as 2.42 × 10 5 M − 1 . Meanwhile, the detection limit of the sensor toward CN − was 8.91 × 10 − 7 M. It is worth noting that the designed sensor can be used for rapid detection of cyanide anions in basic pH range, and has great practical value. [ABSTRACT FROM AUTHOR]