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Centrosymmetric homopolynuclear Cu(II) and Co(II) chelated complexes, [Cu2(L)(H2O)2] (1) and [Co4(L)(μ-OAc)2(CH3OH)4(OAC)2]⋅2CH2Cl2 (2), were synthesized using a new symmetrical methoxy-disubstituted bis(salamo)-type ligand, H4L, with Cu(II) and Co(II) salts in organic solvents. Complexes 1 and 2 were structurally characterized by single-crystal X-ray crystallography. The results indicated that 1 is a five-coordinate dinuclear structure containing Cu(II) and 2 is a tetranuclear Co(II) complex with two distinct six-coordinate environments. Furthermore, 1 and 2 pack into three-dimensional and two-dimensional extended networks, respectively. The UV–Vis spectra, IR spectra, and Hirshfeld surface analyses of the complexes were carried out to further characterize the coordination between H4L and the metal(II) ions. Fluorescence methods were used to interrogate the coordination, where changes in emission with varied amounts of ligand supported solution-phase coordination ratios of H4L with Cu(II) ion of 1:2 and with Co(II) ion of 1:4, respectively. [ABSTRACT FROM AUTHOR]

A penta-coordinated dinuclear Zn(II) complex, [Zn2(L)(μ-PhCOO)(EtOH)] (1), and a hexa-coordinate tetranuclear Cd(II) complex, [{Cd2(L)(EtOH)(η-OAc)}2]·2CH2Cl2 (2), have been synthesized by reactions of a single-armed salamo-based ligand, H3L, and two kinds of transition metal salts, (Zn(NO3)2·6H2O and Cd(OAc)2·2H2O), respectively. Complexes 1 and 2 have been characterized by elemental analyses, single crystal X-ray diffraction, IR spectra and UV-Vis spectra. Complex 1 is composed of a totally deprotonated ligand (L)3- moiety, two Zn(II) ions, one μ-PhCOO- counter-anion and one coordinated ethanol molecule. The (L)3- unit packages two Zn(II) ions, the μ-PhCOO- counter-anion bridges two adjacent Zn(II) ions and one ethanol molecule coordinates with the Zn2 ion, so that both Zn(II) ions are penta-coordinated with slightly distorted trigonal bipyramidal configurations, and the τ5 values of Zn1 and Zn2 are 0.86 and 0.65, respectively. Complex 2 consists of two discrete and similar electroneutral tetra-nuclear units, 2 A and 2B, and two crystallized dichloromethane molecules. Each unit has a symmetric structure that is made up of two completely deprotonated ligand (L)3- moieties, four Cd(II) ions, two η-OAc- counter-anions and two coordinated ethanol molecules. Fluorescence properties and Hirshfeld surfaces analyses have been studied as well. [ABSTRACT FROM AUTHOR]

The coordination behaviors of asymmetric quinoline-decorated half-salamo-type ligand HL1 with Cu(NO3)2·3H2O and Cu(OAc)2·H2O were studied. Two Cu(II) complexes, [Cu(L1)(NO3)]·CH3CH2OH (1) and [Cu2(L2)2] (2), were isolated and characterized by X-ray crystallography, FTIR, UV–vis, and fluorescence spectroscopies. Structural analyses showed that 1 is a mononuclear species, whereas 2 is a binuclear entity. Spontaneous cleavage along the oxime N-O bond close to quinoline ring of the ligand HL1 occurred upon reaction with Cu(OAc)2·H2O, yielding an unexpected complex 2. Moreover, DFT theoretical calculations and Hirshfeld surfaces analyses of the ligand HL1 and its corresponding Cu(II) complexes were investigated in detail. [ABSTRACT FROM AUTHOR]

d-Block transition metal(II)-lanthanide(III) (3d-4f) hetero‐trinuclear [Cu(II)2Ln(III)] (Ln = La and Ce) complexes [Cu2La(L)(ƞ2-NO3)3(CH3OH)2]·2CH3OH (1) and [Cu2Ce(L)(ƞ2-NO3)3(CH3OH)2]·2CH3OH (2) are described, both of which are formed by a flexible symmetrical bis(salamo)-type ligand H4L. The two 3d-4f complexes have been synthesized and characterized by elemental analyses, IR spectra and UV–Vis spectroscopy. The crystal structures of 1 and 2 were determined by single-crystal X-ray diffraction analyses. In 1 and 2, each Cu(II) ion (Cu1 or Cu2) is located in the N2O2 cavity of an (L)4− unit, while the apex is occupied by one oxygen atom of the coordinated methanol molecule, forming a penta-coordinated square pyramidal geometry. The lanthanide(III) (La or Ce) ion is located in the O6-donor coordination sphere of the completely deprotonated (L)4− unit and coordinated with the other six oxygen atoms of the three nitrate ligands to form a twelve-coordinated icosahedron. At the same time, the supramolecular structures are formed by intermolecular hydrogen bonding interactions and quantitatively determined by Hirshfeld surfaces analyses. Fluorescence properties and DFT calculations of 1 and 2 were also studied. [ABSTRACT FROM AUTHOR]

Two new tri-nuclear Co(II) and Ni(II) complexes, [{Co(L)(μ-OAc)(EtOH)}2Co]·2EtOH·2CH2Cl2 (1) and [{Ni(L)(μ-PhCOO)(MeOH)}2Ni]·2CH3OH·4H2O (2), were synthesized by complexing H2L (4-methylcoumarin-2,2′-[(propane-1,3-diyldioxy)bis(nitrilomethylidyne)]diphenol) with Co(OAc)2⋅4H2O and Ni(NO3)2·6H2O, respectively, and characterized by chemical-physical characterization. For 1, the crystallographic analysis revealed there are three Co(II) ions, two completely deprotonated ligands (L2–), two coordinated ethanol molecules and two bidentate bridging acetate groups (μ-OAc-). Complex 2 is composed of three Ni(II) ions, two completely deprotonated L2– ligands, two coordinated methanol molecules and two bidentate bridging benzoate groups (μ-PhCOO–). The fluorescence properties of 1 and 2 were studied. The supramolecular structures of 1 and 2 are formed by intermolecular hydrogen bonds or π-related interactions. The important intermolecular interactions of H2L and 1 and 2 were quantitatively determined by Hirshfeld surfaces analyses. In order to determine the kinetic stabilities of H2L, 1 and 2, DFT calculations were performed at B3LYP/SDD level of theory. [ABSTRACT FROM AUTHOR]

Four 3d–4f heteronuclear complexes, [(ZnL)2La(OAc)2]·ClO4·2CHCl3(1), [(ZnL)2La(OAc)2]·CF3SO3·H2O (2), [ZnNd(L)(Py)(NO3)3] (3), and [ZnGd(L)(OAc)(NO3)2] (4) (Py = pyridine; H2L = 6,6′-dimethoxy-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol), have been prepared by one-pot reaction of H2L with zinc(II) acetate, lanthanide(III) ions and Py. Although the heterobinuclear complexes1–4are prepared in the same reaction condition, the Py does not coordinate to Zn(II) of1,2,and4. Instead, the bridgingμ-acetato ligand is present. The coordination of the Py in3leads to smaller distortion of square pyramidal coordination site of Zn(II), the higher coplanarity between the planes of ZnO(phenoxo)2and LnO(phenoxo)2, and the longer Zn⋯Ln distance compared with4. The luminescence properties of1–4have been discussed. The ligand (L2−) can sensitize NIR luminescence of Nd(III) ions. [ABSTRACT FROM AUTHOR]