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An asymmetric salamo‐based probe molecule (H2L) was synthesized and characterized structurally. When DMF/H2O (9:1) was used as the solvent, it was shown probe H2L has high sensitivity to Cu2+. Using high‐resolution mass spectrometry and theoretical calculation, it was found that probe H2L could form a more stable complex (1:1) with Cu2+, the minimum limit of detection (LOD) of H2L for Cu2+ was calculated as 9.95 × 10−8 M. In addition, probe H2L could also be used to identify B4O72− under the same detection conditions and the minimum LOD of H2L for B4O72− was calculated as 4.98 × 10−7 M. At the same time, density functional theory theoretical calculation further proved the flexibility of probe H2L. Through the action of EDTA, probe H2L had a cyclic ability to recognize Cu2+, and showed a better response in the physiological pH range; probe H2L had the characteristics of fast recognition speed and high efficiency. In addition, with probe H2L test paper for Cu2+ and B4O72−, the effect was more obvious. Meanwhile, probe H2L can be used to quantitatively detect Cu2+ in water samples. [ABSTRACT FROM AUTHOR]

Four new solvent‐induced Ni(II) complexes with chemical formulae [{NiL(μ2‐OAc)(MeOH)}2Ni]·2MeOH (1), [{NiL(μ2‐OAc)}2(n‐PrOH)(H2O)Ni]·n‐PrOH (2), [{NiL(μ2‐OAc)(DMF)}2Ni] (3) and [{NiL(μ2‐OAc)(DMSO)}2Ni]·2DMSO (4), (H2L = 4‐Nitro‐4′‐chloro‐2,2′‐[(1,3‐propylene)dioxybis(nitrilomethylidyne)]diphenol) have been synthesized and characterized by elemental analyses, FT‐IR, UV–Vis spectra and X‐ray crystallography. X‐ray crystal structure determinations revealed that each of the Ni(II) complexes 1–4 consists of three Ni(II) atoms, two completely deprotonated (L)2− units, two μ2‐acetate ions and two coordinated solvent molecules (solvents are methanol, n‐propanol, water, N,N‐dimethylformamide and dimethyl sulphoxide, respectively). Although the four complexes 1–4 were synthesized in different solvents, it is worthwhile that the Ni(II) atoms in the four complexes 1–4 adopt hexa–coordinated with slightly distorted octahedral coordination geometries, and the ratios of the ligand H2L to Ni(II) atoms are all 2: 3. The complexes 1–4 possess self‐assembled infinite 1D, 3D, 1D and 2D supramolecular structures via the intermolecular hydrogen bonds, respectively. In addition, fluorescence behaviors were investigated in the complexes 1–4. [ABSTRACT FROM AUTHOR]

A novel naphthalenediol‐based bis(salamo)‐type tetraoxime compound (H4L) was designed and synthesized. Two new supramolecular complexes, [Cu3(L)(μ‐OAc)2] and [Co3(L)(μ‐OAc)2(MeOH)2]·4CHCl3 were synthesized by the reaction of H4L with Cu(II) acetate dihydrate and Co(II) acetate dihydrate, respectively, and were characterized by elemental analyses and X‐ray crystallography. In the Cu(II) complex, Cu1 and Cu2 atoms located in the N2O2 sites, and are both penta‐coordinated, and Cu3 atom is also penta‐coordinated by five oxygen atoms. All the three Cu(II) atoms have geometries of slightly distorted tetragonal pyramid. In the Co(II) complex, Co1 and Co3 atoms located in the N2O2 sites, and are both penta‐coordinated with geometries of slightly distorted triangular bipyramid and distorted tetragonal pyramid, respectively, while Co2 atom is hexa‐coordinated by six oxygen atoms with a geometry of slightly distorted octahedron. These self‐assembling complexes form different dimensional supramolecular structures through inter‐ and intra‐molecular hydrogen bonds. The coordination bond cleavages of the two complexes have occurred upon the addition of the H+, and have reformed again via the neutralization effect of the OH−. The changes of the two complexes response to the H+/OH− have observed in the UV–Vis and 1H NMR spectra. [ABSTRACT FROM AUTHOR]

A new tetranuclear Zn( II) complex, [{Zn(L)(μ- OAc)Zn( H2O)}2], based on an asymmetrical salamo-type bisoxime chelating ligand H3L (6-hydroxy-4′-chloro-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol) was synthesized and characterized by elemental analyses, differential thermal methods, single-crystal X-ray crystallography, and IR, UV-vis, and fluorescence spectra. The Zn( II) complex crystallizes in the triclinic system, space group P-1 with cell parameters a = 9.0742(6) Å, b = 11.8225(5) Å, c = 12.4182(8) Å, Z = 2, V = 1212.56(12) Å3, R1 = 0.0572, and wR2 = 0.1734. The environment of the tetranuclear Zn(II) complex is penta-coordinated having a slightly distorted trigonal bipyramidal geometry. Moreover, a 1D chain supramolecular structure is formed along the c-axis by the intermolecular C1-H1B⋯O14 hydrogen bonds; in the same manner, C2-H2C⋯Cg2 functions in the formation of supramolecular structures along the a-axis of the 1D chain. A 2D supramolecular structure along the ac plane extends infinitely under the force of intermolecular hydrogen bonds. Differential scanning calorimetry-thermogravimetry thermal analysis provides evidence of the coordination of Zn(II) atoms to the ligand H3L. The Zn(II) complex shows intense photoluminescence with a maximum emission at ~453 nm upon excitation at 360 nm. [ABSTRACT FROM AUTHOR]

Mononuclear copper(II) and trinuclear cobalt(II) complexes, namely [Cu(L1)]2 ·CH2Cl2 and [{Co(L2)(EtOH)}2Co(H2O)] ·EtOH {H2L1 = 4,6-dichloro-6′-methyoxy-2,2′-[1,1′-(ethylenedioxydinitrilo)dimethylidyne]diphenol and H3L2 = 6-ethyoxy-6′-hydroxy-2,2′-[1,1′-(ethylenedioxydinitrilo)dimethylidyne]diphenol}, were synthesized and characterized by elemental analyses, IR and UV/Vis spectroscopy, and single-crystal X-ray diffraction. In the CuII complex, the CuII atom is four-coordinate, with a N2O2 coordination sphere, and has a slightly distorted square-planar arrangement. Interestingly, the obtained trinuclear CoII complex is different from the common reported 2:3 (L:CoII) salamo-type CoII complexes. Infinite 2D layer supramolecular structures are formed via abundant intermolecular hydrogen bonding and π ···π stacking interactions in the CuII and CoII complexes. [ABSTRACT FROM AUTHOR]

A Salamo-type ligand 6,6′-diethoxy-2,2′-[1,1′-(ethylenedioxydinitrilo)dimethylidyne]diphenol (H2L) and its pentacoordinate copper(II) complex [CuL(H2O)] were synthesized and structurally characterized. The molecule of H2L is located in a crystallographic inversion center and adopts E configuration with respect to the C=N bond. In the complex [CuL(H2O)], the CuII atom has a tetragonally elongated square-pyramidal configuration with donor atoms N2O2 forming a perfect basal plane. And an infinite 2D layer supramolecular structure is formed through intermolecular C1-H1A ···O5 and C2-H2A ···O3 hydrogen bonding interactions. [ABSTRACT FROM AUTHOR]

Two nickel(II) complexes, namely {[NiL(MeOH)(μ-OAc)]2Ni} ·2CH2Cl2 ·2MeOH ( 1) and {[NiL(EtOH)(μ-OAc)]2Ni} ·2EtOH ( 2) {H2L = 5, 5′-dimethoxy-2, 2′-[(ethylene)dioxybis(nitrilomethylidyne)]diphenol}, were synthesized and structurally characterized. Two trinuclear NiII complexes are both hexacoordinate around the central NiII atoms, showing octahedral coordination arrangements, and each complex comprises three divalent NiII atoms, two deprotonated L2- ligands, in which four μ-phenoxo oxygen atoms forming two [NiL( X)] ( X = MeOH or EtOH) units, and coordinated and non-coordinated solvent molecules. Complex 1 exhibits a 2D supramolecular network through intermolecular O-H ···O, C-H ···O and C-H ···π interactions, whereas complex 2 forms an infinite 1D chain by intermolecular C-H ···O hydrogen bonding interactions. [ABSTRACT FROM AUTHOR]

Three multinuclear Cu (II), Zn (II) and Cd (II) complexes, [Cu2(L)(μ‐OAc)]·CHCl2 (1), [Zn2(L)(μ‐OAc)(H2O)]·3CHCl3 (2) and [{Cd2(L)(OAc)(CH3CH2OH)}2]·2CH3CH2OH (3) with a single‐armed salamo‐like dioxime ligand H3L have been synthesized, and characterized by FT‐IR, UV–vis, X‐ray crystallography and Hirshfeld surfaces analyses. The ligand H3L has a linear structure and C‐H···π interactions between the two molecules. The complex 1 is a dinuclear Cu (II) complex, Cu1 and Cu2 are all five‐coordinate possessing distorted square pyramidal geometries. The complex 2 also forms a dinuclear Zn (II) structure, and Zn1 and Zn2 are all five‐coordinate bearing distorted trigonal bipyramidal geometries. The complex 3 is a symmetrical tetranuclear Cd (II) complex, and Cd1 is a hexa‐coordinate having octahedral configuration and Cd2 is hepta‐coordinate with a pentagonal bipyramidal geometry, and it has π···π interactions inside the molecule. In addition, fluorescence properties of the ligand and its complexes 1–3 have also been discussed. [ABSTRACT FROM AUTHOR]

Three newly designed containing‐PMBP N2O2‐donors complexes, [Co(L1)(CH3OH)2] (1), [{Zn(L2)(CH3OH)(H2O)}3] (2) and [Cu4(L2)4]⋅2CHCl3 (3), have been synthesized and structurally characterized using elemental analyses, infrared and UV–visible spectroscopies and single‐crystal X‐ray diffraction. X‐ray crystal structure determinations revealed that 1 consists of one Co(II) atom, one completely deprotonated (L1)2− unit and two coordinated methanol molecules. Complex 2 consists of three Zn(II) atoms, three completely deprotonated (L2)2− units, three coordinated methanol molecules and three coordinated water molecules. However, 3 includes four Cu(II) atoms, four completely deprotonated (L2)2− units and two crystallization chloroform molecules. The Co(II) and Zn(II) atoms in the structures of 1 and 2 adopt slightly distorted octahedral geometries. While, Cu(II) atoms in 3 can be best described as adopting slightly distorted square planar geometries. Complex 2 is a novel structure, and the ratio of H2L2 to Zn(II) atom is 3:3. In addition, two‐, three‐ and three‐dimensional supramolecular structures were constructed for 1, 2 and 3. Most importantly, Hirshfeld surface analysis of 1, 2 and 3 was conducted and fluorescence properties were investigated. [ABSTRACT FROM AUTHOR]

Rare homo‐ and hetero‐polynuclear transition metal(II) complexes, [{Cu(L1)}2] (1) and [Cu(L2)Ni2(CH3OH)2] (2), were prepared and structurally characterized. Complex 1 possesses an uncommon dinuclear structure bonded by two alkoxy bridges, and all the Cu(II) atoms are tetra‐coordinated with slightly distorted square planar geometries. The Cu1─Cu2 bond distance is 2.994(3) Å. Complex 2 exhibits an unexpected trinuclear heterobimetallic structure from two chelating (L2)3− units in crossover mode, which is the first heterobimetallic 3d–3d salamo‐type transition metal complex. The two Ni(II) atoms are penta‐coordinated with slightly distorted square pyramidal geometries (τ = 0.269 (Ni1) and 0.498 (Ni2)), and the Cu(II) atom is tetra‐coordinated with a slightly distorted square planar geometry. Moreover, fluorescence behaviors of 1 and 2 were investigated, and electrochemical study reveals that the electrolytic redox reactions of 1 are irreversible processes. Rare homo‐ and hetero‐polynuclear transition metal(II) complexes, [{Cu(L1)}2] (1) and [Cu(L2)Ni2(CH3OH)2] (2), were prepared and characterized. Complex 1 possesses an uncommon dinuclear structure bonded by two alkoxy bridges. Complex 2 exhibits an unexpected trinuclear heterobimetallic structure from two chelating (L2)3− units in crossover mode. Fluorescence behaviors of 1 and 2 were investigated, and electrochemical experiments revealed that electrolytic redox reactions of 1 are irreversible processes. [ABSTRACT FROM AUTHOR]