A newly synthesized visual bis(salamo)-based fluorescent chemosensor for exogenous detection of B4O72- in living cells and zebrafish.

A newly synthesized fluorescent chemosensor H6L was explored for detecting B4O72-, characterized by 1H NMR spectrum, mass spectrum and fluorescence spectra. During the detection process of B4O72-, the fluorescence is significantly enhanced and naked eye recognition can be performed under 365 nm UV light without any interference by other typical anions. The limit of detection is as low as 6.97 × 10-10 M. In addition, in order to broaden the application of salamo-based fluorescence sensors in the field of biology, except for the fluorescence imaging of HeLa cells, the first attempt of exogenous detection in zebrafish was conducted successfully.

Synthesis and Fluorescence Properties of Structurally Characterized Heterobimetalic Cu(II)⁻Na(I) Bis(salamo)-Based Complex Bearing Square Planar, Square Pyramid and Triangular Prism Geometries of Metal Centers.

A novel heterotrinuclear complex [Cu2(L)Na(µ-NO3)]∙CH3OH∙CHCl3 derived from a symmetric bis(salamo)-type tetraoxime H4L having a naphthalenediol unit, was prepared and structurally characterized via means of elemental analyses, UV-Vis, FT-IR, fluorescent spectra and single-crystal X-ray diffraction. The heterobimetallic Cu(II)⁻Na(I) complex was acquired via the reaction of H4L with 2 equivalents of Cu(NO3)2·2H2O and 1 equivalent of NaOAc. Clearly, the heterotrinuclear Cu(II)⁻Na(I) complex has a 1:2:1 ligand-to-metal (Cu(II) and Na(I)) ratio. X-ray diffraction results exhibited the different geometric behaviors of the Na(I) and Cu(II) atoms in the heterotrinuclear complex; the both Cu(II) atoms are sited in the N2O2 coordination environments of fully deprotonated (L)4− unit. One Cu(II) atom (Cu1) is five-coordinated and possesses a geometry of slightly distorted square pyramid, while another Cu(II) atom (Cu2) is four-coordination possessing a square planar coordination geometry. Moreover, the Na(I) atom is in the O6 cavity and adopts seven-coordination with a geometry of slightly distorted single triangular prism. In addition, there are abundant supramolecular interactions in the Cu(II)⁻Na(I) complex. The fluorescence spectra showed the Cu(II)⁻Na(I) complex possesses a significant fluorescent quenching and exhibited a hypsochromic-shift compared with the ligand H4L.

Synthesis, crystal structure and spectral properties of a supramolecular trinuclear nickel(II) complex with 5-methoxy-4'-bromo-2,2'-[ethylenedioxybis(nitrilomethylidyne)]diphenol.

A novel trinuclear Ni(II) complex [{NiL(n-PrOH)(µ-OAc)}2Ni]·n-PrOH·H2O with an asymmetric Salamo-type ligand, 5-methoxy-4'-bromo-2,2'-[ethylenedioxybis(nitrilomethylidyne)]diphenol (H2L), has been synthesized and characterized by elemental analyses, IR, UV/Vis and fluorescence spectra and molar conductance measurement. The crystal structure of the Ni(II) complex has been determined by single-crystal X-ray diffraction. Two acetate groups coordinating to three Ni(II) ions through NiOCONi bridges and four µ-phenoxo oxygen atoms from two [NiL(n-PrOH)] units also coordinating to Ni(II) ions. In the Ni(II) complex, two n-propanol molecules are coordinated to the two terminal Ni(II) ions having slightly distorted octahedral coordination geometries and form a trinuclear structure, There are also one non-coordinated n-propanol and one non-coordinated water molecule. In the crystal structure, the Ni(II) complex is linked by intermolecular hydrogen bonds into an infinite 1D supramolecular chain-like structure.

A novel trinuclear cobalt(II) complex derived from an asymmetric Salamo-type N2O3 bisoxime chelate ligand: synthesis, structure and optical properties.

A novel trinuclear Co(II) complex, {[CoL(PrOH)]2Co(H2O)}·PrOH, has been synthesized with 6-ethoxy-6'-hydroxy-2,2'-[ethylenedioxybis(nitrilomethylidyne)]diphenol (H3L), and characterized by elemental analyses, FT-IR, UV-Vis, molar conductance and X-ray crystallographic analysis. Two n-propanol molecules and one water molecule coordinate to three Co(II) ions and four µ-phenoxo oxygen atoms from two [CoL(CH3CH2CH2OH)] units also coordinating to Co(II) ion. All the penta-coordinated Co(II) ions of the Co(II) complex have a slightly distorted trigonal bipyramidal coordinated polyhedron. Meanwhile, the µ-phenoxo bridges play important roles in assembling Co(II) ions and L(3-) units, which is different from the normal trinuclear Co(II) complexes with the Salamo-type ligands reported early.

Synthesis, crystal structure and spectroscopic properties of a supramolecular zinc(II) complex with N2O2 coordination sphere.

A new hexa-coordinated zinc(II) complex, namely [ZnL(H2O)2]n, with N2O2 coordination sphere (H2L=4,4'-dibromo-6,6'-dichloro-2,2'-[ethylenedioxybis(nitrilomethylidyne)]diphenol) has been synthesized and structurally characterized by elemental analyses, IR, UV-vis spectra and TG-DTA analyses, etc. Crystallographic data are monoclinic, space group P2(1)/c, a=24.634(2)Å, b=10.144(1)Å, c=7.9351(6)Å, ß=91.371(2)°, V=1982.4(3)Å(3), Dc=2.099 g/cm(3), Z=4. The zinc(II) complex exhibits a slightly distorted octahedral geometry with halogen-substituted Salen-type bisoxime forming the basal N2O2 coordination sphere and two oxygen atoms from two coordinated water molecules in the axial position. The hydrogen-bonding and π-π stacking interactions have stabilized the zinc(II) complex molecules to form a self-assembling infinite dual metal-water chain-like structure with the nearest Zn⋯Zn distance of 4.954(4)Å.

4,4'-Dimeth-oxy-2,2'-[(butane-1,4-diyldi-oxy)bis-(nitrilo-methyl-idyne)]diphenol.

The title Schiff base bis-oxime compound, C(20)H(24)N(2)O(6), lies across an inversion centre and adopts an E configuration with respect to the C=N bond. In the mol-ecule, the oxime group is roughly coplanar with the benzene ring, forming a dihedral angle of 1.77 (2)°. An intra-molecular O-H⋯N hydrogen bond forms a six-membered ring with an S(6) motif. Weak inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure.

Bis{(E)-2-[1-(eth-oxy-imino)-eth-yl]-1-naphtho-lato-κN,O}copper(II).

In the title complex, [Cu(C(14)H(14)NO(2))(2)], the discrete complex mol-ecules have crystallographic inversion symmetry. The slightly distorted square-planar coordination sphere of the Cu(II) atom comprises two phenolate O atoms and two oxime N atoms from two bidentate-chelate 2-[1-(eth-oxy-imino)-eth-yl]-1-naphtho-late O-ethyl oxime (L(-)) ligands [Cu-O = 1.8919 (17) Šand Cu-N = 1.988 (2) Å]. The two naphthalene ring systems in the mol-ecule are parallel, with a perpendicular inter-planar spacing of 1.473 (2) Å, while each complex unit forms links to four other mol-ecules via inter-molecular methyl C-H⋯π inter-actions, giving an infinite cross-linked layered supra-molecular structure.