Synthesis and characterization of macrocyclic and polymeric Schiff base complexes derived from related macrocyclic ligands in the presence of Ni(II) and Cu(II)

Crystal structure and photoluminescence properties of a new monomeric copper(II) complex: bis(3-{[(3-hydroxypropyl)imino]methyl}-4-nitrophenolato-κ3O,N,O')copper(II)

Copper(II)-Schiff base complexes have attracted extensive interest due to their structural, electronic, magnetic and luminescence properties. The title novel monomeric Cu^II complex, [Cu(C₁₀H₁₁N₂O₄)₂], has been synthesized by the reaction of 3-{[(3-hydroxypropyl)imino]methyl}-4-nitrophenol (H₂L) and copper(II) acetate monohydrate in methanol, and was characterized by elemental analysis, UV and IR spectroscopies, single-crystal X-ray diffraction analysis and a photoluminescence study. The Cu^II atom is located on a centre of inversion and is coordinated by two imine N atoms, two phenoxy O atoms in a mutual trans disposition and two hydroxy O atoms in axial positions, forming an elongated octahedral geometry. In the crystal, intermolecular O-H...O hydrogen bonds link the molecules to form a one-dimensional chain structure and π-π contacts also connect the molecules to form a three-dimensional structure. The solid-state photoluminescence properties of the complex and free H₂L have been investigated at room temperature in the visible region. When the complex and H₂L are excited under UV light at 349 nm, the complex displays a strong green emission at 520 nm and H₂L displays a blue emission at 480 nm.

Crystal structure and photoluminescence properties of a new CdIIcoordination polymercatena-poly[bis[4-bromo-2-({[2-(pyrrolidin-1-yl)ethyl]imino}methyl)phenolato-κ3N,N′,O]di-μ3-chlorido-di-μ2-chlorido-bis(methanol-κO)tricadmium(II)]

Schiff base–metal complexes have been used widely as catalysts for many organic reactions, such as ring-opening polymerization and oxidation. In view of the importance of CdIIcoordination polymers and in an effort to enlarge the library of such complexes, the title novel polymeric CdIItridentate Schiff base complex, [Cd3(C13H16BrN2O)2Cl4(CH4O)2]n, has been synthesized and characterized by elemental analyses, UV and IR spectroscopies, and single-crystal X-ray diffraction. The complex crystallizes in the triclinicP\overline{1} space group with two symmetry-independent CdIIatoms, one of which lies on an inversion centre, and analysis of the crystal structure shows that both CdIIatoms are six-coordinated; the environment around one CdIIatom can be described as distorted octahedral, while that around the second CdIIatom is octahedral. The CdIIatoms are linked by chloride ligands to form a one-dimensional coordination polymer. The nonbonding intermolecular Cd...Cd distances are 3.7009 (4) and 4.3563 (5) Å. Furthermore, the photoluminescence properties of the complex have been investigated and it displays a strong red emission in the solid state at room temperature.