Construction of Two Discrete Molecular High-Nuclearity Copper(II) Complexes as Heterogeneous Catalysts for Oxidative Coupling Polymerisation of 2,6-Dimethylphenol

Synthesis, structures and photoluminescence properties of mixed ligand divalent metal–organic frameworks

Crystal engineering is an effective route for synthesis of mixed ligand metal–organic frameworks with attractive topologies and versatile potential applications.

Constructing novel Cd(ii) metal–organic frameworks based on different highly connected secondary building units via alteration of reaction conditions

Upon the reaction of Cd(ii) ions and 4-Ptz ligands under different conditions, three new Cd(ii) metal–organic frameworks were constructed based on different highly connected secondary building units.

Group Position-Dependent Structurally Diverse Coordination Compounds Based on Isomeric Ligands

Two isomeric ligands Htzpya and Hpytza (Htzpya = 3-(5-tetrazolyl)pyridine-1-acetic acid, Hpytza = 5-(3-pyridyl)tetrazole-2-acetic acid) have been selected to react with DyCl3·6H2O or PrCl3·6H2O under hydrothermal conditions, resulting in the formation of four new coordination compounds, mononuclear [Dy(tzpya)2(H2O)5]Cl·4H2O (1), dinuclear [Pr2(tzpya)2(H2O)12]Cl4·2H2O (2), and two one-dimensional polymers [Dy(pytza)2Cl(H2O)2]n (3) and [Pr(pytza)2Cl(H2O)2]n (4), whose structures are controlled by the different positions of the carboxylate group. These compounds were characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. Compounds 1–4 are self-assembled to form three-dimensional network structures by hydrogen bonding interactions. Furthermore, the luminescence properties were also investigated at room temperature in the solid state.

Efficient oxidative coupling of 2,6-disubstituted phenol catalyzed by a dicopper(II) complex

Complexation of a rigid multi-pyridine ligand bis(2-pyridyl)-1,8-naphthyridine (bpnp) with [Cu(2)(TFA)(4)] (TFA = trifluoroacetate) resulted in the formation of a dinuclear copper(II) complex, namely [Cu(2)(bpnp)(μ-OH)(TFA)(3)] (1). This complex has been characterized by X-ray crystallographic, spectroscopic and elemental analyses. Complex 1 is an efficient catalyst for the oxidative coupling of various 2,6-disubstituted phenols with molecular oxygen. Yields and selectivity depend on the reaction conditions employed, the best results being obtained in isopropanol or dioxane at 90 °C with yields of >99%. Mechanistic pathway of the catalysis is discussed.