Dimeric copper(II) 3,3‐dimethyl­butyrate adducts with ethanol, 2‐methylpyridine, 3‐methylpyridine, 4‐methylpyridine and 3,3‐dimethylbutyric acid

In the crystals of the five title compounds, tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(ethanol‐O)dicopper(II)–ethanol (1/2), [Cu₂(C₆H₁₁O₂)₄(C₂H₆O)₂]·2C₂H₆O, (I), tetrakis(μ‐3,3‐dimethylbutyrato‐O:O′)bis(2‐methylpyridine‐N)di­copper(II), [Cu₂(C₆H₁₁O₂)₄(C₆H₇N)₂], (II), tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(3‐methylpyridine‐N)di‐copper(II), [Cu₂(C₆H₁₁O₂)₄(C₆H₇N)₂], (III), tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(4‐methylpyridine‐N)di‐copper(II), [Cu₂(C₆H₁₁O₂)₄(C₆H₇N)₂], (IV), and tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(3,3‐dimethylbutyric acid‐O)dicopper(II), [Cu₂(C₆H₁₁O₂)₄(C₆H₁₂O₂)₂], (V), the di­nuclear Cu^II complexes all have centrosymmetric cage structures and (IV) has two independent molecules. The Cu?Cu separations are: (I) 2.602 (3) Å, (II) 2.666 (3) Å, (III) 2.640 (2) Å, (IV) 2.638 (4) Å and (V) 2.599 (1) Å.     

(4‐Bromo‐2‐formyl­phenolato)­perchlorato­(1,10‐phenanthroline)­copper(II)

In the title copper(II) compound, [Cu(C₇H₄BrO₂)(ClO₄)(C₁₂H₈N₂)], the Cu atom is five‐coordinated in a distorted square‐pyramidal geometry by the N‐ and O‐donors of 4‐bromo‐2‐formyl­phenolate, 1,10‐phenanthroline and perchlorate. Pairs of complexes are linked together by Cu⋯O(phenolate) and π–π stacking inter­actions between 4‐bromo‐2‐formyl­phenolate and 1,10‐phenanthroline. Along the crystallographic a axis, the dimers are linked by hydrogen bonds between a perchlorate O atom and a 4‐bromo‐2‐formyl­phenolate H atom, and by further π–π stacking inter­actions. Hydrogen bonding between the Br atom and a 1,10‐phenanthroline H atom takes place between the stacks of dimers.     

Aqua­bis­(crotonato)­bis­(pyridine)­copper(II)

The title compound, [Cu(O₂CCH=CHCH₃)₂(C₅H₅N)₂(H₂O)], crystallizes as a monomer, with the copper ion in a pentacoordinated square‐pyramidal environment, bisected by a twofold axis passing through the metal atom and the apex. The mol­ecules organise in chains connected by hydrogen bonds running along the unique b axis.     

Bis(acesulfamato‐κ2O4,N)bis­(3‐methyl­pyridine)copper(II)

In the crystal structure of the title compound {systematic name: bis­[6‐methyl‐1,2,3‐oxa­thia­zin‐4(3H)‐one 2,2‐dioxide(1−)‐κ²N³,O⁴]bis­(3‐meth­yl­pyridine)copper(II)}, [Cu(C₄H₄NO₄S)₂(C₆H₇N)₂], the Cu^II centre resides on a centre of symmetry and has an octa­hedral geometry that is distorted both by the presence of four‐membered chelate rings and because of the Jahn–Teller effect. The equatorial plane is formed by the N atoms of two methyl­pyridine ligands and by the more basic O atoms of the acesulfamate ligands, while the weakly basic N atoms of these ligands are in elongated axial positions with a misdirected valence. The crystal is stabilized by two inter­molecular C—H⋯O inter­actions involving the methyl and CH groups, and the sulfonyl O atoms of the acesulfamate group.     

Bis­[2‐(pyrazol‐3‐yl)­phenolato‐κ2N2,O]copper(II) dimethanol solvate

The title compound, [Cu(C₉H₇N₂O)₂]·2CH₃OH, contains a crystallographically centrosymmetric near‐regular square planar Cu^II centre with trans‐disposed chelating ligands. The complex mol­ecules associate into a one‐dimensional polymeric chain via hydrogen bonding to the solvent mol­ecules.     

(Azido‐κN)bis­(di‐2‐pyridylamine)­copper(II) hexa­fluoro­phosphate and (azido‐κN)bis­(di‐2‐pyridylamine)­copper(II) chloride tetra­hydrate

The two new title complexes, [Cu(N₃)(dpyam)₂]PF₆ (dpyam is di‐2‐pyridylamine, C₁₀H₁₁N₃), (I), and [Cu(N₃)(dpyam)₂]Cl·4H₂O, (II), respectively, have been characterized by single‐crystal X‐ray diffraction. Both complexes display a distorted square‐pyramidal geometry. Each Cu atom is coordinated in the basal plane by three dpyam N atoms and one azide N atom in equatorial positions, and by another N atom from the dpyam group in the apical position. In complex (I), the one‐dimensional supra­molecular architecture is assembled via hydrogen‐bonding inter­actions between the amine N atom and terminal azide N atoms and the F atoms of the PF₆⁻ anion. For complex (II), hydrogen‐bonding inter­actions between the amine N atom, the Cl⁻ anion and water O atoms result in a two‐dimensional lattice.     

4‐[N,N‐Bis(2‐cyano­ethyl)­amino]­pyridine

The title compound, 3,3′‐(4‐pyridyl­imino)­di­propane­nitrile, C₁₁H₁₂N₄, has a twofold axis and consists of a pyridine ring head and two cyano­ethyl tails, the three groups being linked by an N atom. The planar geometry around the amino N atom suggests conjugation with the π‐system of the pyridine ring. The mol­ecules are stacked in a layer structure via relatively weak to very weak intermolecular C—H⃛π and C—H⃛N hydrogen‐bond interactions.     

Synthesis,characterization and in vitro biological assays of copper(II) and nickel(II) complexes with furan‐­2­‐carboxylic acid hydrazide

Two transition metal complexes, [Cu(FH)₃]⋅2Cl⋅2H₂O and [Ni(FH)₃]⋅2Cl⋅2H₂O, were synthesized from the reactions of furan‐2‐carboxylic acid hydrazide with CuCl₂⋅2H₂O and NiCl₂⋅6H₂O. The synthesized complexes were characterized using analytical and various spectral techniques. The structures of the complexes were determined using single‐crystal X‐ray diffraction. The interactions of the complexes with calf thymus DNA (CT‐DNA) were studied using absorption, fluorescence, cyclic voltammetric and viscosity measurements. The experimental results showed that the complexes could interact with CT‐DNA through intercalation. A gel electrophoresis assay demonstrated the ability of the complexes to cleave pBR322 DNA. The binding interaction of the complexes with bovine serum albumin was investigated using a fluorescence spectroscopic method. The radical scavenging ability, assessed using a series of antioxidant assays involving 2,2‐diphenyl‐2‐picrylhydrazyl radical, hydroxyl radical and nitric oxide radical, showed that the complexes possess significant radical scavenging properties. Further, the in vitro cytotoxic effect of the complexes examined on cancerous cell lines, such as human cervical cancer cells (HeLa) and human breast cancer cell line (MCF‐7), showed that the complexes exhibit significant anticancer activity.     

Bis(1‐ferrocenylbutane‐1,3‐dionato‐κ2O,O′)copper(II) and bis­(1,3‐diferrocenylpropane‐1,3‐dionato‐κ2O,O′)­copper(II)

The title compounds, [CuFe₂(C₅H₅)₂(C₉H₈O₂)₂], (I), and [CuFe₄(C₅H₅)₄(C₁₃H₉O₂)₂], (II), are four‐coordinate square‐planar copper(II) complexes with two bidentate 1‐ferrocenylbutane‐1,3‐dionate or 1,3‐diferrocenylpropane‐1,3‐dionate ligands, respectively. The copper ion in (I) lies on an inversion centre, with one‐half of the mol­ecule in the asymmetric unit, while in (II), there are two independent half mol­ecules in the asymmetric unit, with the copper ions also situated on inversion centres. The ferrocene substituents in (I) are in an anti arrangement. The mol­ecules assemble in the crystal structure in layers with ferrocene groups at the surface. The pairs of ferrocene substituents on each ligand in complex (II) are syn and these adopt an anti arrangement with respect to the pair on the other diketonate ligand. As found in (I), complexes assemble in a layered structure with ferrocene‐coated surfaces.     

(2‐Methyl­quinolin‐8‐olato)­iron(III) and ‐copper(II) complexes

The crystal structures of tris(2‐methyl­quinolin‐8‐olato‐N,O)­iron(III), [Fe­(C₁₀­H₈­NO)₃], (I), and aqua­bis(2‐methyl­quinolin‐8‐olato‐N,O)­copper(II), [Cu­(C₁₀­H₈NO)₂­(H₂O)], (II), have been determined. Compound (I) has a distorted octahedral configuration, in which the central Fe atom is coordinated by three N atoms and three O atoms from three 2‐methylquinolin‐8‐olate ligands. The three Fe—O bond distances are in the range 1.934 (2)–1.947 (2) Å, while the three Fe—N bond distances range from 2.204 (2) to 2.405 (2) Å. In compound (II), the central Cu^II atom and H₂O group lie on the crystallographic twofold axis and the coordination geometry of the Cu^II atom is close to trigonal bipyramidal, with the three O atoms in the basal plane and the two N atoms in apical positions. The Cu—N bond length is 2.018 (5) Å. The Cu—O bond length in the basal positions is 1.991 (4) Å, while the Cu—O bond length in the apical position is 2.273 (6) Å. There is an intermolecular OW—H?O hydrogen bond which links the mol­ecules into a linear chain along the b axis.     

Bis­[μ‐3{5}‐(2‐pyridyl)­pyrazolido]­bis­[(aceto­nitrile)copper(II)] diperchlorate

The title compound, [Cu₂(C₈H₆N₃)₂(C₂H₃N)₂](ClO₄)₂, con­tains a centrosymmetric dinuclear dication, with square‐pyrami­dal Cu^II centres linked by two 1,2‐pyrazolide bridging groups. There is a weak apical interaction between each Cu ion and a perchlorate O atom.     

Bis­[(R)‐3,5‐di­chloro‐N‐(1‐phenyl­ethyl)­salicyl­idene­aminato‐κ2N,O]­copper(II) and bis­[(R)‐3‐ethoxy‐N‐(1‐phenyl­ethyl)­salicyl­idene­aminato‐κ2N,O]copper(II)

The title compounds, [Cu(C₁₅H₁₂Cl₂NO)₂], (I), and [Cu(C₁₇­H₁₈NO₂)₂], (II), both adopt a compressed tetrahedral trans‐[CuN₂O₂] coordination geometry, the mol­ecules having an umbrella conformation overall. These complexes differ from one another with respect to the 1‐phenyl­ethyl­amine moieties, the direction of the benzene rings being either inside [in (I)] or inside and outside [in (II)] of the mol­ecules. The crystals of (I) and (II) have Δ(R,R) and Λ(R,R) absolute configurations, respectively.     

Tetra­aqua(2,2′‐bi­pyridine)­nickel(II) terephthalate

The reaction of nickel(II) nitrate with terephthalic acid and 2,2′‐bi­pyridine in di­methyl­form­amide solution gives the title complex, [Ni(C₁₀H₈N₂)(H₂O)₄](C₈H₄O₄). The Ni^II ion is octahedrally coordinated to one 2,2′‐bi­pyridine and four water mol­ecules and does not coordinate to the terephthalate anion. Hydro­gen bonds between the terephthalate anions and the [Ni(2,2′‐bipy)(H₂O)₄]²⁺ cations produce a two‐dimensional hydrogen‐bonding architecture with double sheets.     

3‐(4‐Cyano­phenyl)­pentane‐2,4‐dione and its copper(II) complex

The β‐diketone 3‐(4‐cyano­phenyl)­pentane‐2,4‐dione crystallizes as the enol tautomer 4‐(2‐hydroxy‐4‐oxopent‐2‐en‐3‐yl)­benzo­nitrile, C₁₂H₁₁NO₂, (I), with an intramolecular O—H⋯O hydrogen bond [O⋯O = 2.456 (2) Å]. Reaction of (I) with copper acetate monohydrate in the presence of triethyl­amine leads to the formation of the copper(II) complexbis­[3‐(4‐cyano­phenyl)­pentane‐2,4‐dionato‐κ²O,O]copper(II), [Cu(C₁₂H₁₀NO₂)₂], (II). In the structure of (II), the Cu atom is coordinated by four β‐diketonate O atoms in a slightly distorted square‐planar geometry, with Cu—O distances in the range 1.8946 (11)–1.9092 (11) Å. The nitrile moieties in (II) make it a candidate for reaction with other metal ions to produce supramolecular structures.     

μ‐Chloro‐bis{[benzylbis(2‐pyridyl­methyl)­amine‐κ3N]­chloro­copper(II)} perchlorate hemi­hydrate

In the title dinuclear Cu^II compound, [Cu₂Cl₃(C₁₉H₁₉N₃)₃]ClO₄·0.5H₂O, the coordination geometry around the Cu atoms is square pyramidal, with the bridging Cl atom at the apical positions. The Cu—Cl—Cu angle is 136.9 (1)° and the Cu?Cu distance is 4.961 (1) Å.