Syntheses and crystal structures of two copper(II) complexes derived from 2-bromo-4-chloro-6-[(2-morpholin-4-ylethylimino)methyl]phenol

Two new copper(II) complexes, [CuL₂] (1) and [Cu₂L₂(NCS)₂] · 2CH₃CN (2) (HL = 2-bromo-4-chloro-6-[(2-morpholin-4-ylethylimino)methyl]phenol), have been synthesized and characterized by elemental analyses, infrared spectroscopy, and single-crystal X-ray diffraction. Complex 1 was synthesized by reaction of HL with copper(II) acetate in methanol, while 2 was synthesized by adding ammonium thiocyanate to a methanol/acetonitrile (V : V = 2 : 1) solution of 1. Complex 1 crystallizes in the P2₁/n space group, and the thiocyanato-bridged dinuclear copper(II) complex, 2, crystallizes in the Pbcn space group. The Cu in 1 is four-coordinate square-planar with two imine N and two phenolate O atoms from two Schiff-base ligands. The Cu in 2 is five-coordinate square-pyramidal with NNO donor atoms of one Schiff-base ligand and one N atom of a bridging thiocyanate ligand defining the basal plane, and with one S atom of another bridging thiocyanate ligand occupying the apical position.     

Synthesis,crystal structures,and antimicrobial activity of copper(II) and zinc(II) complexes derived from 2-bromo-4-chloro-6-[(2-morpholin-4-ylethylimino)methyl]phenol

An end-to-end azido-bridged dinuclear copper(II) complex [Cu₂L₂(μ_1,3-N₃)](NO₃) (I) and a mononuclear zinc(II) complex [ZnCl₂(HL)] ? CH₃OH (II), where L is 2-brom-4-chloro-6-[(2-morpholin- 4-ylethylimino)methyl]phenolate, have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination (CIF files CCDC nos. 1415217 (I), 1415218 for (II)). The crystal of I is monoclinic: space group C2/c, a = 28.684(2), b = 7.1787(5), c = 18.292(1) Å, β = 117.887(3)°, V = 3329.1(4) ų, Z = 4. The crystal of II is monoclinic: space group P2₁/c, a = 10.8207(9), b = 12.3398(7), c = 14.9477(7) Å, β = 93.473(3)°, V = 1992.2(2) ų, Z = 4. The Schiff base ligand in I coordinates to the Cu atom through the phenolate O, imine N, and morpholine N atoms, while the Schiff base ligand in II coordinates to the Zn atom through the phenolate O and imine N atoms, with the morpholine N atom protonated. The effect of these complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans was studied.     

Synthesis and crystal structures of cobalt(III) and zinc(II) complexes derived from 4-chloro-2-[(2-morpholin-4-ylethylimino)methyl]phenol with urease inhibitory activity

A new mononuclear cobalt(III) complex, [CoL₂(N₃)]₂ · CH₃OH (I), and a new mononuclear zinc(II) complex, [ZnLCl(CH₃OH)] (II) (HL = 4-chloro-2-[(2-morpholin-4-ylethylimino)methyl]phenol), were prepared and structurally characterized by elemental analyses, infrared spectroscopy, and single- crystal X-ray diffraction. The crystal of I is monoclinic: space group P2₁/c, a = 18.742(2) Å, b = 15.197(2) Å, c = 25.646(2) Å, β = 125.996(3)°, V = 5909.8(11) ų, Z = 4. The crystal of II is monoclinic: space group P2₁/c, a = 7.257(1) Å, b = 24.707(2) Å, c = 9.637(1) Å, β = 101.557(2)°, V = 1692.9(3) ų, Z = 4. The Co atom in I is in an octahedral coordination, and the Zn atom in II is in a trigonal-bipyramidal coordination. The urease inhibitory test shows that complex I has strong urease inhibitory activity, while complex II has no activity.     

Synthesis,crystal structures,and antibacterial activities of two copper(II) complexes derived from 1-[(2-morpholin-4-ylethylimino)methyl]-naphthalen-2-ol

A trinuclear complex, [Cu(Cu(μ-Br)₂L)₂], and a dinuclear complex, [Cu₂(μ-Cl)₂L₂], have been synthesized with the tridentate Schiff base 1-[(2-morpholin-4-ylethylimino)methyl]-naphthalen-2-ol (HL), derived from 2-hydroxy-1-naphthyaldehyde and 4-(2-aminoethyl)morpholine. Both complexes have been characterized by physicochemical and spectroscopic methods. [Cu(Cu(μ-Br)₂L)₂] is a centrosymmetric bromide and phenolate oxygen-bridged trinuclear compound, while complex [Cu₂(μ-Cl)₂L₂] is a centrosymmetric-chloride-bridged dinuclear compound. The central Cu(II) atom in [Cu(Cu(μ-Br)₂L)₂] is six-coordinated in an octahedral coordination, while other Cu(II) atoms in both complexes are five-coordinated in square-pyramidal coordinations. Both complexes and HL were tested in vitro for their antibacterial activities.     

Syntheses and crystal structures of copper(II) and nickel(II) complexes derived from 2-bromo-4-chloro-6-[(2-methylaminoethylimino)methyl]phenol

A new centrosymmetric mononuclear copper(II) complex [Cu(L)₂](ClO₄)₂ (I) and a new centrosymmetric mononuclear nickel(II) complex [Ni(L)₂(MeOH)₂](ClO₄)₂ (II), where L is the zwitterionic ligand 2-bromo-4-chloro-6-[(2-methylammonioethylimino)methyl]phenolate, have been prepared from the Schiff base 2-bromo-4-chloro-6-[(2-methylaminoethylimino)methyl]phenol with copper perchlorate and nickel perchlorate, respectively. The complexes were characterized by elemental analysis, infrared spectra, and single-cyrstal X-ray diffraction (CIF files CCDC nos. 1408054 (I) and 1407973 (II)). Complex I crystallizes in the monoclinic space group P2₁/c with unit cell dimensions a = 7.7736(4), b = 21.608(1), c = 8.5194(4) Å, β = 93.907(2)°, V = 1427.7(1) ų, Z = 2, R ₁ = 0.0546, and wR ₂ = 0.1531. Complex II crystallizes in the monoclinic space group P2₁/c with unit cell dimensions a = 21.324(3), b = 16.821(2), c = 9.425(1) Å, β = 90.114(2)°, V = 3380.5(7) ų, Z = 4, R ₁ = 0.0693, and wR ₂ = 0.1627. The Cu atom in I is in square planar coordination, and the Ni atom in II is in octahedral coordination.     

Synthesis,crystal structures,and antimicrobial activity of two thiocyanato-bridged dinuclear copper(II) complexes derived from 2,4-dibromo-6-[(2-diethylaminoethylimino)methyl]phenol and 4-nitro-2-[(2-ethylaminoethylimino)methyl]phenol

A pair of structurally similar thiocyanato-bridged dinuclear Cu(II) complexes derived from the Schiff bases 2,4-dibromo-6-[(2-diethylaminoethylimino)methyl]phenol and 4-nitro-2-[(2-ethylaminoethylimino)methyl]phenol has been prepared and characterized by physico-chemical and spectroscopic methods. Each Cu atom is five-coordinate in a square-pyramidal geometry, with one O and two N atoms of one Schiff base ligand and one N atom of a bridging thiocyanate ligand defining the basal plane, and with one terminal S atom of another bridging thiocyanate ligand occupying the apical position. Antimicrobial activities of the Schiff bases and the two complexes have been tested. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Crystal structures of bis(AZIDO)bis(2-morpholin-4-ylethylamino)copper(II) and bis{2,4-dibromo-6-[(2-morpholin-4-ylethylimino)methyl] phenolato}copper(II)

Two new copper(II) complexes [Cu(MEA)₂(N₃)₂] (1) and [Cu(BMP)₂] (2), where MEA and BMP are 2-morpholin-4-ylethylamine and 2,4-dibromo-6-[(2-morpholin-4-ylethylimino)methyl]phenolate respectively, are prepared and characterized using elemental analysis, FT-IR spectroscopy, and X-ray single crystal diffraction. The crystal of 1 belongs to the triclinic system, space group P-1, with a = 6.661(2) Å, b = 8.440(3) Å, c = 8.913(3) Å, α = 102.032(3)°, β = 107.899(2)°, γ = 98.242(3)°, V = 454.6(3) ų, Z = 1, D _c = 1.490 g/cm³, R ₁ = 0.0226, and wR ₂ = 0.0564. The crystal of 2 belongs to the monoclinic system, space group P2₁/c, with α = 7.0707(7) Å, b = 15.438(1) Å, c = 14.227(1) Å, β = 96.659(2)°, V = 1542.5(3) ų, Z = 2, D _c = 1.821 g/cm³, R ₁ = 0.0437, and wR ₂ = 0.1041. In each complex, the Cu atom is in a square planar coordination. The molecules of 1 are linked through intermolecular N-H...N and N-H...O hydrogen bonds to form layers parallel to the ab plane. The molecules of 2 are linked through intermolecular C-H...Br hydrogen bonds to form a 3D network.     

Synthesis, crystal structures, and biological activity of zinc(II) complexes derived from 4-bromo-2-[(3-diethylaminopropylimino)methyl]phenol

Two new Schiff base zinc(II) complexes, [ZnBr₂L] (I) and [ZnCl₂L] (II), where L is 4-bromo-2-[(3-diethylaminopropylimino)methyl]phenol, were synthesized and characterized by physico-chemical methods and single crystal X-ray diffraction. The crystal of I is monoclinic: space group P2₁/n a = 7.250 (2), b = 16.136 (3), c = 15.802 (3) Å, β = 90.027 (3)°, V = 1848.6 (7) ų, Z = 4. The crystal of II is monoclinic: space group P2₁/n, a = 7.177 (3), b = 15.970 (4), c = 15.689 (3), β = 91.674 (3)°, V = 1797.5 (9) ų, Z = 4. The Zn atom in each complex is four-coordinated by one phenolate O and one imine N atoms of the Schiff base ligand and two halide atoms, forming a tetrahedral coordination. The urease inhibitory activities of the complexes were evaluated.     

Synthesis,crystal structures,and antimicrobial activity of a pair of isostructural dinuclear copper(II) complexes derived from 4-nitro-2-[(2-diethylaminoethylimino)methyl]phenol

A pair of isostructural azido- or thiocyanato-bridged centrosymmetric dinuclear copper(II) complexes, [Cu₂L₂(μ_1,3-N₃)₂] (1) and [Cu₂L₂(μ_1,3-NCS)₂] (2), derived from the Schiff base ligand 4-nitro-2-[(2-diethylaminoethylimino)methyl]phenol (HL), have been synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. Each Cu atom in the complexes is five-coordinate in a square pyramidal geometry by one O and two N atoms of one Schiff base ligand, and by two terminal donor atoms from two bridging azide or thiocyanate ligands. Both the azide and thiocyanate ligands adopt end-to-end bridging mode in the complexes. The distance between the two copper atoms is 5.205(2) Å for (1) and 5.515(2) Å for (2). The antimicrobial activity of the complexes has been tested.     

Solvent-influenced syntheses and crystal structures of two azido-bridged polynuclear copper(II) complexes derived from 2-[(3-methylaminopropylimino)methyl]phenol with urease inhibitory activities

An end-on azido-bridged dinuclear Cu(II) complex, [Cu₂L₂(μ_1,1–N₃)₂]·CH₃OH, and an end-on azido-bridged polynuclear Cu(II) complex, [CuL(μ_1,1–N₃)]_n, derived from the Schiff base 2-[(3-methylaminopropylimino)methyl]phenol (HL), were synthesized and characterized by physico-chemical and spectroscopic methods. The two complexes were synthesized and crystallized with different solvents, methanol for [Cu₂L₂(μ_1,1–N₃)₂]·CH₃OH and ethanol for [CuL(μ_1,1–N₃)]_n. The Cu atom in each complex is five-coordinate in a square pyramidal geometry with one O and two N atoms of L, and one N atom of an azide ligand defining the basal plane, and with one N atom of another azide ligand occupying the apical position. The urease inhibitory activities of both complexes were evaluated.     

Synthesis,crystal structures,and antibacterial activity of copper(II) and cobalt(III) complexes derived from 2-[(2-dimethylaminoethylimino)methyl]-4-methylphenol

A new tetranuclear copper(II) complex (I) and a new mononuclear cobalt(III) complex (II) have been synthesized from the Schiff base compound 2-[(2-dimethylaminoethylimino)methyl]-4-methylphenol. The complexes have been characterized by physico-chemical and spectroscopic methods, as well as single crystal X-ray determination (CIF files CCDC nos. 1447778 (I) and 1447779 (II)). The Cu atoms in complex I are in square pyramidal coordination, and the Co atom in complex II is in octahedral coordination. Crystal structures of the complex are stabilized by hydrogen bonds and π···π interactions. The complexes and the Schiff base compound were assayed for antibacterial activities against three Gram-positive bacterial strains (B. subtilis, S. aureus, and St. faecalis) and three Gram-negative bacterial strains (E. coli, P. aeruginosa, and E. cloacae) by MTT method. As a result, the complexes showed effective antimicrobial activity against the microorganisms tested.     

Syntheses,crystal structures,and urease inhibitory properties of copper(II) and zinc(II) complexes with 2-bromo-4-chloro-6-[(2-dimethylaminoethylimino)methyl]phenol

A new copper(II) complex, [CuL(μ _1,1-N₃)] _n (1), and a new zinc(II) complex, [ZnL(μ ₂-acetato-O, O′)₂] _n (2) (HL = 2-bromo-4-chloro-6-[(2-dimethylaminoethylimino)methyl]phenol), were prepared and characterized by elemental analyses, infrared spectroscopy, and single-crystal X-ray diffraction. Complex 1 is an end-on azide-bridged polynuclear copper(II) complex and 2 is a syn–anti bidentate acetate-bridged polynuclear zinc(II) complex. Each metal in the complex is five-coordinate with square-pyramidal geometry. Complex 1 shows good urease inhibitory properties, while 2 does not.     

Synthesis and crystal structures of two zinc(II) complexes derived from 4-bromo-2-(cyclopentyliminomethyl)phenol with different solvents

Two new mononuclear zinc(II) complexes, [ZnL₂] (I) and [ZnL₂] · 2MeOH (II) (HL = 4-bromo-2-(cyclopentyliminomethyl)phenol), were synthesized by the reaction of the Schiff base HL with zinc acetate in ethanol and methanol solutions, respectively. Both complexes were characterized by elemental analyses and single-crystal X-ray diffraction. The crystal of I is orthorhombic: space group Pbca, a = 14.711(3), b = 13.223(3), c = 24.870(5) Å, V = 4837.8(18) ų, Z = 8. The crystal of II is monoclinic: space group C2/c, a = 20.581(5), b = 10.660(3), c = 15.428(4) Å, β = 119.919(3)°, V = 2933.7(13) ų, Z = 4. The Zn atom in each complex is four-coordinated by two imine N and two phenolic O atoms, forming a tetrahedral geometry. Complex II possesses crystallographic two-fold rotation axis symmetry.     

Zinc(II) and nickel(II) complexes derived from 2-bromo-6-[(2-Isopropylaminoethylimino)methyl]phenol: Synthesis,structures, and antimicrobial activity

The Schiff base 2-bromo-6-[(2-isopropylaminoethylimino)methyl]phenol (HL), derived from 3-bromosalicylaldehyde with N-isopropylethane-1,2-diamine, and its zinc(II) and nickel(II) complexes [Zn(HL)₂(NCS)₂] (I) and [Ni(HL)₂(N₃)₂)] · 0.25H₂O (II) have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination. The crystal of I is orthorhombic: space group Pbca, a = 13.6928(9), b = 9.7203(6), c = 22.926(1) Å, V = 3051.4(3) Å^{3, Z} = 4. The crystal of II is triclinic: space group $P\bar 1$ , a} = 8.0212(7), b = 12.744(1), c = 15.590(2) Å, α = 104.802(3)°, β = 90.561(3)°, γ = 103.130(3)°, V = 1496.6(2) Å^{3, Z} = 1. The zwitterionic Schiff base ligands coordinate to the metal atoms through phenolate O, imine N, and amine N atoms. Each metal atom in the complexes is in octahedral coordination. The effect of these complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were studied.     

The crystal structures and electrochemical studies of two naphthalenic Schiff base copper(II) complexes

The Schiff base ligands, 2-hydroxy-N-cyclohexyl-l-naphthaldimine (I), and 3-hydroxy-N-cyclohexyl-2-naphthaldimine (II), and their corresponding Cu^II complexes (1–2) respectively were synthesized and characterized. The crystal and molecular structures of bis-{(cyclohexyl)[(2-oxo-1H-naphth-1-ylidene)-methyl]aminato}copper(II) (1) and bis-{(cyclohexyl)[(3-oxo-2H-naphth-2-ylidene)-methyl]aminato} copper(II) (2), were determined. The X-ray diffraction study shows that the geometry around the metal atom for (1), is stepped square planar with a step of 1.063 Å while for (2), the geometry around the metal atom for square planar with an angle between the coordination planes O(1)---Cu---N(1) and O(1a)---Cu---N(1a) of 39.9°. Electrochemical studies show a dependence of the Cu^II/Cu^I potentials on the ligand structure.     

Synthesis and crystal structures of two new Schiff base cobalt(II) and nickel(II) complexes

The Schiff base ligand (HL) obtained from phenylmethanamine and 5-methoxysalicylaldehyde are used as ligands for Co(II) and Ni(II) resulting in complexes [Co(L)₂] (I) and [Ni(L)₂] (II), and their solid state structures were determined by X-ray crystallography. In both complexes, weak interactions play an important role in the molecular self-assembly. Complex I was stacked up to the 2D layers by C-H…O hydrogen bonds and C-H…π interactions. In contrast, complex II was extended into 2D sheet by C-H…O hydrogen bonds, the C-H…π interactions, and edge-to-face interactions.     

Synthesis, characterization, and X-ray crystal structures of copper(II) and nickel(II) complexes with Schiff base

New copper(II) complexes, [Cu₂L¹L²] · ClO₄ (I) and [Ni(L³)₂] (II), where L¹ is the monoanionic form of 2-[1-(2-emthylaminoethylimino)ethyl]phenol, L² is the dianionic form of N,N′-ethylene-bis(2-hydroxyacetophenonylideneimine), L³ is the mono-anionic form of 2-(1-iminoethyl)phenol, were prepared and characterized using elemental analysis, FT-IR spectroscopy, and X-ray single-crystal diffraction. In complex I, the Cu(1) atom is coordinated by the NNO tridentate ligand L¹ and the two phenolate O atoms of L², forming a square pyramidal geometry. The Cu(2) atom in complex I is coordinated by the NNOO tetradenate ligand L², forming a square planar geometry. The Ni atom in complex II is coordinated by two phenolate O and two imine N atoms from two ligands L³, forming a square planar geometry. In the crystal structure of I, the perchlorate anions are linked to the dinuclear copper(II) complex cations through intermolecular N-H...O hydrogen bonds. In the crystal structure of II, the mononuclear nickel complex molecules are linked through intermolecular N-H...O hydrogen bonds, forming a trimer.     

Crystal structure of 4,4-bipyridine-containing complexes of copper(II) nitrate with 1-[(2-Hydroxyethylimino)methyl]naphthalen-2-ol and 2-[(2-hydroxyethylimino)methyl]phenol

The crystal structures of (μ-4,4-bipyridine)-di(nitrato-1-[(2-hydroxyethylimino)methyl]naphthalen-2-olocopper (I) and catena-di(μ-4,4’-bipyridine)di(μ-4,4’-bipyridine)-di(nitrato-2-[2-(hydroxyethylimino) methyl]phenolocopper)diaquacopper(II) nitrate (II) were determined. In the crystal of I, each of the two copper atoms coordinates a singly deprotonated tridentate azomethine molecule, a nitrate ion, and bipyridine, which functions as a bridge between the central atoms. The copper coordination polyhedron is a slightly distorted tetragonal pyramid with the base formed by the imine and bipyridine nitrogen atoms and the phenol and alcohol oxygen atoms. The axial site in the pyramid is occupied by the oxygen atom of the monodentate nitrate groups. In the trinuclear structure II with C₂ crystal chemical symmetry, the terminal coordination unit is composed through copper coordination of monodeprotonated 2-[2-(hydroxyethylimino)methyl]phenol, bipyridine, and the nitrate anion. In the crystal, the trinuclear molecules form infinite ribbons along the z axis in which the pyridine molecules perform the bridging function. The central copper atom has an octahedral configuration formed by the nitrogen atoms of four 4,4’-bipyridine molecules and oxygen of two water molecules.     

Synthesis,crystal structure and characterization of two new copper(II) complexes of Schiff bases derived from furfurylamine

Two new mononuclear complexes of copper(II), namely [CuL₂] (1) and [CuL′₂] (2) have been synthesized by reacting copper perchlorate with furfurylamine and salicylaldehyde or 2-hydroxyacetophenone, where L = (2-hydroxybenzyl-2-furylmethyl)imine and L′ = (2-hydroxymethylbenzyl-2-furylmethyl)imine, the respective asymmetric bidentate Schiff bases that are formed in situ to bind the Cu(II) ion. The complexes have been characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction studies. Structural studies reveal that the mononuclear units of both the complexes (1) and (2) adopt square planar geometry supported by weak intermolecular C–H···π interactions.