Synthesis and crystal structures of schiff base copper(II) complexes [Cu(L1)(NCS)], [CuBr(L2)], and [CuCl(L3)]

A series of copper(II) complexes, [Cu(L¹)(NCS)] (I), [CuBr(L²)] (II), and [CuCl(L³)] (III), where L¹, L², and L³ are 2,4-dibromo-6-[(pyridin-2-ylmethylimino)methyl]phenolate, 4-chloro-2-[(pyridin-2-ylmethylimino)methyl]phenolate, and 1-[(pyridin-2-ylmethylimino)methyl]-naphthalen-2-ol, respectively, were prepared. The complexes were characterized by elemental analysis, IR spectra, and single crystal X-ray determination. The crystals of the three complexes crystalize in the monoclinic space group P2₁/n. For I, a = 8.127(2), b = 13.077(3), c = 14.967(3) Å, β = 91.975(2)°, V = 1589.8(6) ų, Z = 4. For II, a = 7.736(2), b = 10.613(2), c = 16.199(3) Å, β = 91.130(2)°, V = 1329.8(5) ų, Z = 4. For III, a = 8.062(2), b = 8.599(2), c = 21.087(2) Å, β = 100.338(2)°, V = 1438.1(4) ų, Z = 4. The Cu atom in each of the complexes is in square planar geometry.     

A study of the structure and properties of mixed-ligand Cu(II) complexes with hexafluoroacetylacetone and methyl-, phenyl-ketoimines

The synthesis and X-ray single crystal study of two mixed-ligand Cu(II) complexes are performed: (CH₃C(NCH₃)CHC(O)CH₃)(CF₃C(O)CHC(O)CF₃)Cu (1) (space group P2₁/c, a = 7.0848(12) Å, b = 17.854(3) Å, c = 11.837(2) Å, β = 100.495(6)°, V = 1472.4(4) ų, Z = 4), (CH₃C(NC₆H₅)CHC(O)CH₃)· (CF₃C(O)CHC(O)CF₃)Cu (2) (space group P-1, a = 9.1119(4) Å, b = 9.6954(4) Å, c = 11.1447(6) Å, α = 113.784(2)°, β = 92.383(2)°, γ = 95.402(2)°, V = 893.52(7) ų, Z = 2). The structures are molecular, formed from neutral mixed-ligand copper complexes. The central copper atom has the (3O+N) coordination environment with average Cu-O distances of 1.948 Å and Cu-N of 1.932 Å; the chelate O-Cu-N angle (average) is 94.0°. In the structures, the complexes are linked into dimeric associates with Cu…Cu distances of 3.197 Å (for 1) and 3.246 Å (for 2). The volatility of mixed-ligand complexes 1 and 2 is in between of that of the starting homo-ligand complexes.     

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.     

Structure and characterization of A 2D cobalt(II) complex [Co(L)2] n (L = 3-nitro-5-(pyridine-4-yl)benzoate)

The self-assembly of unsymmetrical tecton 3-nitro-5-(pyridin-4-yl)benzoic acid (HL)with cobalt chloride under hydrothermal conditions affords a new 2D coordination polymer [Co(L)₂] _n (1, L = 3-nitro-5-(pyridin-4-yl)benzoate), which is characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, powder X-ray diffraction analysis, and single crystal X-ray diffraction. Compound 1 is of the triclinic system, space group P-1 with a = 9.7857(12) Å, b = 10.3417(13) Å, c = 10.8463(13) Å, α = 85.155(2)°, β = 74.785(2)°, γ = 88.962(2)°, V = 1055.4(2) ų. The crystal structural analysis of complex 1 shows that the cobalt center is six-coordinated in an octahedral geometry by four O atoms from four different L ligands and two N atoms from two different L ligands; the Co(II) cations are bridged by μ₃-L into an interesting two-dimensional network structure. It should be pointed out that the thermal analysis results indicate that complex 1 is quite stable up to 420°C.     

Synthesis and crystal structures of two Schiff base copper(II) complexes derived from 4-chloro-2-[(2-morpholin-4-ylethylimino)methyl]phenol

A centrosymmetric mononuclear copper(II) complex, [Cu(L¹)₂] (I), and a phenolate oxygen-bridged dinuclear copper(II) complex, [Cu₂(L²)₄] (II) (HL¹ = 4-chloro-2-[(2-morpholin-4-ylethylimino)methyl]phenol, HL² = 4-chloro-2-(cyclohexylimino-methyl)phenol), were synthesized and characterized by elemental analyses, IR, and single crystal X-ray diffraction. The crystal of I is monoclinic: space group {ITP}2₁/n, a = 13.396(3), b = 5.339(1), c = 19.740(4) Å, β = 108.64(3), V = 1337.8(5) ų, {ITZ} = 2. The crystal of II is monoclinic: space group P2₁, a = 9.157(2), b = 22.715(4), c = 12.169(2) Å, = 95.28(3), {ITV} = 2520.4(8) Å3, {ITZ}= 2. The Cu atom in I, lying on the inversion center, is four-coordinate in a square planar geometry with two phenolate oxygen and two imine nitrogen atoms. Each Cu atom in II is five-coordinate in a square pyramidal geometry with two phenolate oxygen and two imine nitrogen atoms from two L² ligands defining the basal plane and with one phenolate oxygen atom of another L² ligand occupying the apical position.     

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.     

Syntheses, crystal structures, and fluorescence properties of Zinc(II) complexes with multi-dentate Schiff bases

Two new structurally similar mononuclear Schiff base zinc(II) complexes, [ZnBr(ClMP)] (I) and [ZnCl(NMP)] (II) (ClMP = 4-chloro-2-[(3-morpholin-4-ylpropylimino)methyl]phenolate; NMP = 4-nitro-2-[(3-morpholin-4-ylpropylimino)methyl]phenolate), and two new dinuclear Schiff base zinc(II) complexes, [Zn₂(EMP)₂I₂] (III), and [Zn₂(MPA)(CH₃OH)₂(N₃)₂] (IV) (EMP = 5-diethylamino-2-[(2-dimethylaminoethylimino)methyl]phenolate; MPA = N,N′-bis(3-methoxysalicylidene)propane-1,3-diamine), have been prepared and characterized mainly by single-cyrstal X-ray diffraction. Complex I crystallizes in the monoclinic space group P2₁/n with unit cell dimensions: a = 15.116(3), b = 9.465(1), c = 23.714(4) Å, β = 104.358(2)°, V = 3286.9(8) ų, Z = 8, R ₁ = 0.0439, and wR ₂ = 0.0736. Complex II crystallizes in the monoclinic space group P2₁/c with unit cell dimensions: a = 7.253(2), b = 16.652(4), c = 13.568(3) Å, β = 96.600(2)°, V = 1627.8(6) ų, Z = 4, R ₁ = 0.0417, and wR ₂ = 0.0809. Complex III crystallizes in the monoclinic space group C2/c with unit cell dimensions: a = 27.962(2), b = 8.246(2), c = 31.605(3) Å, β = 90.343(2)°, V = 7287.4(15) ų, Z = 8, R ₁ = 0.0721, and wR ₂ = 0.1709. Complex IV crystallizes in the monoclinic space group C2/c with unit cell dimensions: a = 20.483(3), b = 11.344(2), c = 14.909(3) Å, β = 131.650(1)°, V = 2588.6(7) ų, Z = 4, R ₁ = 0.0343, and wR ₂ = 0.0792. Each Zn atom in I and II are four-coordinated in a tetrahedral geometry by the NNO donor set of the Schiff base ligand and one halide atom. The Zn atoms in III are in square pyramidal coordination, and those in IV are in octahedral and tetrahedral coordination. Thermal stability and fluorescence properties of the complexes I and II have also been determined.     

Crystal and molecular structures of bis(2,2,6,6-tetramethyl-3-methylaminoheptan-5-onate) copper(II) and nickel(II)

Two bis-chelates M(tmih)₂ (M = Cu(II), Ni(II), tmih = (CH₃)₃C(NCH₃)CHCOC(CH₃)₃)^? are synthesized and their crystal structures are determined using XRD (Bruker APEX-II diffractometer with a CCD detector, λMoK _α, λCuK _α, graphite monochromator, T = 240(2) K and 296(2) K): Cu(tmih)₂ (I) (space group P2₁/c, a = 12.9670(8) Å, b = 18.4921(9) Å, c = 11.0422(6) Å, β = 93.408(4)°, V = 2643.1(3) ų, Z = 4) and Ni(tmih)₂ (II) (space group P2₁/c, a = 12.810(2) Å, b = 18.529(2) Å, c = 11.243(2) Å, β = 91.959(7)°, V = 2667.1(6) ų, Z = 4). The complexes are isostructural; the coordination polyhedron of metal atoms is a flattened tetrahedron formed from two O atoms (Cu-O of 1.901(2) Å, 1.892(2) Å, Ni-O of 1.845(2) Å, 1.833(2) Å) and two N atoms (Cu-N of 1.976(3) Å, 1.972(3) Å, Ni-N of 1.911(2) Å, 1.920(2) Å) of the ligand; the chelate OMN angles (M = Cu(II), Ni(II)) are in the 87.4–93.1° range; the OMO and NMN angles are 162.2° and 167.2° in I, 171.1° and 173.2° in II. The complexes have the molecular structures formed from isolated molecules bonded by van der Waals interactions. Using a quantum chemical hybrid M06 method, the structures of copper(II) chelates with the H, CH₃, CH₂CH₃, CH(CH₃)₂, and C(CH₃)₃ substituents at the nitrogen atom are calculated. Found that with a bulky substituent at the nitrogen atom, the formation of chelates is hindered due to the intraligand repulsion between the atoms of this substituent and the tert-butyl group.     

Synthesis, structures, and antimicrobial activity of nickel(II) and zinc(II) complexes with Schiff bases derived from 3-bromosalicylaldehyde

The Schiff bases 2-bromo-6-[(3-cyclohexylaminopropylimino)methyl]phenol (HCMP) and 2-bromo-6-[(3-dimethylaminopropylimino)methyl]phenol (HDMP) derived from 3-bromosalicylaldehyde with N-cyclohexylpropane-1,3-diamine and N,N-dimethylpropane-1,3-diamine, respectively, and their nickel(II) and zinc(II) complexes [Ni(CMP)₂] (I) and [ZnCl₂(HDMP)] (II) have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination. The crystal of I is monoclinic: space group P2₁/c, a = 12.0304(6), b = 13.1594(6), c = 10.2445(5) Å, β = 101.019(1)°, V = 1591.9(1) ų, Z = 2. The crystal of II is monoclinic: space group C2/c, a = 22.286(5), b = 12.210(3), c = 14.513(3) Å, β = 124.118(3)°, V = 3269.5(13) ų, Z = 8. The Schiff base HCMP coordinates to the Ni atom through the phenolate O, imine N, and amine N atoms, while the Schiff base HDMP coordinates to the Zn atom through the phenolate O and imine N atoms. The effect of these complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were studied.     

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, 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.     

Copper(II)-assisted thorough hydrolysis of 2,4,6-tris(2-pyridyl)1,3,5-triazine (tptz). Crystal structures of bis(2-pyridylcarboxylato)-copper(II) dihydrate and bis(2-pyridylcarbonyl)-amido-2,4,6-tris(2-pyridyl)-1,3,5-triazine-copper(II) dicyanamide heptahydrate

2,4,6-Tris(2-pyridyl)-1,3,5-triazine (tptz) undergoes hydrolysis in the presence of copper(II) acetate affording bis(2-pyridylcarbonyl)amido-copper(II) and free 2-pyridylcarboxylic anion. Two compounds of formulas [Cu(NC₅H₄COO)₂]·2H₂O (1) and [Cu(NC₅H₄CO)₂N(tptz)](N(CN)₂)·7H₂O (2), where NC₅H₄COO^? and (NC₅H₄CO)₂N^? are 2-pyridylcarboxylate and bis(2-pyridylcarbonyl)amido-anion, respectively, were obtained from methanol/ethanol solution of tptz with copper acetate; they were characterized by element analysis and single crystal X-ray diffraction method. Single crystal XRD analysis shows that in complex 1 coordination number around Cu atom is 4 with distorted square-planar coordination geometry and in complex 2 coordination number around Cu atom is 6 with distorted octahedral geometry. Crystal data for 1: a = 5.1359(10) Å, b = 7.6471(15) Å, c = 9.2303(18) Å, α = 74.90(3)°, β = 84.36(3)°, γ = 71.37(3)°, space group P1, crystal system triclinic, Z = 1, V = 331.6(1) ų, d _calc = 1.721 g/cm³. Crystallographic data for 2: space group C2/c, crystal system monoclinic, a = 23.976(5) Å, b = 15.465(3) Å, c = 18.649(4) Å, β = 92.66(3)°, V = 6907(2) ų, d _calc = 1.0448 g/cm³, Z = 4.     

Heteroligand zinc(II) and copper(II) complexes with naphthylacetic acid and monoethanolamine: Syntheses and crystal structures

New heteroligand Cu(II) and Zn(II) complexes with the α-naphthylacetic acid anion (NAA) and monoethanolamine (MEA), [M(NAA)₂(MEA)₂] (M = Cu²⁺, (I), Zn²⁺ (II)), are synthesized. The crystal structures of the obtained complexes are determined by X-ray diffraction analysis (CIF files CCDC 984097 (I) and 930946 (II)). The crystals are monoclinic, for I: a = 18.8140(9) Å, b = 4.82500(14) Å, c = 16.0360(7) Å, β = 115.135(6)°, V = 1317.87(11) ų, space group P2₁/c, Z = 2; for II: a = 32.9760(14) Å, b = 5.0911(3) Å, c = 15.7994(10) Å, β = 94.418(5)°, V = 2644.6(3) ų, space group C2/c, Z = 4. In the structure of complex I, the Cu²⁺ ion arranged in the symmetry center is coordinated at the vertices of the distorted octahedron by the oxygen atoms of two NAA molecules (Cu-O(2) 2.019(4) Å) and two MEA molecules. The latter is the bidentate-chelating ligand and coordinates the metal through the O and N atoms to form the five-membered metallocycle (Cu-O(3) 2.457(5), Cu-N(1) 1.986(5) Å). In complex II, the Zn atom (on axis 2) is coordinated at the vertices of the distorted tetrahedron by the oxygen atoms of two NAA molecules (Zn-O(2) 1.976(4) Å) and the nitrogen atoms of two MEA molecules (Zn-N 2.034(6) Å). The character of the interaction of coordinated NAA and MEA ligands and methods for packing complexes I and II are considered on the basis of the structural data.     

Synthesis and crystal structures of two azido-bridged copper(II) complexes with schiff bases

Two new end-on azido-bridged dinuclear copper(II) complexes with the formula [Cu(μ_1,1-N₃)₂(IEP)₂] (I) and [Cu(μ_1,1-N₃)₂(EMP)₂] (II), where IEP and EMP are the deprotonated forms of 2-[1-(2-isopropylaminoethylimino)ethyl]phenol and 2-ethoxy-6-[(2-methylaminoeth-ylimino)methyl]phenol, respectively, were synthesized. Both complexes were characterized by elemental analyses and IR spectra. The crystal structures were determined by the X-ray diffraction. The crystal of I is monoclinic: space group P2₁/c, a = 9.662(2), b = 15.282(3), c = 10.639(2) Å, β = 115.418(10)°, V = 1418.9(5) ų, Z = 2. The crystal of II is monoclinic: space group P2₁/n, a = 12.588(2), b = 7.705(1), c = 14.481(2), β = 91.736(5)°, V = 1403.9(2) ų, Z = 2. The two Cu atoms in each complex are bridged by two end-on azide groups. Each Cu atom is in a square pyramidal coordination. The Cu…Cu distances are 3.230(2) Å in I and 3.150(2) Å in II.     

Synthesis and crystal structure of the copper(II) valerate complex with nicotinamide

A coordination compound of copper(II) valerate with nicotinamide, [CuL(C₄H₉COO)₂]₂ (I), has been synthesized, and its crystal structure has been determined by X-ray crystallography. The crystals of I are triclinic: a = 9.1245(9) Å, b = 9.8572(6) Å, c = 11.0944(9) Å, α = 73.51(1)°, β = 79.917(6)°, γ = 72.161(7)°, Z = 2, space group $P\bar 1$ . In the centrosymmetric binuclear molecule of I, the copper atoms (Cu...Cu′, 2.621 Å) are linked through four bidentate chelating valerate ligands (av., Cu-O 1.969 Å). The coordination polyhedron of the Cu atom is a tetragonal pyramid with the nitrogen atom of the pyridine ring in the apical position at a longer distance (Cu-N, 2.190 Å).     

Synthesis, structures, and antimicrobial activity of nickel(II) and Zinc(II) complexes with 5-methoxy-2-[(3-methylaminopropylimino)methyl]phenol

The Schiff base 5-methoxy-2-[(3-methylaminopropylimino)methyl]phenol (MMP) derived from 4-methoxysalicylaldehyde and N-methylpropane-1,3-diamine and its nickel(II) and zinc(II) complexes [Ni(MMP)₂(NCS)₂] (I) and [ZnCl₂(MMP)] (II), have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination. The crystal of I is monoclinic: space group P2₁/c, a = 9.0488(8), b = 12.7768(12), c = 12.9232(11) Å, β = 101.927(5)°, V = 1461.9(2) ų, Z = 2. The crystal of II is orthorhombic: space group Pbca, a = 11.6991(7), b = 13.2839(8), c = 20.4451(12) Å, V = 3177.4(3) ų, Z = 8. The Schiff base coordinates to the metal atoms through the phenolate O and imine N atoms. The effect of these complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were studied.     

Reaction of copper(II) cysteinate with thiosemicarbazide: Crystal structure of a complex of copper(II) thiocyanate with thiosemicarbazide

The reaction of copper(II) cysteinate with thiosemicarbazide (TSC) in water was found to yield complex of copper(II) thiocyanate of the [Cu(TSC)₂(SCN)₂] composition, whose crystal structure was determined by X-ray crystallography. Crystals of the complex are triclinic with a = 6.040 Å, b = 7.112 Å, c = 8.276 Å, α = 91.34°, β = 101.72°, Γ = 114.83°, Z = 2, space group \(P\bar 1\). Structural units of the complex are [Cu(TSC)₂]²⁺ centrosymmetric cations and (SCN)^? anions linked by hydrogen bonds (HB), as well as by electrostatic and π-π stacking interactions. The coordination polyhedron of Cu atoms is a square completed to bipyramid; the bonds Cu(1)-N(3), Cu(1)-S(1), and Cu(1)-S(2) are 2.002 Å, 2.303 Å, and 3.015 Å, respectively.     

Acid Co(II) and Ni(II) trifluoroacetate complexes: Synthesis and crystal structure

Anhydrous and partially hydrated acid trinuclear trifluoroacetates of divalent transition metals of the composition [M₃(CF₃COO)₆(CF₃COOH)₆)](CF₃COOH) and [M₃(CF₃COO)₆(CF₃COOH)₂(H₂O)₄)](CF₃COOH)₂, respectively, where M = Co (I, III) Ni (II, IV), were synthesized and studied by X-ray diffraction. Complexes I and II were obtained by crystallization from solutions of M(CF₃COO)₂ · 4H₂O in trifluoroacetic anhydride; complexes III and IV were synthesized under the same conditions with the use of 99% trifluoroacetic acid as a solvent. Crystals I are triclinic: space group $P\bar 1$ , a = 13.199(6) Å, b = 14.649(6) Å, c = 15.818(6) Å, α = 90.04(4)°, β = 114.32(4)°, γ = 108.55(4)°, V = 2611.3(19) ų, Z = 2, R = 0.0480. Crystals II are trigonal: space group $R\bar 3$ , a = 13.307(2) Å, c = 53.13(1) Å, V = 8148(2) ų, Z = 6, R = 0.1112. Crystals III are triclinic: space group $P\bar 1$ , a = 9.001(8) Å, b = 10.379(9) Å, c = 12.119(9) Å, α = 83.67(5)°, β = 72.33(5)°, γ = 83.44(5)°, V = 1068.3(15) ų, Z = 1 Å, R = 0.1031. Crystals IV are triclinic: space group $P\bar 1$ , a = 9.121(18) Å, b = 10.379(2) Å, c = 12.109(2) Å, α = 84.59(3)°, β = 72.20(3)°, γ = 82.80(3)°, V = 1080.94(40) ų, Z = 1, R = 0.0334.     

Copper(I) halide complexes with ethylenediaminium L0(H+)2, N,N,N′,N′-tetraallylethylenediaminium L4(H+)2, and N,N,N,N′,N′-pentaallylethylenediaminium L5(H+). Synthesis and crystal structures of the complexes [L0(H+)2]0.5CuCl2, [L0(H+)2]0.5CuBr1.67Cl0.33, [{L4(H+)2}0.5Cu2Cl3], and [L5(H+)Cu4Br6]

Alkylation of ethylenediamine with allyl bromide in the presence of NaHCO₃ in benzene-ethanol and acetone-ethanol gave N,N,N′,N′-tetraallylethylenediamine L⁴ and N,N,N,N′,N′-pentaallylethylenediaminium bromide (L₅(H⁺)Br₂), respectively. The ac electrochemical synthesis at copper wire electrodes in solutions of copper(II) halide and an appropriate ligand yielded single crystals of Cu(I) complexes with ethylenediaminium ([L⁰(H⁺)₂]_0.5CuCl₂ (I) and [L⁰(H⁺)₂]_0.5CuBr_1.67Cl_0.33 (II)) and its N-allyl derivatives N,N,N′,N′-tetraallylethylenediaminium ([{L⁴(H⁺)₂}_0.5Cu₂Cl₃] (III)) and N,N,N,N′,N′-pentaallylethylenediaminium ([L⁵(H⁺)Cu₄Br₆] (IV)). The crystal structures of complexes I–IV were determined by X-ray diffraction. The isostructural crystals of complexes I and II are triclinic, space group P $ \bar 1 $ , Z = 2. For I: a = 5.936(3), b = 6.387(3), c = 7.126(4) Å, α = 67.82(4)°, β = 72.98(4)°, γ = 67.55(4)°, V = 227.7(2) ų. For II a = 6.110(3), b = 6.657(3), c = 7.309(3) Å, α = 68.40(3)°, β = 72.38(3)°, γ = 67.23(3)°, V = 250.4(2) ų. In structures I and II, the organic cations are between infinite anionic chains (Cu ₂ ^? ) _n . The crystals of π-complex III are triclinic, space group P $ \bar 1 $ , a = 6.851(4), b = 8.729(4), c = 9.960(4) Å, α = 98.25(3)°, β = 102.29(3)°, γ = 107.30(3)°, V = 541.8(5) ų, Z = 2. In structure III, all the four allyl groups are π-coordinated by the metal atoms of four discrete anions Cu₄Cl ₆ ^2? . The crystals of π-complex IV are monoclinic, space group C2/c, a = 15.228(5), b = 17.095(6), c = 20.182(6) Å, β = 92.43(4)°, V = 5249(3) ų, Z = 8. Only two of five allyl groups at the same N atom are coordinated by copper(I) atoms. Structure IV contains a complex inorganic fragment of the formula (Cu₄Br ₆ ^2? ) _n .     

Synthesis and X-ray crystal structures of two cobalt(III) complexes with Schiff bases

Two new mononuclear cobalt(III) complexes, [Co(MP)₂(N₃)] (I) and [Co(BP)₂]NO₃ · 2H₂O (II), where MP is 2-methoxy-6-[(2-morpholin-4-ylethylimino)methyl]phenolate and BP is 4-bromo-2-[(2-methylaminoethylimino)methyl]phenolate, were prepared and structurally characterized by physicochemical methods and single crystal X-ray diffraction. Both complexes crystallize in the monoclinic space group P2₁/c. For I: a = 10.3526(18), b = 25.371(4), c = 11.3585(19) Å, β = 101.529(8)°, V = 2923.1(8) ų, Z = 4; for II: a = 9.801(2), b = 27.183(3), c = 10.846(2) Å, β = 114.269(2)°, V = 2634.2(8) ų, Z = 4. An X-ray structural analysis indicates that in both complexes the Co atoms adopt octahedral coordination. The hindrance effects of the Schiff bases can influence the coordination of the secondary ligands such as azide.