Synthesis and structural characterization of the dinuclear tetrakis(guanidino) bis(2-cyanoguanidine)dicopper(II) complex

The synthesis and crystal structure of a new dinuclear complex Cu₂(C₂H₄N₄)₂ (CH₃N₃)₄ are reported. It crystallizes in the monoclinic system of space group P2₁/c, with a = 8,459(1) Å, b = 15,481(3) Å, c = 8,714(2) Å, = 110,60(1)°, and Z = 2. The centrosymmetric molecular structure of Cu₂(C₂H₄N₄)₂(CH₃N₃)₄ comprises a tetrakis(guanidino)-bridged dinuclear copper(II) core with axially located cnge moities.     

Structural and spectroscopic characterization of tris (o-phenanthroline)iron(II) disaccharinate monosaccharin hexahydrate

The crystal and molecular structure of the title compound, for short [Fe(o-phen)₃](sac)₂·(Hsac)·6H₂O, has been determined by X-ray diffraction methods. It crystallizes in the monoclinic space group P2₁/n with a = 16.3190(1), b = 19.2890(1), c = 17.4490(2) Å, = 92.586(1)°, V = 5486.95(8) ų and, Z = 4. The investigated compound constitutes the first example of a species in which uncoordinated saccharin and saccharinate anions are present in the structure. The crystallographic results reveal the subtle differences between the structure of the neutral molecule and its anion. The complex was also characterized by means of infrared, electronic, and ⁵⁷Fe-Mössbauer spectroscopy. Its magnetic susceptibility was determined at room temperature and its thermal behavior investigated by means of thermogravimetric and differential thermal analytical techniques.     

Synthesis and crystal structure of a cobalt(II) complex with tris(1-pyrazolylmethyl)amine

The synthesis of a cobalt(II) complex of tris(1-pyrazolylmethyl)amine (amtp) is reported. The complex [Co(amtp)Cl](BPh₄) crystallizes in the space group P-1, with a = 8.979(2), b = 19.329(3), c = 20.251(3) Å, = 93.321(2), = 93.685(3), = 98.930(2)°, and Z = 4. The Co(II) atom is nearly tetrahedrally coordinated by three pyrazole N-atoms and one Cl^–. The tertiary amine N-atom of amtp is only weakly coordinated to Co(II) atom at a Co—N(amine) distance of ca 2.40 Å.     

Synthesis and structural characterization of the dinuclear bis(glutarato)bis(urea)copper(II)complex, dihydrate

The complex [Cu(OOC-(CH₂)₃-COO)(O=C(NH₂)₂]₂·2H₂O has been synthesized and characterized by X-ray crystallography. It crystallizes in the triclinic system P-1 with a = 8.003(2) ?, b = 8.611(2) ?, c = 8.620(2) ?, α = 96.14(3)°, β = 116.66(2)°, γ = 105.66(4)° and V = 492.9(3) ?³. The structure consists of discrete centrosymmetric binuclear units and water molecules. The Cu(II) ions adopt a square-pyramidal coordination with four oxygen atoms of four bridging carboxylate and one carbonyl oxygen of the monodentate urea ligand. There is a very strong interaction between the two copper centers in binuclear entities (CuCu: 2.6266(15) ?).     

Synthesis and Crystal Structure of a Polymeric Cobalt(II) Complex with 1,2-bis(1,2,4-triazol-1-yl)ethane

Abstract The title complex [Co₂(bte)₃(NCS)₄(H₂O)₂] _n (bte = 1,2-bis(triazol-1-yl)ethane) has been prepared. Single-crystal X-ray analysis reveals that the complex crystallizes in space group P ī with a = 7.7962(2), b = 8.3407(4), c = 14.7735(5) ?, α = 86.835(2), β = 76.2031(9), γ = 80.583(3)°. The crystal consists of two discrete complexes, [Co(bte)(NCS)₂(H₂O)₂] and [Co(bte)₂(NCS)₂]. The structure of [Co(bte)(NCS)₂(H₂O)₂] consists of neutral chain containing Co(II) bridged by bte molecules. The six-co-ordination of Co²⁺ is achieved by means of two trans NCS⁻ ions and water molecules. The structure of [Co(bte)₂(NCS)₂] demonstrates a one-dimensional neutral chain through bte-bridge, in which the Co(II) atom is in a distorted octahedral environment formed by four nitrogen atoms of the triazoles and two nitrogen atoms from two trans thiocyanato liagnds. Index abstract Synthesis and Crystal Structure of a Polymeric Cobalt(II) Complex with 1,2-bis(1,2,4-triazol-1-yl)ethane This paper reports the synthesis and crystal structure of complex [Co₂(bte)₃(NCS)₄(H₂O)₂]_n (bte = 1,2-bis(triazol-1-yl)ethane), which consists two different neutral chains containing Co(II) bridged by bte molecules.      

Synthesis and characterization of copper(II) hexaazamacrotetracyclic complex with thiocynate ligand

A mononuclear complex [Cu(L)(NCS)](ClO₄) (1) (L = 1,3,10,12,16,19-hexaazatetracyclo [17,3,1, 1^12.16,0^4.9]tetracosane) has been synthesized and structurally characterized by X-ray crystal structure analysis. The crystals are monoclinic P2₁2₁2₁ with a = 9.596(1), b = 11.285(1), c = 22.446(2) Å, V = 2430.7(3) ų, Z = 4. The copper atom is coordinated by two secondary and two tertiary amines of the macrocycle and one nitrogen atom of the thiocynate ligand in a distorted square-pyramidal geometry. The cyclic voltammogram of 1 exhibits two waves of a one-electron transfer corresponding to Cu^II/Cu^III and Cu^II/Cu^I processes.     

Synthetic and structural studies of the trans bis(2-N-H-pyrrolylcarbaldimine) complexes of nickel(II) and palladium(II)

The molecular bis(2-N-H-pyrrolylcarbaldimine)nickel(II) and palladium(II) complexes are isolated in moderate yield (30–35%) from in situ assembly of the Schiff base with metal(II) salt, base, and pyrrole-2-carbaldehyde in aqueous ammonia solution. The nickel(II) complex, 1, is monoclinic, space group P2₁/c, with a=11.289(6) ?, b=5.611(3) ?, c=8.287(5) ?, β=111.620(6)°, and V=488.0(5) ?³ with Z=2, for d _calc=1.667 Mg/m³. The palladium analog, 2, is isomorphous, space group P2₁/c, with a=11.481(3) ?, b=5.5738(10) ?, c=8.276(2) ?, β=110.923(12)°, and V=494.7(2) ?³ with Z=2, for d _calc=1.965 Mg/m³. In both crystal structures, the metal resides on an inversion center. In the IR spectra, ν(C=N) appears at 1561 cm⁻¹ in 1, and 1557 cm⁻¹ in 2, while ν(N–H) shows at 3345 cm⁻¹ and 3335 cm⁻¹, respectively. The ¹H-nmr spectra reveal the C–H and N–H protons of the imine group as sharp and broad doublets, respectively, at 7.62 and 8.38 δ in 1 and at 7.92 and 9.73 δ in 2.     

Synthesis, Crystal Structure of a New Co(II) Complex with Pyrazine-2,3,5,6-tetracarboxylic Acid

Abstract A new complex [Co(H₂pztc)(bpy)H₂O] (H₄pztc = pyrazine-2,3,5,6-tetracarboxylic acid, bpy = 2,2′-bipyridine) has been synthesized by hydrothermal reactions of Co(NO₃)₂ · 6H₂O with H₄pztc and bpy and characterized by IR and X-ray diffraction single crystal structure analysis. It belongs to monoclinic system, P2₁/c space group with a = 13.454(2) ?, b = 12.939(2) ?, c = 11.4993(19) ?, α = 90°, β = 111.640(3)°, γ = 90°. This complex is assembled into 3D supramolecular architecture by hydrogen bonds (O–H···O, C–H···O). Index Abstract A new complex of cobalt(II) with pyrazine-2,3,5,6-tetracarboxylic acid and 2,2′-bipyridine is assembled by intermolecular hydrogen bonds forming 2D layer and 3D supramolecular network.      

Synthesis and structure of a hexaazamacrocyclic copper(II) complex with maleato ligand

A hexaazamacrocyclic copper(II) complex Cu(L)(H₂O) (O₂CCH = CHCO₂)⋅H₂O (1) (L = 3,10-bis(2-hydroxyethyl)-1,3,5,8,10,12-hexaazacyclotetradecane) was prepared and structurally characterized by a combination of analytical, spectroscopic, and crystallographic methods. In complex 1, the coordination geometry about the copper(II) ion is six-coordinate with four equatorial nitrogen atoms from the macrocycle and two oxygen atoms from the axial maleato and aqua ligands. In 1, the one end of the maleato ligand coordinates to the central copper atom, while the other end is not bonded. The macrocycle and the axial ligands are highly involved in multiple types of hydrogen bonding interactions, resulting in the stabilization of the maleato ligand as a “coordinated ligand counter anion.”     

Synthesis and structural characterization of a novel polymeric gadolinium(III)–copper(II) complex of iminodiacetic acid

A novel polymeric Gd₂Cu₃ complex of iminodiacetic acid (H₂L¹=NH{CH₂COOH}₂), namely, Gd₂Cu₃(L¹)₆, 1, has been synthesized and structurally characterized. In the title complex, the Gd³⁺ ion is nine-coordinated by six O atoms from three bidentate chelating carboxylate groups and three O atoms from three anti-anti bridging carboxylic groups of six L¹ ligands; the Cu²⁺ ion is six-coordinated by four O and two N atoms from two chelating L¹ ligands. Each pair of Gd(III) atoms is bridged by three L¹ ligands, each of which also chelates with one copper(II) ion, thus forming a Gd₂Cu₃ cluster unit. Such cluster units are cross-linked by flexible L¹ ligands into a three-dimensional coordination framework. The title complex crystallizes in the trigonal space group P-3c1 (No. 165) with a = b = 13.433(4), c = 14.770(6) Å; V = 2308(1) ų; D_calca = 1.859 g cm^–3; Z = 2.     

Synthesis and X-ray characterization of a polymeric 1:3 complex of copper(II) nitrate with pyrazine

The structure of poly--pyrazine-bis(pyrazine)(dinitrato-O)copper(II), Cu(pyz)₃(NO₃)₂, has been investigated by X-ray diffraction. The compound crystallizes in the triclinic space group with a = 6.8040 (10), b = 7.2860 (10), c = 9.289 (2) Å, = 69.65 (2), = 68.51 (2), = 67.51 (2)°, and Z = 1. The structure consists of linear chains of copper ions bridged by bidentate pyrazine groups, with monodentate terminal pyrazine and nitrate groups completing the distorted octahedral geometry about the copper ions.     

Synthesis and Crystal Structure of a Mixed-Ligand Cobalt(II) Complex with 2-Aminobenzimidazole

Abstract  The cobalt(II) complex, [Co(abz)₂(SCN)₂] 1, has been synthesized by the reaction of cobalt(II) nitrate with ammonium thiocyanate and abz ligands (abz = 2-aminobenzimidazole), and was fully structurally characterized by elemental analysis, IR spectra, X-ray diffraction and thermogravimetric experiments. It crystallizes in the triclinic P-1 space group with a = 8.6316(10), b = 9.3426(10), c = 13.254(2) ?, α = 95.793(2), β = 95.870(2), γ = 115.7380(10), V = 945.1(2) ?³, and Z = 2. The central cobalt(II) atom is four-coordinated to nitrogen donors from two neutral abz ligands and two isothiocyanate anions respectively, adopting a slightly distorted tetrahedral geometry. In addition, the intermolecular N–H···N and N–H···S hydrogen bonds interactions link the discrete mononuclear units into infinite three-dimensional networks. Index Abstract  The essence sentence of the paper: In the mixed-ligand mononuclear complex, [Co(abz)₂(SCN)₂], the four coordinated cobalt(II) atom exhibits a slightly distort tetrahedron, which is further assembled into 3D infinite network by intermolecular hydrogen interactions.      

Synthesis and structure of bis(2,6-dimethylpyrazine)(THF)copper(II) nitrate

Attempts to crystallize Cu(2,6-dmpz)(NO₃)₂ (2,6-dmpz = 2,6-dimethylpyrazine) by reaction of 2,6-dmpz with Cu(NO₃)₂·3H₂O in THF resulted in the synthesis of Cu(2,6-dmpz)₂(NO₃)₂·THF. The compound crystallized in the monoclinic space group C2/c and exists as isolated molecules with distorted square pyramidal geometry: a = 11.609(4) Å, b = 10.415(3) Å, c = 18.256(6) Å, = 108.332(4)°. The 2,6-dmpz molecules coordinate to the Cu ions through the distal (remote from the methyl) nitrogens. The molecules are arrayed in stacks parallel to the b-axis.     

Synthesis,characterization and photoluminescence studies of new Cu(II) complex

In the current work, a new coordination complex, [Cu(HL)₂], 1 [H₂L = 2–((E)–(2–hydroxypropylimino)methyl)–4–nitrophenol] was successfully synthesized and characterized by IR, UV-vis and photoluminescence spectroscopic techniques, single crystal and powder X-ray diffraction measurements. In the crystalline structure of complex 1, the aliphatic –OH group of the ligand is not coordinated and points away from the metal coordination zone, and also actively participates in intermolecular bifurcated O?H···O hydrogen bonds which link the molecules to form hydrogen-bonded linear chains. C?H···π and π···π contacts also connect the molecules in the structure which form to 3D structure. This hydrogen bonded polymeric networks lie in the bc-plane and stacks along to the a-axis. Furthermore, complex 1 and its ligand H₂L display an intense navy-blue emission and blue emission in the solid state at room temperature, respectively, when they are excited under UV light.     

Synthesis and Structural Comparison for a Series of Cr(II) (iodo) NacNac Complexes

Abstract  A series of complexes of the form [bis(2,6-diisopropylphenyl)pentane-2,4-ketiminato](iodo)(solvent) chromium were synthesized and structurally characterized (solvent = tetrahydrofuran, acetonitrile, α-picoline). The tetrahydrofuran adduct crystallized in the P2₁/n space group with the crystal cell parameters a = 17.628(6) ?, b = 10.218(3) ?, c = 20.646(7) ?, β = 109.209(4)°, V = 3512(2) ?³ and Z = 4. The acetonitrile adduct crystallized in the P2₁/c space group with the crystal cell parameters a = 16.104(7) ?, b = 11.965(5) ?, c = 18.201(8) ?, β = 116.091(6)°, V = 3150(2) ?³ and Z = 4. The α-picoline adduct crystallized in the C2/c space group with the crystal cell parameters a = 39.982(9) ?, b = 11.637(2) ?, c = 16.560(4) ?, β = 108.085(4)°, V = 7325(3) ?³ and Z = 8. For each compound, the coordination around each chromium center is square planar with varying degrees of distortion. Graphical Abstract  A series of Cr(II) complexes of the form LCrI(S) (where L = nacnac = β-diketiminate; S = solvent) were synthesized and structurally characterized.      

Palladium(II) and platinum(II) tetrakisthiourea dichloride bis(7-hydroxy-5-methyl[1,2,4]triazolo[1,5a]pyrimidine) dihydrate solvates

The title compounds palladium(II) and platinum(II) tetrakisthiourea dichloride bis(7-hydroxy-5-methyl[1,2,4]triazolo[1,5a]pyrimidine (Hmtpo)) dihydrate solvates, have been synthesized by reacting thecis-[MCl₂(Hmtpo)₂] (where M=Pt(II), Pd(II)) complexes with an excess of thiourea (tu) and the structure of the palladium compound was solved by X-ray diffraction. Crystals of [Pd(tu)₄]Cl₂·2Hmtpo·2H₂O are triclinic with space groupP and unit cell dimensionsa=7.972(1),b=9.049(1),c=11.808(2)Å, =88.20(1), =75.15(1), =76.54(1)^o. The cation [Pd(tu)₄]²⁺ is centrosymmetric involving four sulfur thiourea atoms in a near square planar environment. The triazolopyrimidine molecules, chloride anions and water molecules do not take part in the metal center coordination but interact by hydrogen bonding between them and the thiourea moieties. A comparison between powder diffraction data of palladium(II) and platinum(II) compounds clearly indicates that both compounds are isomorphous.     

Self-assembly in transition metal complexes: structural characterization of a copper histamine nitrate [Cu(II)(him)2(NO3)2]

A new monomeric copper (II) complex with histamine (him), [Cu(II)(him)₂(No₃)₂], has been prepared by the reaction of Cu(NO₃)₂ with histaminium dichloride and its structure was determined by x-ray crystallography. The complex crystallizes in the triclinic system, space group with a = 5.7238(4), b = 8.7094(7), c = 9.2481(11) Å, = 69.693(8), = 73.242(7), = 71.050(7)°, V = 400.84(6) ų, and Z = 1. The structure consists of discrete [Cu(II)(him)₂(NO₃)₂] molecules in which the metal atom is centrosymmetrically coordinated by two histamine ligands forming an equatorial plane with Cu–N(imidazole ring) being 2.032(2) and Cu–N(NH₂ group) being 2.023(2) Å. Two O atoms from nitrate anions coordinate on the elongated axial positions with Cu–O being 2.549(2) Å. In the crystal structure, the molecules are organized by hydrogen bonds forming a two-dimensional network.     

Synthesis and characterization of carboxylate-bridged copper(II) dinuclear complex

The dinuclear copper(II) complex {[Cu(pmea)Cl][Cu(H₂O)₃Cl]}(Cl)·H₂O (1) (pmea =bis(2-pyridylmethyl)amino-2-ethanoic acid) has been synthesized and characterized. It crystallizes in the monoclinic system P2₁/c, a = 9.0057(11), b = 28.031(3), c = 8.5669(10) Å, β = 104.267(2)°, V = 2095.9(4) ų, Z = 4. Crystal structure of 1 reveals a syn-anti carboxylate-bridged dinuclear complex, in which the coordination environment around each copper atom exhibits a distorted square-pyramid. Magnetic susceptibility measurement for 1 exhibits a weak intermolecular antiferromagnetic exchange interaction with 2J = −1.17(9) cm⁻¹. The cyclic voltammogram of 1 gives one oxidation and two reduction processes.     

Synthesis and crystal structures of four nickel(II) 1,5-naphthalenedisulfonate compounds

Four nickle(II) 1,5-naphthalenedisulfonate (1,5nds) complexes, namely [Ni(H₂O)₆] (1,5nds) (1), trans-[Ni(en)₂(H₂O)₂](1,5nds)·2H₂O (2), [Ni(tren)(H₂O)₂](1,5nds)·H₂O (3), and [Ni(dien)₂](1,5nds)·2H₂O (4), where en = ethylenediamine, tren = tris(2-aminoethyl)amine, and dien = diethylenetriamine, have been synthesized and structurally characterized. Compound 1 crystallizes in space group P2₁/c, with a = 13.200(2) Å, b = 6.6197(10) Å, c = 9.6001(14) Å, and = 92.005(3)° compound 2 crystallizes in space group C2/c, with a = 15.698(2) Å, b = 13.006(2) Å, c = 12.845(2) Å, and = 119.262(4) Å compound 3 crystallizes in space group P , with a = 8.8971(10) Å, b = 11.5440(13) Å, c = 11.9169(14) Å, = 77.254(2)°, = 74.079(2)°, and = 82.162(2)° compound 4 crystallizes in space group P2₁/c, with a = 10.3600(13) Å, b = 12.5650(16) Å, c = 9.9853(12) Å, and = 103.599(2)°. Compound 1 crystallizes in a typical inorganic–organic layered structure adopted by metal naphthalenesulfonate, while compounds 2–4 crystallize in a hybrid inorganic–organic pattern. Unlike their Cu²⁺ analogue, the sulfonate does not coordinate directly to Ni²⁺. The hydrogen bonds formed between sulfonate and water molecules are the predominant packing forces for all structures. The inherited inversion center of the 1,5nds anion is carried into the crystal structure and results in centrosymmetric crystallization of all compounds.     

Synthesis and crystal structure of diaquatetra(5-methyl-1,2-oxazol-3-amine)iron(II) perchlorate

A new monomeric iron(II) complex of 5-methyl-1,2-oxazol-3-amine(moxa) has been synthesized and structurally characterized. Fe(II) atom is in a distorted octahedral environment with four ring N atoms of the oxazol and two water ligands. Complex molecules and uncoordinated oxazol ligands are linked together by hydrogen bonding. This complex is diamagnetic at different temperatures and no spin-crossover was observed. Magnetic susceptibility measurement was performed by Evans method in solution. IR and UV–vis spectrum of the complex was measured to investigate the solution behavior of the complex. The space group is P (No. 2), with a = 7.4137(2), b = 10.9395(3), c = 13.5284(3) Å, = 67.146(1), = 88.565(1), = 78.556(1)°, V = 989.31(4) ų, and Z = 1.