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.      

Synthesis and Structural Characterization of Bis[(cyclohexylamino)pent-2-en-4-onato]-Chromium(II)

Abstract  Addition of one equivalent of CrI₂ to two equivalents of lithium cyclohexylamino-pent-2-en-4-onate results in bis[(cyclohexylamino)pent-2-en-4-onato]-chromium(II). Crystallization in diethylether reaction solvent forms the hemi-etherate A with the asymmetric unit showing two target compounds and one molecule of cocrystallized diethylether in the P-1 space group with crystal cell parameters a = 12.931(4) Å, b = 13.207(4) Å, c = 16.104(5) Å, α = 66.559(5)°, β = 77.670(5)°, γ = 81.562(5)°, V = 2,459.1(14) Å³ and Z = 4. Drying A in vacuo and recrystallization in pentane yields a nonsolvated crystalline phase B with an asymmetric unit displaying only one molecule of the target compound in the P2₁/c space group with crystal cell parameters a = 14.290(7) Å, b = 14.082(7) Å, c = 11.246(6) Å, β = 94.807(8)°, V = 2,255.1(19) Å³ and Z = 4. Graphical Abstract  A Cr(II) complex supported by two β-enaminoketiminato ligands, bis[(cyclohexylamino)pent-2-en-4-onato]-chromium(II), has been synthesized and has been structurally characterized in two different crystal phases.      

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 Structural Characterization of Bis(μ2-Iodo)-Bis(Diethyl Ether)-(N-N′-(Bis(2,6-Diisopropylphenyl)Pentane-2,4-Diketiminato)-Lithium-Chromium, a Cr(II) (β-Diketiminato) Complex with a Coordinated LiI Salt

Abstract  Addition of CrI₂ to the lithium salt of N-N′-bis(2,6-diisopropylphenyl)-2,4-diketiminate in diethylether yields a Cr(II) iodide complex with a coordinated, solvated LiI salt. This complex is the intermediate in the synthesis of a bridging iodide complex that is itself a precursor to a side-on bridging dinitrogen complex. This complex crystallizes in the P2₁/n space group with the crystal cell parameters a = 12.3160(19) ?, b = 21.067(3) ?, c = 15.837(3)?, β = 96.767°, V = 4080.6(11) ?³ and Z = 4. Graphical Abstract  Addition CrI2 to the lithium salt of N-N′-bis(2,6- diisopropylphenyl)-2,4-diketiminate in diethylether yields a Cr(II) iodide complex with a coordinated, solvated LiI salt. Herein we report the spectroscopic and structural characterization. An erratum to this article can be found at     

Synthesis, Crystal Structures and Properties of Two Copper (II) Complexes with Pyridazine Derivative Ligand

Abstract  Two new complexes, [Cu(L)₂(CH₃OH)] · (ClO₄)₂ (1) and [Cu(L)₂(H₂O)] · (NO₃)₂ (2), have been synthesized and their crystal structures have been determined by X-ray analysis, where L = 3-(3,5-bimethylpyrazole-yl)-6-chloro-pyridazine]. The complex 1 crystallizes in the monoclinic, space group C2/c, and the coordination configuration of copper (II) is better described as trigonal pyramidal geometry with four N atoms from L and one O_methanol^. The coordination configuration of 2 is quite similar to that of 1 except O_water instead of O_methanol^. The intermolecular hydrogen bonds link the repeat units and extend the molecules to multinuclear structures in both compounds. The spectral properties of the title compounds have been studied and discussed. Furthermore, the antibacterial activities of the title compounds have been detected, the results indicate that the ligands and two copper(II) complexes exhibit certain fungicidal activities again several bacteria. Index Abstract  Two new complexes, [Cu(L)2(CH3OH)]·(ClO4)2 (1) and [Cu(L)2(H2O)]·(NO3)2 (2), have been synthesized and their crystal structures have been determined by X-ray analysis, where L= 3-(3,5-bimethylpyrazole-yl)-6-chloro-pyridazine. The intermolecular hydrogen bonds extend the molecules to multinuclear structures in both compounds.      

Dichloro-{bis(Pyrazol-1-yl)}Palladium(II) Complexes: Structures of a DMSO Solvated Dichloro-{bis(3,5-Dimethylpyrazol-1-yl)Acetic Acid}Palladium(II) and Dichloro-{bis(3,5-Ditertbutylpyrazol-1-yl)Methane}Palladium(II)

Abstract  Two new palladium(II) complexes, dichloro-{bis(3,5-dimethylpyrazol-1-yl)acetic acid}palladium(II)PdCl₂(3,5-Me₂bpza)], (1) (3,5-Me₂bpza = 3,5-dimethylpyrazol-1-yl)acetic acid) and dichloro-{bis(3,5-ditertbutylpyrazol-1-yl)acetic acid}palladium(II), [PdCl₂(3,5-^tBu₂bpza)], (2a) [3,5- ^t Bu₂bpza = 3,5-ditertiarybutylpyrazol-1-yl)acetic acid] complexes, were synthesized from the reactions of pyrazol-1-yl ligands with palladium salts. Attempts to crystallize 2a led to a hydrolyzed product, dichloro-{3,5-ditertbutylpyrazol-1-yl}palladium(II) (2b), in which the acetic acid moiety in the ligand backbone of 1 is lost. Both complexes 1 and 2b have been characterized by single-crystal X-ray crystallography. Both complexes crystallized in triclinic system (P − 1 space group). The cell parameters are: complex 1 (a = 8.7960(14) Å, b = 16.238(2) Å, c = 16.430(2) Å, α = 78.038(10)°, β = 77.817(11)°, γ = 89.970(10)°) and complex 2b (a = 10.1492(2) Å, b = 12.4001(2) Å, c = 13.108(3) Å, α = 103.0690(10)°, β = 97.4120(10)°, γ = 107.2450(10)°). The asymmetric unit of 1 contains two crystallographic independent monomeric units of 1 and three molecules of DMSO solvent, whilst that of 2b has got one monomeric unit with one molecule of chloroform solvent. Index Abstract  Two palladium complexes, dichloro-{bis(3,5-dimethylpyrazol-1-yl)acetic acid}palladium(II), PdCl₂(3,5-Me₂bpza)], (1) (3,5-Me₂bpza = 3,5-dimethylpyrazol-1-yl)acetic acid) and dichloro-{bis(3,5-ditertbutylpyrazol-1-yl)acetic acid}palladium(II), [PdCl₂(3,5- ^t Bu₂bpza)], (3,5- ^t Bu₂bpza = 3,5-ditertiarybutylpyrazol-1-yl)acetic acid) complexes, were synthesized from the reactions of pyrazol-1-yl ligands with palladium salts. Attempt to obtain crystals of tertiarybutylpyrazolyl analogue led to hydrolysis, the crystal structure of the hydrolysis product was established by single crystal X-ray crystallography.      

Crystal structures of the cobalt(III), nickel(II), copper(II), and zinc(II) complexes of 2-thio-6-picoline N-oxide

Structures of the following compounds have been solved: tris(2-thio-6-picoline N-oxide)cobalt(III), [Co(6MOS)₃], orthorhombic, Pca2₁, a = 17.871(3), b = 14.061(2), c = 15.964(2) Å, V = 4011(1) ų, Z = 8, and = 1.193 mm^–1; bis (2-thio-6-picoline N-oxide)nickel(II), [Ni(6MOS)₂], orthorhombic, Pbca, a = 15.602(8), b = 13.606(4), c = 13.348(8) Å, V = 2833(4) ų, Z = 8, and = 1.655 mm^–1; bis(2-thio-6-picoline N-oxide)copper(II), [Cu(6MOS)₂], orthorhombic, Pbca, a = 13.914(5), b = 12.984(5), c = 15.663(6) Å, V = 2830(2) ų, Z = 8, and = 1.836 mm^–1; and bis(2-thio-6-picoline N-oxide)zinc(II), [Zn(6MOS)₂], triclinic, P – 1, a = 7.9737(8), b = 11.7786(9), c = 7.9206(8) Å, = 104.502(7), = 104.495(8), = 93.445(8)°, V = 691.3(1) ų, Z = 2, and = 2.106 mm^–1. The steric effect of the methyl group in the six-position of the N-oxide ring is considered in comparing these structures to complexes of 2-thiopyridine N-oxide.     

Synthesis and crystal structure of bis(4-methylpiperidine-dithiocarbamato-S,S′)-palladium(II)

The complex bis(4-methylpiperidine-dithiocarbamato-S,S′)-palladium(II) was synthesized by the reaction of 4-methyl-1-piperidine dithiocarbamic acid with palladium(II) chloride. Its structure was determined by X-ray crystal diffraction analysis. It crystallizes in the monoclinic P2₁/c space group with the crystal cell parameters a=8.6491(8) ?, b=18.7305(16) ?, c=11.9933(10) ?, β=107.074(1)°, V=1857.3(3) ?³ and Z=4. The palladium (II) ion is bonded to four sulfur atoms, belonging to two dithiocarbamate ligands, in a distorted square planar geometry. The X-ray data suggest a pronounced electronic delocalization in the two NCS₂ moieties.     

Synthesis and crystal structure of macrocyclic nickel(II) complex bridged by chromate

A novel compound catena-(-CrO₄-O,O)[Ni(L¹)Ni(L²)] 3H₂O (1) (L¹ = 3,5,10,12-tetramethyl-1,4,8,11-tetraazacyclotetradecane and L² = 2,5,9,12-tetramethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized for the first time and structurally characterized. 1 crystallizes in the triclinic space group P with a = 9.623(1), b = 10.084(1), c = 12.723 (3) Å, = 66.74(2), = 75.20(1), = 72.02(1)°, V = 1066.2(3) ų, and Z = 2. The coordination environment around the Ni(II) ions is an axially elongated octahedron with the secondary amines of the isomeric ligands and two oxygen atoms of [CrO₄]^2–.     

Synthesis,Characterization and Crystal Structure Determination of a Hepta-coordinated Cadmium(II) Complex with Thiocyanato-bridges

Abstract  A new cadmium(II) complex [(C₂₈H₂₄N₆)Cd(SCN)₂]₂(CH₃OH)₂ (1) has been synthesized and characterized by IR, UV spectra, TG-DTA technique and single crystal X-ray diffraction analysis. The crystallographic data for compound 1: triclinic P1ˉ, a = 9.630(2) Å, b = 11.123(3) Å, c = 15.396(4) Å, α = 106.93(1)°, β = 91.60(1)°, γ = 99.99(1)°, V = 1,548.5(6) Å³, Z = 1, Dc = 1.512 mg/m³, F(000) = 716, R ₁ = 0.0332, wR ₂ = 0.0907. The molecule contains a symmetrical dinuclear unit in which two Cd(II) ions are double bridged by two di-μ-1,3-SCN⁻ anoins with a cadmium–cadmium separation of 6.48 Å. Each Cd(II) ion is seven-coordinated with six nitrogen atoms and a sulfur atom to form a monocapped trigonal prism coordination geometry. In addition, the molecule is further connected by multiform intermolecular C–H···π, π···π interactions and hydrogen bonds to form a three-dimensional supramolecular structure. Graphical Abstract  A hepta-coordinated Cd(II) complex which exhibits a distorted a monocapped trigonal prism coordination geometry has been achieved by using bisbidentate Schiff-base ligand and thiocyanate anion.      

Distortion Isomerism of Cu(II) Chloride Adducts with Bis(2-benzimidazolyl)ethane. Synthesis,Characterization, X-ray Structures and Spectroscopy of Four Different Isomers

3D structures and spectroscopic properties are reported of four compounds with the ligand bis(2-benzimidazolyl)ethane (hereafter abbreviated as dbz) attached to CuCl₂, all having the general formula [Cu(dbz)Cl₂](Hb) _x . (in which Hb = EtOH or MeOH and x = 1/2 or 1). The X-ray crystal structure has been solved from these four slightly different compounds, namely: green α-[CuCl₂dbz](C₂H₅OH)_1/2 (1), the red compound β-[CuCl₂dbz](C₂H₅OH)_1/2 (2), which both have two slightly different units in the unit cell, the red α-[CuCl₂dbz](CH₃OH) (3) and a blue–green compound β-[CuCl₂dbz](CH₃OH) (4). The geometry around the Cu(II) anion is distorted tetrahedral for all four compounds, with chromophores consisting of two nitrogen atoms of the bidentate chelating dbz molecule and two chloride anions. The unit cells of compound 1 and 2 consist of two chemically identical, but crystallographically different units, while compounds 3 and 4 each have only one independent CuCl₂-(dbz) unit. The major differences are observed in the dihedral angles NCuN–ClCuCl, which vary from 29.3 to 77.1° for the four compounds. The differences are related to different packing effects, ring–ring stacking and H-bond interaction, due to the two different alcohols used. In fact these four compounds represent a new range of examples of distortion isomerism in pseudo-tetrahedrally coordinated species. Characterisation of the four compounds has been completed by IR, EPR and LF spectroscopy.     

Crystal structure of bis[dihydrobis(3,5-dimethy-1-pyrazolyl)borato]cadmium(II)

The structure of [H₂B(3,5-Me₂pz)₂]₂Cd shows the four nitrogen donor atoms form a pseudotetrahedral arrangement about the cadmium(II). The intraligand N—Cd—N angles are restricted to an average of 91.4° by the chelate rings forcing the interligand N—Cd—N bond angles to average 119.4°. The Cd—N bond distances average 2.21 Å with a range of 0.04 Å. The crystal is in the triclinic space group, P with a = 7.6793(2) Å, b = 8.5992(2) Å, c = 25.0874(4) Å, = 91.0791(2)°, = 97.9769(4)°, = 110.2344(6)°, and Z = 2.     

Synthesis and Crystal Structure of a Cyano-Bridged Bimetallic Nickel(II)–Silver(I) Complex, [Ni(dmen)<Subscript>2</Subscript>{Ag(CN)<Subscript>2</Subscript>}<Subscript>2</Subscript>] · 0.5H<Subscript>2</Subscript>O

A cyano-bridged heteronuclear bimetallic complex [Ni(dmen)₂{Ag(CN)₂}₂] · 0.5H₂O (dmen = N,N′-dimethylethylenediamine) has been prepared and characterized by IR spectroscopy and X-ray Crystallography. The compound crystallizes in the monoclinic space group P2₁/c. The crystal structure of the complex consists of two independent centrosymmetric trinuclear molecules made up of a [Ni(dmen)₂] ⁺² unit linked to two [Ag(CN)₂]⁻ anions in a trans configuration. The trinuclear units are joined by hydrogen bonding to form irregular chains.     

Synthesis,Properties, and Crystal Structures of Copper(II) Di-(2-picolyl)amine Complexes Containing Inorganic Salts

Abstract These complexes have been characterized by X-ray crystallography, spectroscopic, and cyclic voltammetry. In 1, the copper(II) ion has a distorted square-pyramidal geometry with three nitrogen atoms of the dpa ligand and two oxygen atoms of the nitrate anions. The crystal structure of 2 shows that the copper(II) ions are bridged by tp anion to form a dinuclear complex, in which each copper(II) ion exhibits a distorted square-pyramid with three nitrogen atoms of the dpa ligand, water molecule, and the oxygen atom of the bridging tp ligand. Cyclic voltammetric data indicate that 1 undergoes irreversible one-electron oxidation to the Cu^III and reversible one-electron reduction to the Cu^I, while 2 gives one reversible oxidation and two reversible and irreversible reduced processes. The electronic spectra and redox potentials of the complexes are influenced significantly by the anionic ligands. Graphical Abstract The reaction of [Cu(dpa)Cl₂] with K(NO₃)₂ and Na₂tp yields mononuclear and dinuclear copper(II) complexes [Cu(dpa)(NO₃)₂] (1) and [Cu₂(dpa)₂(H₂O)₂(μ-tp)](tp)·6H₂O (2) (dpa = di-(2-picolyl)amine, tp = terephthalate).      

Crystal structure of a macrocyclic tetraamine isocyanato zinc(II) complex

The complex, [Zn(L)(NCO)]Cl · 3H₂O (1) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0^1.18,0^7.12]docosane), has been synthesized and structurally characterized. 1 crystallizes in the monoclinic system, space group P2₁/n with a = 10.530(3), b = 9.315(2), c = 27.188(3) Å, = 92.58(1)°, V = 2664.1(9)ų, and Z = 4. The zinc atom is in a distorted squarepyramidal environment with the four nitrogen atoms of the macrocycle and one nitrogen atom of the isocyanate ligand.     

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.     

Synthesis and Crystal Structure of the Hydrated Nickel(II) Complex of Tartrate

Abstract  A new dinuclear hydrated nickel(II) tartrate has been isolated and structurally characterized by single-crystal X-ray diffraction. The title compound formulated as [Ni₄(C₄H₄O₆)₄(H₂O)₈](EtOH)_0.5(H₂O)_10.25 (C₁₇H_55.5Ni₄O_42.75) crystallizes in monoclinic system, space group P2(1)/c with a = 13.684(5), b = 17.143(6), c = 18.586(6) ?, β = 96.638(6)°, V = 4331(3) ?³, Z = 4. The unit cell contains two crystallographic independent dimeric units of [Ni₂(C₄H₄O₆)₂(H₂O)₄] without significant structural difference, half of menthol molecule and ten and a quarter packing water molecules. In each dimeric unit, one (R,R)-tartrato dianion chelates two Ni(II) ions by the use of two hydroxy oxygen and two carboxyl oxygen atoms as donor atoms, and another tartrato dianion chelates the same pair of Ni(II) cations in the same way. Each Ni(II) atom is six-coordinated by six O atoms from two tartrate units and two water molecules. Index Abstract  The crystal structure of complex [Ni₄(C₄H₄O₆)₄(H₂O)₈](EtOH)_0.5(H₂O)_10.25 contains two crystallographic independent dimeric units of [Ni₂(C₄H₄O₆)₂(H₂O)₄] without significant structural difference. In each dimeric unit, one (R,R)-tartrato dianion chelates two Ni(II) ions by the use of two hydroxy oxygen and two carboxyl oxygen atoms as donor atoms, and another tartrato dianion chelates the same pair of Ni(II) cations in the same way.      

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.     

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.