Synthesis,crystal structure,and magnetism of [Mn(hfac)2NIT(Ph-m-OPh)]

A new complex [Mn(hfac)₂NIT(Ph-m-OPh)] has been synthesized and structurally characterized by X-ray diffraction. It crystallizes in the monoclinic space group P2(1)/c. The structure consists of a 1-D chain with Mn(II) bridged by NIT(Ph-m-OPh). The manganese(II) is in a distorted octahedral environment formed by one oxygen from NIT(Ph-m-OPh) and three atoms from hexafluoro acetylacetone (hfac) in the equatorial plane and two oxygens from hfac and the other NIT(Ph-m-OPh) in the axial position. The units of [Mn(hfac)₂NIT(Ph-m-OPh)] are connected as a 1-D chain by Mn(II) and oxygen of N–O in bridging NIT(Ph-m-OPh) along the b-axis. The 2-D layer in the ab plane is formed via hydrogen interactions to connect neighboring chains. The complex exhibits intramolecular antiferromagnetic interactions between Mn(II) and NIT(Ph-m-OPh).     

Synthesis and crystal structure of a new lapacholate complex with nickel(II), [Ni(Lap)2(DMF)(H2O)]

The crystal and molecular structure of dilapacholateaqua(dimethylformamide)nickel(II) was determined by X-ray diffraction. It crystallizes in the triclinic space group P 1 with a = 9.8671(9) Å, b = 10.654(1) Å, c = 15.289(2) Å, α = 86.98(1)°, β = 79.32(1)°, γ = 87.031(8)°, and Z = two molecules per unit cell. The structure was solved from 5094 reflections with I>2σ(I) and refined by full matrix least-square to an agreement R ₁-factor of 0.0564. The nickel(II) is in a NiO₆ octahedral environment, cis coordinated to two lapacholate anions through their adjacent carbonyl [Ni–O distances of 2.075(2) and 2.066(2) Å], and phenyl oxygens [Ni–O lengths of 2.011(2) and 2.021(2) Å], and to a water [d(Ni–Ow) = 2.073(2) Å] and a DMF [d(Ni–O) = 2.076(2) Å] at axial positions. Some physicochemical and spectroscopic properties of the complex are also reported.     

Crystal and molecular structure of pyridazine-3-carboxylic acid hydrochloride and zinc(II) pyridazine-3-carboxylate tetrahydrate

Crystals of pyridazine-3-carboxylic acid hydrochloride contain almost planar molecular sheets in which the cations, composed of acid molecules each with a hydrogen atom attached to one of the ring-nitrogen atoms, interact with chloride anions via a network of weak hydrogen bonds. Van der Waals interactions between sheets are indicated by the intersheet spacing of 3.47?Å. The crystal structure of di(aqua-O)bis(trans-pyridazine-3-carboxylato-N,O)zinc(II) dihydrate is composed of monomeric molecules in which the zinc(II) ion at the center of symmetry is coordinated by two ligand molecules each via its N,O bonding moiety. The ligand molecules and the metal ion form a trans-planar configuration. Two water oxygen atoms, above and below the plane, complete a distorted octahedron. A network of weak hydrogen bonds holds the monomers together.     

Synthese und Kristallstrukturen der Samarium-Komplexe [SmI2(DME)3] und [Sm2I(NPPh3)5(DME)]

Synthesis and Crystal Structures of the Samarium Complexes [SmI₂(DME)₃] and [Sm₂I(NPPh₃)₅(DME)] When treated with ultrasound, the reaction of samarium metal with N-iodine-triphenylphosphaneimine in 1,2-dimethoxyethane (DME) leads to the two samarium complexes [SmI₂(DME)₃] ( 1 ) and [Sm₂I(NPPh₃)₅(DME)] ( 2 ), which are separated from each other by fractional crystallization. 1 could be isolated in two different crystallographic forms, namely as brownish black crystals ( 1 a ) and as violet-black crystals ( 1 b ), both of them are characterized by crystal structure analyses. 1 a : Space group P2₁/c, Z = 4, lattice dimensions at –80 °C: a = 1459.4(1), b = 1314.4(1), c = 2293.6(2) pm, β = 99.245(8)°, R = 0.0344. The structure of 1 a holds two crystallographically independent molecules [SmI₂(DME)₃], in which the samarium atoms have coordination number eight. The two individuals differ from each other particularly in their I–Sm–I bond angles, which are 157.94 and 178.45°. 1 b : Space group P2₁, Z = 2, lattice dimensions at –80 °C: a = 849.4(3), b = 1060.1(3), c = 1235.1(6) pm, b = 93.86(5)°, R = 0.0251. 1 b has a molecular structure similar to that of 1a with a bond angle I–Sm–I of 158.40°. The phosphoraneiminato complex [Sm₂I(NPPh₃)₅(DME)] ( 2 ) forms colourless, moisture sensitive crystals which contain two molecules DME per formula unit. 2 · 2 DME: Space group P1, Z = 2, lattice dimensions at –80 °C: a = 1405.0(4), b = 1656.5(3), c = 2208.3(7) pm, α = 89.60(3)°, β = 72.96(4)°, γ = 78.70(3)°, R = 0.0408. In 2 the two samarium atoms are linked via the μ-N atoms of two phosphoraneiminato ligands to form a planar Sm₂N₂ four-membered ring. One of the Sm atoms is terminally coordinated by the N atoms of two (NPPh₃)^– groups, thus achieving a distorted tetrahedral surrounding. The second Sm atom is coordinated by the N atom of one (NPPh₃)^– group, by the terminally bonded iodine atom, and by the O atoms of the DME chelate, thus achieving a distorted octahedral surrounding.     

Synthesis,crystal structure and fluorescence of a two-dimensional Cd(II) coordination polymer with thiocyanato and 4-methylpyridine N -oxide as bridging ligands

A two-dimensional coordination complex [Cd(μ_1,3-SCN)₂(μ₂-mpdo)] _n (mpdo?=?4-methylpyridine N-oxide) has been synthesized and structurally determined by X-ray crystallography. The complex crystallizes in the triclinic space group of Pī with a?=?8.2589(14)?Å, b?=?8.5409(14)?Å, c?=?9.7947(16)?Å, α?=?70.022(2)°, β?=?74.338(2)°, γ?=?71.530(2)°. Each Cd(II) is coordinated by four μ_1,3-SCN^? forming a zigzag chain and then two μ₂-mpdo monodentate ligands coordinate to two adjacent Cd(II) ions leading to a two-dimensional sheet structure along the ab plane, and in the c direction the sheets stack parallel through π–π interactions and giving a three-dimensional structure. The complex exhibits a strong fluorescent emission spectrum in the solid state.     

A New Type of Anionic Framework in Microporous Potassium Iron(II) Phosphate K[Fe(PO4)]

A new iron(II) orthophosphate K[Fe(PO₄)] has been obtained by hydrothermal synthesis and its crystal structure was determined by single‐crystal X‐ray diffraction: space group P2₁/n, Z = 8, a = 9.6199(10), b = 8.6756(8), c = 10.8996(13) Å, β = 115.577(8)° at 193 K, R = 0.023. Fe^II shows coordination numbers (CN) 4 (distorted tetrahedral) and CN 5 (distorted trigonal bipyramidal). The [FeO₄] and [FeO₅] units form together with the [PO₄] tetrahedra a microporous 3D para‐framework with open channels along the a and b directions. The potassium ions positioned in the channels show CN 7 and 8. The structural relations within the morphotropic row of non‐isotypic K[M(PO₄)] structures (M = Zn, Ni, Mn, Fe) are discussed on the basis of common basic structural units.     

Synthesis,crystal structure,spectroscopy and magnetism of a trinuclear nickel(II) complex with 3,5-pyrazoledicarboxylic acid as bridge ligands

A new complex of [Ni₃(dcp)₂(H₂O)₁₀] (1) (H₃dcp = 3,5-pyrazoledicarboxylic acid) has been synthesized from H₃dcp and Ni(NO₃)₂·6H₂O by hydrothermal reaction. Complex 1 has the discrete trinuclear structure. Three Ni(II) ions are bridged by two dcp³⁻ ligands, with 10 coordinated water molecules as terminal ligands. The molecules of [Ni₃(dcp)₂(H₂O)₁₀] extend into three-dimensional supramolecular architectures by intermolecular O–H···O hydrogen bonds as well as π-π stacking interactions. Magnetic susceptibility measurement shows that a weak antiferromagnetic interaction is operative between nickel(II) ions and an excellent simulation of the experimental data gives D = 5.27 cm⁻¹, J = −2.19 cm⁻¹ and g = 2.05.     

Copper(II) complexes of tridentate SNO ligands: synthesis,characterization and crystal structure

A new series of binary copper(II) complexes, [Cu(L)₂] (2) [where L is a monobasic tridentate methylthioazophenolate having NSO donor sets], has been synthesized. The reddish brown colored complexes have been characterized by elemental analyses, spectroscopic and other physico-chemical tools. The detailed structure analysis of one of the complexes, [Cu(1a)₂] (2a), by single-crystal X-ray crystallography shows that thioether-S donor center participates in coordination with the copper(II) ion with a weak interaction with long Cu–S(thioether) bond distances [2.956(2) Å and 2.925(2) Å]. Electrochemical study of the complexes in methanol using TBAP as supporting electrolyte shows that heterogeneous electron-transfer rate is low at the applied potential.     

Chloro-bridged complexes of copper(II) and manganese(II) derived from unsymmetric bidentate ligands: synthesis,crystal structure and characterization

Two new usymmetric bidentate Schiff-base ligands (2-pyridyl-2-furylmethyl)imine (L1) and (2-pyridyl-phenylmethyl)imine (L2) were prepared. The crystal structures of two chloro-bridged complexes [Cu₂(μ-Cl)₂(L1)₂Cl₂] (1) and [Mn (μ-Cl)₂(L2)] (2) derived from the each ligand have been confirmed by single-crystal X-ray diffraction analysis. The complexes were characterized by IR, elemental analysis and spectroscopic methods. In complex 1, the two copper atoms are five-coordinate involving a square-pyramidal geometry having a N₂Cl₃ donor set with the two chlorine atoms bridging the two copper atoms. In complex 2, the manganese atoms are both six-coordinate. In contrast to 1, all chlorine atoms in 2 are bridging chlorides and link adjacent manganese atoms together forming 1-D infinite chains.     

Synthesis and crystal structure of nitrosoruthenium aquadiammine complex, [Ru(NO)(NH3)2Cl2(H2O)]Cl·H2O

The reaction between [RuNO(NH₃)₂(NO₂)₂OH] and an excess of 3 M HCl leads to denitration of the starting complex and precipitation of [Ru(NO)(NH₃)₂Cl₃]. Crystals of the tittle complex have been obtained by evaporation of the mother liquor at ambient temperature. The crystal structure of the product has been determined. The linear nitroso group and a water molecule are coordinated in the trans positions, three nitrogen atoms from NO and NH₃ ligands occupy the coordination octahedron face.     

Copper(II) complexes of N4 tetradentate ligands with flexible alkyl spacers: Crystal structure,DNA binding and cleavage studies

Mononuclear copper(II) complexes, [Cu L1] (ClO₄)₂ (1), [Cu L2] (ClO₄)₂ (2) and [Cu L3] (ClO₄)₂ (3) with quadridentate Schiff base ligands L1 (N,N′-bis-pyridin-2-ylmethyl-butane-1,4-diimine), L2 (N,N′-bis-pyridin-2-ylmethyl-pentane-1,5-diimine) and L3 (N,N′-bis-pyridin-2-ylmethyl-hexane-1,6-diimine) have been synthesized and characterized. The crystal structure data of 1 reveals the existence of the complex in two different geometries, namely a square pyramid and a distorted octahedron, which eventually leads to the packing of the molecule into helical and anti-parallel structures respectively. Absorption titration studies with calf thymus DNA for all three complexes are suggestive of groove binding with binding constant values for 1, 2 and 3 being 2.6 ± 0.2 × 10⁴ M⁻¹, 11.5 ± 0.2 × 10⁴ M⁻¹ and 1.83 ± 0.2 × 10⁴ M⁻¹ respectively. Control cleavage experiments using pBR 322 plasmid DNA and distamycin suggest minor groove binding for these complexes. In the presence of ascorbic acid, the complexes show efficient DNA cleavage, the order of efficiency being 1 > 2 ≅ 3.     

Nickel(II) complexes of tetradentate NSNO pyridylthioazophenol ligands: Synthesis,characterization and crystal structure

Two sets of nickel(II) complexes of a series of tetradentate NSNO ligands were synthesized and isolated in their pure form. All these complexes, formulated as [Ni(L)Cl]₂ and [Ni(L)(N₃)]₂ [HL = pyridylthioazophenols], were characterized using physicochemical and spectroscopic tools. The solid-state structures of two complexes (1a and 2a) were established by X-ray crystallography. The geometry about the nickel ion of the complexes is octahedral and the complexes are dimeric in nature. In 1, two Ni(II) ions are bridged by two Cl⁻ anions while in 2 they are bridged by two azide ions in a μ-1,1-bridging fashion.     

Kaliumtriamidostannat(II), K[Sn(NH2)3] – Synthese und Kristallstruktur

Potassium Triamidostannate(II), K[Sn(NH₂)₃] – Synthesis and Crystal Structure Rusty‐red crystals of K[Sn(NH₂)₃] were obtained by the reaction of SnBr₂ and KNH₂ in a 1 : 3 molar ratio in liquid ammonia at 233 K in the form of platelets. The structure was determined from single crystal X‐ray diffractometer data: Space group P3; Z = 2; a = 6.560(1) Å, c = 7.413(2) Å. The structure contains trigonal pyramidal complex anions [Sn(NH₂)₃]^– and potassium cations. These ions are arranged to one another following the motif of a strongly distorted hexagonal close packing of sequence A(Sn) B(Sn) A′(K) B′(K) …     

Crystal structure,thermal and magnetic studies of a dinuclear Mn(II) complex with decadentate picolinate based ligand

The reaction of the decadentate ligand tpmen (H₄tpmen?=?N,N,N′N′-tetrakis[(6-carboxypyridin-2-yl)methyl]ethylenediamine) with MnCl₂·4H₂O in aqueous solution gives a homodinuclear complex [Mn₂(H₂O)₂(tpmen)]·16H₂O, which has been characterized by elemental analysis, thermal gravimetric and single-crystal X-ray diffraction analysis. The complex crystallizes in the orthorhombic system, space group Cmca, a?=?28.786(5) Å, b?=?11.5033(19) Å, c?=?14.437(2) Å, Z?=?8, R ₁?=?0.0432, wR ₂?=?0.0786. The tpmen ligand contains four picolinate groups, two of which bind each Mn(II) to form a dinuclear complex. The geometry around the Mn(II) is distorted octahedral with two nitrogen and two oxygen atoms from the picolinate groups and two oxygen atoms from coordinated water. The variable-temperature (2–300?K) magnetic susceptibilities shows an antiferromagnetic interaction between Mn(II) ions.     

Crystal structure and fluorescence spectrum of the complex [Eu(III)(TTA)3(phen)]

The title complex Eu(III)(TTA)₃(phen) (where TTA = thenoyltrifluoroacetone monoanion; phen = 1,10-phenanthroline) has been synthesized in mixed solvents of acetone and ethanol (1:1 volume ratio) and its crystal structure has been determined by X-ray diffraction. The complex crystals are triclinic, space group P 1 (# 2) with cell dimensions of a = 1.32.41 (2) nm, b = 1.5278(4) nm, c = 0.9755(3) nm, α = 92.49 (2)°, β = 102.57(2)°, γ = 91.62(2)°, V = 1.9268(8) nm³, Z = 2, μ (Mo Ka)= 18.77 cm^?1, D_x=1.720 g/cm³. The coordination geometry of Eu atom is a distorted square antiprism, and the encapsulated structure that can meet the structural requirement of the typical europium luminescent sensor. The fluorescence spectrum suggests that the complex is a strong photoluminescent material.     

Synthesis,Characterization and Crystal Structures of Four Dinuclear Schiff Base Nickel(II) and Copper(II) Complexes with Versatile Bridging Groups

Four novel Schiff base nickel(II) and copper(II) complexes, derived from the end‐on (μ_1,1‐N₃) azide, end‐to‐end (μ_1,3‐NCS) thiocyanate, or phenolate oxygen bridges, have been synthesized and their crystal structures determined by X‐ray diffraction methods. They are the dinuclear double end‐on azide‐bridged [Ni₂(L1)₂(MeCN)₂(μ_1,1‐N₃)₂]·MeOH ( 1 ), the dinuclear double end‐on azide‐bridged [Ni₂(L2)₂(MeOH)₂(μ_1,1‐N₃)₂][Ni₂(L2)₂(OH₂)₂(μ_1,1‐N₃)₂]·MeOH ( 2 ), the dinuclear double end‐to‐end thiocyanate‐bridged [Cu₂(L3)₂(μ_1,3‐NCS)₂] ( 3 ), and the dinuclear double phenolate O‐bridged [Cu₂(L4)₂(NCS)₂] ( 4 ), where HL1, HL2, HL3 and HL4 are four tridentate Schiff bases obtained by the condensation of 3,5‐dibromosalicylaldehyde with N‐ethylethane‐1,2‐diamine, of 3,5‐dichlorosalicylaldehyde with N‐methylpropane‐1,3‐diamine, of 3‐bromo‐5‐chlorosalicylaldehyde with 2‐aminomethylpyridine, and of 5‐nitrosalicylaldehyde with 2‐aminomethylpyridine, respectively. Each nickel(II) atom in 1 and 2 is in an octahedral coordination, while each copper(II) atom in 3 and 4 is in a square pyramidal coordination. There exists crystallographic inversion centre symmetry in each of the complexes.     

Synthesis,crystal structures and fluorescence of cadmium(II) coordination polymers with derivatives of pyrazine-1,4-dioxide and thiocyanate as mixed-bridging ligands

Two Cd(II) coordination polymers have been synthesized with derivatives of pyrazine-1,4-dioxide and thiocyanate anion as bridging ligands and structurally determined by X-ray crystallography. Complex 1, [Cd(μ_1,3-SCN^?)₂(μ_1,6-L1)] _n (L1?=?2,5-dimethylpyrazine-1,4-dioxide), belongs to the triclinic, space group P 1 with a?=?5.7627(18)?Å, b?=?7.182(2)?Å, c?=?7.509(2)?Å, α?=?74.042(3)°, β?=?84.766(4)°, γ?=?88.162(4)°; complex 2, [Cd₂(μ_1,3-SCN^?)₄(μ₄-L2)] _n (L2?=?2,3,5,6-tetramethylpyrazine-1,4-dioxide), crystallizes in a monoclinic system with space group C2/m with a?=?10.194(4)?Å, b?=?13.491(6)?Å, c?=?8.140(3)?Å, β?=?120.372(4)°. Complex 1 shows a two-dimensional sheet structure, and in a direction the Cd(II) ions were coordinated by μ_1,3-SCN^? forming the one-dimensional chain and the L1 bridging ligand made the chains connect in the c direction leading to formation of a two-dimensional sheet on the ac plane. For 2 the one-dimensional chains in the a axis were constructed by coordination of μ_1,3-SCN^? bridging ligands with the Cd(II) ions, and in b and c directions the chains were joined by L2 bridging ligands leading to a three-dimensional structure. In 2 L2 displays a μ₄-bridging coordination mode. Both complexes exhibit strong fluorescence emission.     

Synthesis,crystal structure,and magnetic properties of a new Fe(II) complex with reduced radical ligands

A new Fe(II) complex, [Fe(HIM2Py)₂(N(CN)₂)₂]?·?2H₂O (HIM2py?=?1-hydroxyl-2(2′-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1?H-imidazole), has been synthesized and characterized. The X-ray analysis reveals that HIM2py ligands are coordinated to iron as an unusual six-membered bidentate chelate with κ²N(py), O(HIM) mode. The variable-temperature magnetic susceptibility suggests that weak antiferromagnetic interactions exist in the complex.     

Synthesis,structure and properties of three one-dimensional coordination polymers {[M(II)L(NCS)2](DMF)2} n (M(II)=cadmium(II), zinc(II), manganese(II); L=1,4-bis[2-(2-pyridyl)benzimidazolato]butane)

A tetradentate N-donor ligand 1,4-bis[2-(2-pyridyl)benzimidazolato]butane (L) was prepared for construction of a coordination framework. Three one-dimensional coordination polymers {[M(II)L(NCS)₂](DMF)₂} _n (M(II) = cadmium(II), 1, zinc(II), 2, manganese(II), 3) were obtained by reaction of metal ions and L in the presence of KSCN in DMF/water. The complexes are isostructural and consist of 1D zigzag [M(II)L(NCS)₂] _n chains and DMF molecules. Within the chains, the metal atoms are each octahedrally coordinated by four N atoms of L and two N atoms of the SCN^? anions. Complexes 1 and 2 in the solid state at room temperature exhibit intense photoluminescence at 453 and 433 nm, respectively.     

Hydrothermal synthesis and crystal structure of a layered coordination polymer: [Zn2(C2O4)2(C3N2H4)2] n

A new metal-organic coordination polymer [Zn₂(C₂O₄)₂(C₃N₂H₄)₂] _n (1) has been hydrothermally synthesized with ZnCl₂·2H₂O, oxalic acid and imidazole. The compound has a 2D network, consisting of infinite zinc(II) oxalate chains connected to each other by three-coordinate oxygen atoms. Within the chains, the zinc atoms are each octahedrally coordinated by one nitrogen atom from imidazole and five oxygen atoms from oxalate groups. Furthermore, there are two coordination modes of oxalate to zinc ions: chelate bis-bidentate and chelate/bridging bis-bidentate in compound 1, and the latter is rare among related compounds. Crystal data: monoclinic, P2(1)/c, a?=?8.4310(17), b?=?9.4060(19), c?=?8.2790(17)?Å, β?=?93.15(3)°, V?=?655.5(2)?ų, Z?=?2, R ₁?=?0.0322, wR ₂?=?0.0850.