Penta- and hexacoordinate antimony(V) compounds with the tridentate O,N,O-donor ligand: Electrochemical transformations and antiradical activity

The electrochemical transformations and antiradical activity of penta- and hexacoordinate antimony(V) complexes I–V containing the tridentate O,N,O-donor ligand, N,N-bis(di-3,5-tert-butyl-2-hydroxyphenyl)amine, are studied. The oxidation of hexacoordinate triarylantimony(V) compounds R₃Sb(Cat-NH-Cat) (I–III) leads to the formation of neutral paramagnetic intermediates Ia–IIIa. Two anodic reversible one-electron stages are observed for pentacoordinate complexes R′₂Sb(Cat-N-Cat) (IV, V). The possibility of the formation of stable paramagnetic species in electrochemical oxidation is a reason for the antiradical activity of the complexes. The study of the reactions of compounds I–V with the electrogenerated superoxide radical anion, diphenylpicrylhydrazyl radical, peroxy radicals, and hydroperoxides formed by the autooxidation of unsaturated fatty acids (oleic, linoleic) shows that all complexes exhibit a pronounced antiradical activity. The highest effect is observed for compounds I, IV, and V characterized by the prolonged action.     

Interaction between chiral ions: synthesis and characterization of tartratovanadates(V) with tris(2,2′-bipyridine) complexes of iron(II) and nickel(II) as cations

Four new compounds composed of chiral complex cations and anions: Δ-[Fe(bpy)₃] Λ-[Fe(bpy)₃][V₄O₈((2R,3R)-tart)₂]·12H₂O (1), Δ-[Fe(bpy)₃]₂Λ-[Fe(bpy)₃]₂[V₄O₈((2R,3R)-tart)₂][V₄O₈((2S,3S)-tart)₂]·24H₂O (2), Δ-[Ni(bpy)₃]Λ-[Ni(bpy)₃][V₄O₈((2R,3R)-tart)₂]·12H₂O (3) and Δ-[Ni(bpy)₃]₂Λ-[Ni(bpy)₃]₂[V₄O₈((2R,3R)-tart)₂][V₄O₈((2S,3S)-tart)₂]·24H₂O (4) have been prepared. The compounds have been characterized by spectral methods, and their thermal decomposition was studied by simultaneous DTA, TG measurements. The final products after dynamic decomposition and additional heating were Fe₂V₄O₁₃ for 1 and 2 and Ni(VO₃)₂ for 3 and 4. The crystal structures determined for 1, 2 and 4 have evidenced that 1 is “hemiracemic” and 2 and 4 are “fully racemic” compounds.     

Synthesis and molecular and crystal structures of binuclear complexes of Sm(III), Eu(III), Gd(III), Tb(III), and Dy(III) nitrates with 4,4,10,10-tetramethyl-1,3,7,9-tetraazospiro[5.5]undecane-2,8-dione

Binuclear complexes of Sm(III), Eu(III), Gd(III), Tb(III), and Dy(III) nitrates with 4,4,10,10-tetramethyl-1,3,7,9-tetraazospiro[5.5]undecane-2,8-dione (C₁₁H₂₀N₄O₂, SC)—[Sm(NO₃)₃(SC)(H₂O)]₂(I), [Eu(NO₃)₃(SC)(H₂O)]₂ (II), [Gd(NO₃)₂(SC)(H₂O)₃)]₂(NO₃)₂ (III), [Tb(NO₃)₃(SC)(H₂O)]₂ (IV), [Dy(NO₃)₃(SC)(H₂O)]₂ (V), are synthesized, and their X-ray diffraction analyses are carried out. The crystals of complexes I–V are monoclinic: space group P2₁/n for III and P2₁/c for I, II, IV, and V. In centrosymmetric coordination complexes II, III, IV, and V, the Ln atoms are coordinated by two O(1) and O(2) atoms of two molecules of the SC ligands bound by a symmetry procedure (1 ? x, ?y, 1 ? z), three bidentate nitrate anions, and a water molecule. The coordination numbers of the metal atoms are equal to 9, and the coordination polyhedra are considerably distorted three-capped trigonal prisms, whose bases include the O(1), O(2), O(12) and O(3), O(7), O(9) atoms. The dihedral angle between the bases of the prism is 18°, and that between the mean planes of the side faces is 55°–71° for I, 17° and 55°–71° for II, 16° and 55°–70° for IV, and 16° and 55°–70° for V. The Sm...Sm distance in complex I is 9.44 Å, Eu...Eu in II is 9.42 Å, Tb...Tb in IV is 9.36Å, and Dy...Dy in V is 9.36Å. The gadolinium atom in complex III is coordinated by two oxygen atoms of two ligand molecules bound by a symmetry procedure (?x, ?y + 1, ?z + 1), two bidentate nitrate anions, and three water molecules. One of the nitro groups in compound III is localized in the external coordination sphere of the metal. The coordination number of gadolinium is 9, and the coordination polyhedron is a significantly distorted three-capped trigonal prism, whose base includes the O(1), O(2), O(7) and O(4), O(5), O(9) atoms. The dihedral angle between the bases of the prism is 22.8°, and that between the mean planes of the side faces is 53°–72°. The Gd...Gd distance in complex III is 9.17 Å.     

Syntheses and crystal structures of oxovanadium(V) complexes derived from N′-[1-(2-hydroxynaphthyl)ethylidene]-4-nitrobenzohydrazide and 2-hydroxy-N′-[1-(2-hydroxynaphthyl)ethylidene]benzohydrazide

Reactions of bis(acetylacetonato)oxovanadium(IV) with N??-[1-(2-hydroxynaphthyl)ethylidene]-4-nitrobenzohydrazide (H₂HNB) and 2-hydroxy-N??-[1-(2-hydroxynaphthyl)ethylidene]benzohydrazide (H₂HHB), respectively, product two oxovanadium(V) species with the formulas [VO(OMe)(HNB)]₂ (I) and [VO(OMe)(HHB)] (II). The complexes I and II have been characterized by elemental analysis, IR spectra, and single crystal X-ray diffraction. The crystal of I is monoclinic: space group P2₁/n, a = 8.208(2), b = 14.528(3), c = 16.418(3) ?, ?? = 97.887(3)°, V = 1939.3(7) ?³, Z = 2. The crystal of II is triclinic: space group P $P\bar 1$ a = 8.334(2), b = 10.236(2), c = 11.337(2) ?, ?? = 80.91(3)°, ?? = 75.41(3)°, ?? = 75.63(3)°, V = 902.0(3) ?³, Z = 2. Complex I is a methoxide-bridged dimeric oxovanadium(V) complex, and complex II is a mononuclear oxovanadium(V) complex. The V atom in I is in an octahedral coordination, and that in II is in a square pyramidal coordination.     

Syntheses and characterization of a new class of vanadia precursors of oxime-modified oxovanadium(V) isopropoxide,crystal and molecular structure of [VO{ONC10H16}3]

Modification of [VO(OPrⁱ)₃] with oximes in different molar ratios, yielded new class of vanadia precursors, [VO{OPrⁱ}_3?n{L}_n] {where, n = 1–3 and LH = C₉H₁₆C=NOH (1–3) and (CH₃)₂C=NOH (4–6)}.All the products are yellow in colour. (1) and (2) are liquid/viscous liquid, while others are solids. Molecular weight measurements of all these derivatives and the ESI-mass spectral studies of (1), (2), (3) and (5) indicate their monomeric nature. ¹H and ¹³C{¹H} NMR spectra suggest that the oximato moieties are monodentate in solution which was further confirmed by the ⁵¹V NMR signals, appeared in the region expected for tetra-coordinated oxo-vanadium atoms. On ageing, a disproportionation reaction occurs in (1) and some crystals appeared. Single crystal X-ray diffraction analyses of the crystals obtained from (1) as well as from (3) were found to be the same and indicate the presence of side-on {dihapto η ²-(N, O)} binding modes of the oximato ligands, leading to the formation of seven coordination environment around the vanadium atom. Thermogravimetric curve of (1) exhibits multi-step decomposition with the formation of V₂O₅ as the final product at ~850 °C. Sol–gel transformation of (3) yielded (a) VO₂ sintered at 300 °C and (b) V₂O₅ at 600 °C. Similarly, sol–gel transformations of (1) and (2) yielded V₂O₅ (c) and (d) at 600 °C, respectively. Formation of monoclinic phase in (a) and orthorhombic phase in (b), (c) and (d) were confirmed by powder XRD patterns.     

Synthesis and study of tetraamminecobalt hydrogen hexamolybdometalates(III)

Tetraamminecobalt hydrogen hexamolybdoferrate [Co(NH₃)₄] · H[FeMo₆O₁₈(OH)₆] · 6H₂O (I) and tetraamminecobalt hydrogen hexamolybdogallate(III) [Co(NH₃)₄] · H[GaMo₆O₁₈(OH)₆] · 6H₂O (II) were synthesized and studied by mass spectrometry, thermogravimetry, IR spectroscopy, and X-ray diffraction. Crystals of I and II are monoclinic; a = 16.21 Å, b = 5.43 Å, c = 12.32 Å, β = 119.63°, V = 1092.11 ų, ρ_calcd = 2.21 g/cm³, and Z = 1 for I; a = 16.24 Å, b = 5.59 Å, c = 12.29 Å, β = 119.79°, V = 1064.05 ų, ρ_calcd = 2.15 g/cm³, and Z = 1 for II. Compounds I and II were used as catalysts for soft oxidation of natural gas.     

Synthesis and Characterization of a 3-D Framework Constructed from [V12B18O54(OH)6(H2O)]10− Clusters and K+ Cations

An organic–inorganic hybrid polyoxovanadoborate K₆(CH₃NH₃)₄[V₁₂B₁₈O₅₄(OH)₆-(H₂O)]·2en·12H₂O (1, en = ethylenediamine) has been synthesized under hydrothermal conditions and characterized by IR spectroscopy, element analyses, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. Single-crystal structure analysis reveals that 1 consists of a cage-like polyoxovanadium borate [V₁₂B₁₈O₅₄(OH)₆(H₂O)]^10? cluster that is constructed from a puckered {B₁₈O₃₆(OH)₆} ring sandwiched by two triangle {V₆O₁₈} units, in which a water molecule is confined in the middle of the cage-like cluster. Interestingly, 1 represents the rare example of extended 3-D framework constructed from [V₁₂B₁₈O₅₄(OH)₆-(H₂O)]^10? clusters through K⁺ cations.     

Stability and structure in solution of potassium and barium complexes with N,N’-diaryldiaza-18-crown-6: Crystal structure of N,N’-Bis(4-dimethylaminophenyl)diaza-18-crown-6 and its complex with barium perchlorate

It has been shown that N,N’-diaryldiaza-18-crown-6 ethers with p-dimethylamino-and p-methoxy groups in the benzene ring (aryl is 4-Mc₂NC₆H₄) (I) and 4-MeOC₆H₄ (II) form complexes with potassium and barium salts. The influence of these salts on the UV and ¹H NMR spectra of crown ethers I and II has been studied. The stability constants (logβ) of the complexes increase in the series II · Ba(ClO₄)₂ (2.0), I · Ba(ClO₄)₂ (2.3), II · KBr (2.8), I · KBr (3.0). N,N’-bis(4-dimethylphenylamine)diaza-18-crown-6 (L, I) and its complex with barium perchlorate Ba(ClO₄)₂ · L (III) are characterized by X-ray crystallography. The crystals of I are monoclinic: a = 13.778(2) Å, b = 5.9731(9) Å, c = 17.542(3) Å, β = 106.65(1)°, V = 1383.1(4) ų, Z = 2, space group P2₁/n, R = 0.0374 for 990 reflections with I > 2σ(I). The crystals of III are monoclinic: a = 17.275(4) Å, b = 8.017(2) Å, c = 26.935(4) Å, β = 100.47(2)°, V = 3669(1) ų, Z = 4, space group C2/c, R = 0.0320 for 1897 reflections with I > 2σ(I). The molecules of I and III are centrosymmetric. In III, the Ba atom is in the center of substituted diaza-18-crown-6 (DA18C6). The Ba atom is coordinated by all six donor atoms of diaza-18-crown-6 (av. Ba-O, 2.779(3) Å; Ba-N, 3.004(4) Å) and four oxygen atoms of two asymmetrically bound perchlorate groups (Ba-O, 2.832(4) and 3.031(4) Å) arranged below and above the plane of substituted diaza-18-crown-6. The conformations of the macrocycle in free and coordinated L are different.     

Synthesis,crystal structures,and biological property of dinuclear oxovanadium(V) complexes derived from tridentate Schiff bases

A pair of structurally similar dinuclear oxovanadium(V) complexes, [VO₂L¹]₂ (I) and [VO₂L²]₂ (II), where L¹ and L² are the mono-anionic form of 2-[(2-isopropylaminoethylimino)methyl]-4-methylphenol (HL¹) and 4-fluoro-2-[(2-isopropylaminoethylimino)methyl]phenol (HL²), respectively, have been synthesized and characterized by elemental analysis, FT-IR spectra, and single crystal X-ray determination. The crystal of I is monoclinic: space group P2₁/c, a = 12.528(1), b = 12.266(1), c = 9.432(1) Å, β = 104.814(3)°, V = 1401.2(3) ų, Z = 2. The crystal of I is monoclinic: space group P2₁/n, a = 12.3128(5), b = 6.5124(3), c = 17.1272(7) Å, β = 105.863(1)°, V = 1321.1(1) ų, Z = 2. The V…V distances are 3.210(1) Å in I and 3.219(1) Å in II. The V atoms in the complexes are in octahedral coordination. Biological assay indicates that complex II, bearing fluoro-substitute groups, has stronger antimicrobial activity against most bacteria than complex I which bearing methyl-substitute groups.     

Synthesis and crystal structures of dimeric schiff base oxovanadium(V) complexes with antimicrobial activity

Two new dimeric oxovanadium(V) complexes, [VO₂L₁]₂ · 2H₂O (I) and [VO₂L₂]₂ (II), where L¹ and L² are the monoanionic form of 5-methoxy-2-[(2-methylaminoethylimino)methyl]phenol (HL¹) and 5-diethylamino-2-[(2-methylaminoethylimino)methyl]phenol (HL²), respectively, have been synthesized and characterized by elemental analysis, FT-IR spectra, and single crystal X-ray determination. The crystal of I is monoclinic: space group P2₁, a = 6.858(2), b = 16.630(3), c = 12.306(2) Å, β = 103.985(2)°, V = 1361.9(5) ų, Z = 2. The crystal of II is triclinic: space group $P\bar 1$ , a = 7.378(2), b = 8.838(2), c = 13.312(3) Å, α = 102.576(2)°, β = 92.044(2)°, γ = 113.017(2)°, V = 772.7(3) ų, Z = 2. The V...V distances are 3.140(1) Å in I and 3.254(1) Å in II. The V atoms in the complexes are in octahedral coordination. The effect of the complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans was studied.     

Synthesis and crystal structure of platinum(II) acetamidates [Pt(2,2′-bipy)(NHCOCH3)2] and [enPt(μ-NHCOCH3)(μ-OH)Pten](NO3)2

The diamines PtbipyCl₂, and PtenCl₂ and their aqua and hydroxy derivatives react with acetonitrile to give the Pt(II) acetamidates [Pt(2,2′-bipy)(NHCOCH₃)₂] · 4.125 H₂O (I) and [enPt(μ-NHCOCH₃(μ-OH)Pten](NO₃)₂ · H₂O (II), which are characterized by X-ray diffraction. The crystals of I are triclinic, a = 7.137(10) Å, b = 12.655(3) Å, c = 21.914(6) Å, α = 81.82(2)°, β = 82.12(2)°, γ = 77.72(2)°, V = 1908.6(7) ų, space group P $\overline 1 $ , Z = 4, R = 0.033 for 3700 reflections. Complex I is a mononuclear acetamidate with terminal (NHCOCH₃)^? ligands. The crystals of II are monoclinic, a = 11.413(2) Å, b = 10.981(2) Å, c = 14.385(3) Å, β = 105.90(3)°, V = 1733.8(6) ų, space group P2₁/n, R = 0.028 for 2797 reflections. Complex II is a dimer with bridging (NHCOCH₃)^? and (OH)^? groups. The Pt-Pt distance is 3.1667(7) Å.     

Syntheses and magnetic properties of two new tungstocobalt heteropoly acid-lanthanide complexes

Two new ionic complexes built on polyoxometalate anions of [CoW₁₂O₄₀]^6? and Ln³⁺ (Ln = Ce, Nd) cations, namely [Ce(CoW₁₂O₄₀)(NMP)₂(H₂O)₆][Ce(NMP)(H₂O)₈] · 3H₂O · NMP (I) and [Nd(CoW₁₂O₄₀)(NMP)₂(H₂O)₆][Nd(NMP)(H₂O)₈] · 7H₂O (II) (NMP = N-methyl-2-pyrrolidone) have been synthesized. Single crystal X-ray crystallographic analyses (CIF files CCDC nos. 704837 (I) and 689561 (II)) revealed that the structures of two complexes were similar, which crystallize in the P2₁/n monoclinic space group. Complexes I and II were both ionic clusters and the coordination numbers of Ln³⁺ (Ln = Ce, Nd) were nine. The unit cell parameters for I: a = 17.551(4), b = 17.783(4), c = 26.729(5) Å, β = 101.33(3)°, V = 8180(3) ų, Z = 4. The unit cell parameters for II: a = 17.571(3), b = 17.750(3), c = 28.989(9) Å, β = 115.42(2)°, V = 8166(3) ų, Z = 4. Complex I was characterized by TG analysis. Variable-temperature magnetic susceptibility measurements showed that there exists a weak antiferromagnetic interaction of complex II.     

Numerical modelling of inclusion-type complexes formed by chiral 18-crown-6 ethers bearing sugar moieties with enantiomers of phenylalanine methyl ester cations

The crystal structure of α-d-mannosido-benzo-18-crown-6·KSCN (1) was solved by X-ray single crystal diffractometry. C₂₈H₃₆O₁₀·KSCN is orthorhombic, space groupP2₁2₁2₁ withZ=4,a=8.035(4),b=9.960(2),c=38.83(2) Å,M _r =629.8,V=3103.6 ų,D _x =1.347 g cm^?3, μ(CuKα)=2.53 mm^?1, λ=1.54178 Å,F(000)=1324. FinalR=0.043 for 1139 unique observed reflections measured at room temperature. The potassium ion is surrounded by a nearly planar hexagon of oxygen atoms of the macrocyclic ring and lies on the plane formed by those atoms. Hexagonal pyramidal coordination is completed by the nitrogen atom of the thiocyanate anion. The SCN ion was found on the face of the macrocyclic ring opposite that for the chiral mannopyranoside moiety. The molecular structure of α-d-mannosido-18-crown-6 (2) and the structure of molecular complexes of2 and α-d-glucosido-benzo-18-crown-6 (3) were studied by molecular mechanics methods. The results suggest enthalpy driven selectivity of complexation of the phenylalanine methyl ester (4) by2 and both enthalpy and entropy effects in selective complexation of4 by3.     

Synthese von (5,10)-(7,8)-Bisepoxiden aus α- und β-4-Phenyl-1,2,4-triazolin-3,5-dion-Addukten von Vitamin D3 und Röntgenstrukturanalyse eines der Benzoylderivate

Oxidation of the α- and β-4-phenyl-1,2,4-triazolin-3,5-dione adducts of vitamin D₃ (2 and1) withMCPBA yields two diastereomeric mixtures of the (5,10)-(7,8)-dioxiranes3 a,3 b,3 c and4 a,4 b respectively. The corresponding benzoates5 a,5 b,6 a and6 b were prepared and the X-ray crystal structure of5 b was determined. This analysis proved5 b to be the (5R, 1 OS)-(7R, 8R)-dioxirane of the β-resp. (6S)-4-phenyl-1,2,4-triazolin-3,5-dione adduct1 of vitamin D₃.     

Crystal structures of cesium and rubidium 2-thiobarbiturates

The crystal structures of cesium 2-thiobarbiturate C₄H₃CsN₂O₂S (I) and rubidium 2-thiobarbiturate C₄H₃N₂O₂RbS (II) (C₄H₄N₂O₂S is 2-thiobarbituric acid, H₂TBA) have been determined. Isostructural crystals are monoclinic; a = 7.9609(3) Å,b = 11.8474(3) Å, c = 7.7317(2) Å, β = 101.285(3)°, V = 715.13(4) ų, space group C2/m, Z = 4 for I and a = 7.6369(2) Å, b = 11.7690(3) Å, c = 7.5568(2) Å, β = 100.212(1)°, V = 668.44(3) ų, space group C2/m, Z = 4 for II. Each metal ion in complexes I and II is bonded to four oxygen atoms and two sulfur atoms at the vertices of a six-vertex polyhedron. N-H…O hydrogen bonds link HTBA-ions into chains. The structure is also stabilized by the “head-to-tail” π-π interaction of HTBA-ions.     

Synthesis,Structure and Property of a Dawson-type Arsenomolybdate with an Appended AsIII Cap

An inorganic–organic hybrid compound, (H₂bpy)₃[As^IIIAs₂ ^VMo₁₅ ^VIMo₃ ^VO₆₂]·3H₂O (bpy: 4,4′-bipyridine) (1) has been synthesized under hydrothermal conditions and characterized by elemental analysis, X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction, IR spectrum, UV–Vis spectrum, thermogravimetric analysis and single-crystal X-ray diffraction. The crystallographic analysis reveals that compound 1 is composed of a Wells–Dawson polyoxoanion [As₂ ^VMo₁₅ ^VIMo₃ ^VO₆₂]^9? with the mixed valence of Mo^V,VI, which acts as a tetradentate ligand coordinating with the As^III cation to form the mixed valence As^III,V containing arsenomolybdate with the single cap structure in a chelate coordination mode. In the solid state, compound 1 shows a 3D supramolecular structure through hydrogen-bonding interactions (C–H···O, N–H···O, N–H···N). In addition, compound 1 exhibits reversible multi-electron redox processes and effective electrocatalytic activities towards the reduction of H₂O₂, NaNO₂ and KBrO₃. Moreover, compound 1 is used as a reducing agent of the graphene oxide to prepare graphene by a green chemistry type one-step synthesis method, which is characterized by XPS, Raman spectroscopy, PXRD, IR, scanning electron microscopy and transmission electron microscopy.     

Synthesis and study of hydrogen hexamolybdonickelate and hydrogen hexamolybdozincate with the cobaltammine cation

[Co(NH₃)₆] · H₂[NiMo₆O₁₈(OH)₆] · 6H₂O (I) and [Co(NH₃)₆] · H₂[ZnMo₆O₁₈(OH)₆] · 6H₂O (II) have been synthesized and studied by mass spectroscopy, thermogravimetry, and X-ray powder diffraction. The crystals of compounds I and II are monoclinic, Z = 1; for compound I: a = 16.10 Å, b = 5.58 Å, c = 12.22 Å, β = 117.86°, V = 1045.14 ų, and ρ_calcd = 2.26 g/cm³; for compound II: a = 16.12 Å, b = 5.52 Å, c = 12.12 Å, β = 117.90°, V = 1043.21 ų, and ρ_calcd = 2.21 g/cm³.     

Raman spectroscopy data on the phase transition of KO2 mixed with KOH on a glass fiber matrix

The composition of solid products of vacuum decomposition of K₂O₂ · 2H₂O₂ (I) on a glass fiber matrix was determined by Raman spectroscopy. The products were mainly mechanical mixtures of potassium superoxide KO₂ (II) with KOH · nH₂O (III) and, in some cases, with KOH (IV). The n value in III varies from sample to sample (most often, from 0.2 to 1). Component II is represented by the typical tetragonal phase (the ν(O-O) stretching maximum at 1146 ± 1 cm^?1). The transformation of the tetragonal phase of II into cubic phase upon sample irradiation with a focused laser beam was studied. The phase transition was initiated by increasing the power of monochromatic radiation (λ = 514.5 nm). The formation of the cubic phase was indicated by a sharp increase in the width of the ν(O-O) stretching mode. Reaching the threshold power facilitates warming up of the sample in the focusing point to ～120°C. In pure II, the phase transition is enantiotropic; when the laser radiation power drops to the initial minimal level, the tetragonal phase is formed again. When III or IV is present in the sample, this does not take place. Stabilization of the cubic phase of II is attributable to the chemical reaction with IV taking place at phase transition temperature to give a binary compound or a solid solution of the KO₂ · KOH type (V). The crystals of V correspond to the cubic system.     

Synthesis and Crystal Structure of Copper(I) Chloride π-Complexes with N-Allyl- and N,N'-Diallylpiperazinium Dichlorides: [C3H5NH(CH2)4NH2]Cu2Cl4and [C3H5NH(CH2)4NHC3H5]0.5CuCl2

The crystals of copper(I) π-complexes with N-allyl piperazine derivatives, [C₃H₅NH(CH₂)₄NH₂]Cu₂Cl₄(I) and [C₃H₅NH(CH₂)₄NHC₃H₅]_0.5CuCl₂(II), were prepared by alternating-current electrochemical synthesis. X-ray diffraction study showed that compounds Iand IIcrystallize in the monoclinic system: for I, space group P2₁/a, a= 10.254(4) Å, b= 12.306(4) Å, c= 10.656(4) Å, γ = 98.83(3)°, V= 1329(2) ų, Z= 4, R= 0.0457 for 1334 independent reflections; for II, space group P2₁/n, a= 10.187(2) Å, b= 7.283(2) Å, c= 10.480(3) Å, γ = 100.72(2)°, V= 764.0(6) ų, Z= 4, R= 0.0371 for 1025 independent reflections. The structure of Iis composed of {Cu₂Cl₄(C₇H₁₆N₂)}₂dimers linked by fairly strong (N)H···Cl hydrogen bonds (2.35(4) Å). The structure of IIconsists of centrosymmetrical dimeric Cu₂Cl₄ ^2–anions, whose copper atoms coordinate the allyl groups of different centrosymmetrical organic cations. The dimer–ligand chains are stretched along the [ $ {11} $ 0] direction and are joined by hydrogen contacts (N)H···Cl (2.62(4) Å).     

Syntheses,structures, magnetic properties,and photoluminescence of compounds Ln(2,2′-Bipy)(C4H8NCS2)3 · 0.5CH2Cl2 (Ln = Sm,Eu, Tb,Dy, and Tm)

Five compounds of the composition Ln(2,2′-Bipy)(C₄H₈NCS₂)₃ · 0.5CH₂Cl₂ (Ln = Sm (I), Eu (II), Tb (III), Dy (IV), and Tm (V); 2,2′-Bipy = 2,2′-bipyridine) are synthesized. According to the X-ray diffraction data (CIF file CCDC 986259), the crystal structure of compound I consists of molecules of the mononuclear complex [Sm(2,2′-Bipy)(C₄H₈NCS₂)₃] and solvate molecules CH₂Cl₂ (2 : 1). The coordination polyhedron N₂S₆ of the Sm atom is a distorted tetragonal antiprism. The X-ray diffraction analysis shows that compounds I–V are isostructural. The magnetic properties of compounds I–V are analyzed in the temperature range from 2 to 300 K. At 300 K compounds I and III are photoluminescent in the visible spectral range. The photoluminescence intensity of compound I considerably exceeds that of complex III.