Structure and thermal properties of volatile copper(II) complexes with β-diimine derivatives of acetylacetone and the structure of 2-(methylamino)-4-(methylimino)-pentene-2 crystals

Copper(II) chelates with β-diimine derivatives of acetylacetone that have a general formula of Cu(R¹C(NR²)CHC(NR²)R¹)₂, where R¹, R² are alkyl substituents, are synthesized. The complexes were identified using elemental analysis, melting point measurements, and high-temperature mass spectrometry data. Knudsen technique is employed to determine the vapor pressure temperature dependence, and standard thermodynamic parameters of sublimation ΔH _T ⁰ and ΔS _T ⁰ are derived. A single crystal X-ray diffraction study is carried out for copper(II) complexes of Cu(CH₃-C(NCH₃)-CH-C(NCH³)-CH₃)₂ (a = 10.363(1) Å, b = 11.978(1) Å, c = 12.653(1) Å, V = 1570.6(3) ų, space group Pnc2, Z = 4, d _calc = 1.328 g/cm³, R = 0.027), Cu(CH₃-C(NC₂H₅)-CH-C(NC₂H₅)-CH₃)₂ (a = 11.782(4) Å, b = 13.951(8) Å, c = 25.591(8) Å, V = 4206(3) ų, space group C222¹, Z = 8, d _calc = 1.169 g/cm³, R = 0.10), and also 2-(methylamino)-4-(methylimino)-pentene-2 CH₃-(C=(NCH₃))-CH=(C-(NHCH₃))-CH₃ (a = 12.129(2) Å, b = 12.034(2) Å, c = 5.692(1) Å, β = 107.05(3)°, V = 794.3(3) ų, space group Cc, Z = 4, d _calc = 1.055 g/cm³, R = 0.06). Van der Waals lattice energy E _cryst is calculated for the cooper(II) complexes by the atom-atom potential technique. The calculated values are compared to experimental sublimation enthalpies Δ H _T ⁰ .     

The Inclusion Mode of tert-Butylbenzene in the 1-D Channel of Microporous β-Bis(1,1,1-trifluoro-5, 5-dimethyl-5-methoxy-acetylacetonato) copper(II)

Inclusion of tert-butylbenzeneinto the l-D channel of the titlehost matrix results in a-[CuL₂]1/3(tert-butylbenzene)inclusion compound(trigonal, space groupR =3;a = 24.495(3),c = 10.510(2) Å,V = 5461(1) ų,Z = 9;R = 0.049). The observed guest–host mole ratio of 1/3 was confirmed by X-ray diffraction and arises from the stoichiometric filling of the larger wide segments of the channel. This contrasts with the benzene inclusion compound studied previously, where both the larger and smaller wide segments were occupied to give a 2/3 guest–host stoichiometry. A comparison of these two structures explains the experimental fact that the guest–host mole ratios for inclusions of the title host lie between values of 1/3 and 2/3for 20 different benzene derivatives.     

Thermal Properties of Cobalt(II) β-Iminoketonates

Russian Journal of General Chemistry - Thermogravimetry, differential scanning calorimetry, and flow methods were used to investigate thermal properties of a series of cobalt(II)...     

Mechanism of electrochemical synthesis of copper(II) β-diketonates

Formation of copper -diketonates in electrolysis of a solution of acetylacetone in acetonitrile in the presence of oxygen, with tetraethylammonium bromide as supporting electrolyte, was studied.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 11, 2004, pp. 1804–1807.Original Russian Text Copyright © 2004 by Kostyuk.     

Vapor pressure and crystal lattice energy of volatile palladium(II) β-iminoketonates

Volatile palladium(II) β-iminoketonates of the general formula Pd(R–C(NH)–CH–CO–R¹),where R and R¹ are CH₃, CF₃, C(CH₃)₃ in various combinations, were synthesized and identified. Thermal properties of the resulting palladium(II) complexes in the solid phase were studied by thermogravimetric analysis under an argon atmosphere. The temperature dependence of the saturated vapor pressure was measured for the compounds by the flow method and thermodynamic characteristics of vaporization processes, enthalpy ΔH _T and entropy ΔS _T^o, were determined. The atom-atomic potential calculation of the van der Waals energy (E _cryst) of the crystal lattice was performed and the results were compared to the experimental values of the sublimation enthalpy for the complexes under study.     

Complexes of copper(II) with the β-blocker atenolol

Mono- and binuclear copper(II) complexes with atenolol (HAt) can be obtained, depending on the reaction conditions. The mononuclear violet complex cation has the general formula Cu(HAt)₄ ²⁺ with an elongated octahedral geometry. The two ligands in the equatorial plane are bound in a bidentate fashion through the hydroxyl oxygen and amino nitrogen, while the other two atenolol molecules in axial position are coordinated in a monodentate way. The binuclear green complex Cu₂At₂Cl₂, is neutral, where atenolol acts as a bidentate (O^–, NH) bridging ligand. The bridge between the two Cu atoms is realized by the deprotonated oxygen of the alcohol group.     

Study of liquid-crystalline copper(II) β-enaminoketonates by EPR

The structure of the chelate unit and magnetic properties of the homologous series of liquid-crystalline bis{1-[4-(4-alkoxybenzoyloxy)phenyl]-3-amyl-1-aminoprop-1-en-3-onate)copper(II) complexes was studied by EPR. The direction of the orientation of liquid crystal molecules in an external magnetic field in the mesophase state was determined. The complexes have a square-planar structure of the chelate unit determining their mesomorphic properties.     

Protolytic properties and complexation with copper(II) ions of some azo derivatives of β-arylaminopropionic acids

The azo coupling reaction of N-(2-carboxyethyl)anthranilic acid and N,N,N′,N′-tetrabis(2-carboxyethyl)-1,3-phenylenediamine with diazosulfanilic acid yielded the complexones sodium 4-N-(2-carboxyethyl)amino-5-carboxyazobenzene-4′-sulfonate (I) and 2,4-N,N,N′,N′-tetrabis(2-carboxyethyl)diaminoazobenzene-4′-sulfonic acid (II), respectively. The acidity constants of I and II (20°C, μ = 0.1M KCl) were determined to be as follows: for I, pK ₀₀ = 1.29 ± 0.13, pK ₀ = 2.92 ± 0.07, pK ₁ = 3.92 ± 0.05, pK ₂ = 5.16 ± 0.03; for II, pK ₀₀ = 2.35 ± 0.06, pK ₀ = 2.81 ± 0.09, pK ₁ = 3.21 ± 0.11, pK ₂ = 3.81 ± 0.09, pK ₃ = 4.34 ± 0.04, pK ₄ = 5.03 ± 0.06, pK ₅ = 6.67 ± 0.07. The electronic absorption spectra of I and II were measured, and acid-base equilibrium scheme for I and II in aqueous solutions were suggested. The complexation constants of I and II with copper(II) ions were determined to be logK _CuQ^I= 5.47 ± 0.06 and logK _CuQ^II= 5.72 ± 0.13 (20°C, μ = 0.1 M KCl).     

Synthesis and magnetic properties of copper(II)-cobalt(II) complexes ofN,N′-1,2-propanedisalicylamidatocuprate(II)

Summary The binuclear metal complexes [Cu(sampn)Co(L)₂] (L=bipy, phen), have been prepared by the reaction of sodiumN,N-1,2-propanedisalicylamidatocuprate(II) heptahydrate, Na₂[Cu(sampn)] 7H₂O, with a divalent metalion, and 2,2-bipyridine or 1, 10-phenathroline. The complexes were characterized by variable-temperature magnetic susceptibility measurements; the results indicate that a weak antiferromagnetic spin-exchange interaction operates between the metal ions.     

Structure and properties of α-AgFe2(MoO4)3

Silver diiron tris(oxomolybdate), α-AgFe₂(MoO₄)₃, was synthesized in sealed silica tubes at 1050 K and is isostructural to α-NaFe₂(MoO₄)₃, determined by single-crystal X-ray diffraction (space group P?1, a = 6.9320(7) Å, b = 6.9266(6) Å, c = 10.9732(13) Å, α = 81.197(8)°, β = 83.456(9)°, γ = 81.352(8)° at 300 K, Z = 2). The crystal structure is built up from both monomers and edge-sharing dimers of [FeO₆]-octahedra, which are linked with each other by isolated [MoO₄]-tetrahedra to a three-dimensional network. Ag ions are situated on a site with four near oxygen neighbours. Thermal expansion is most pronounced along the c-axis, while the angle α decreases with increasing temperature. Antiferromagnetic ordering is indicated by a sharp maximum in the temperature dependence of magnetization at 21.5(5) K, and a magnetic moment of 5.36(1) μ_B per Fe-ion was derived from the Curie constant in the paramagnetic region. The collinear antiferromagnetic structure with propagation vector k = (0,½,½) and an ordered magnetic moment of 4.62(9) μ_B per Fe-ion were deduced from neutron powder diffraction data and give evidence for an underlying magnetic interaction mechanism, resulting in rather strong and long-ranged couplings. Mössbauer spectroscopy shows a change in the electronic configuration on the two distinct Fe sites between room temperature and 150 K, accompanied by an increase of the average Fe–O distance for one site and a shrinking one for the other as expected for charge ordering in a mixed valence compound with Fe(II) and Fe(III).     

Thermal properties of hafnium(IV) and zirconium(IV) β-diketonates

Five volatile hafnium(IV) and zirconium(IV) β-diketonates: hafnium(IV) acetylacetonate, hafnium(IV) trifluoroacetylacetonate, hafnium(IV) pivaloyltrifluoroacetonate, hafnium(IV) 2,2,6,6-tetramethylheptane-3,5-dionate and zirconium(IV) 2,2,6,6-tetramethylheptane-3,5-dionate were obtained, purified and identified. Thermal behavior of solid compounds was investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC) in helium atmosphere and in vacuum. DSC method was also used for definition of thermodynamic characteristics of melting processes. Using the static method with quartz membrane zero-manometer and the flow method the temperature dependencies of saturated vapor pressure for hafnium(IV) complexes was obtained. The standard thermodynamic characteristics ΔH _T⁰ and ΔS _T⁰ of sublimation and evaporation processes were calculated from the temperature dependences of saturated vapor pressure.     

Structure and properties of a heterocomplex compound based on lead(II) hexafluoroacetyl acetonate and copper(II) trifluoroacetyl acetonate Cu(tfa)2·Pb(hfa)2

The crystals of a heterobimetallic complex based on lead(II) hexafluoroacetyl acetonate and copper(II) trifluoroacetyl acetonate were investigated by X-ray diffraction. Crystal data for Cu(tfa)₂·Pb(hfa)₂: a = 9.3991(4) Å, b = 11.7816(5) Å, c = 13.9736(5) Å, α = 88.311(2)°, β = 89.972(1)°, γ = 76.326(1)°, space group P-1, Z = 2, d _calc = 2.190 g/cm³. The basic structural motif for the complexes is coordination polymer in the form of chains of alternating complex molecules. The Cu(tfa)₂ molecules have a trans configuration. The results of a DTA-TG analysis of the compound are given.     

Structure of the hexanuclear Cu(II) β-diketonate complex

The structure of the hexanuclear copper(II) β-diketonate complex with gfa (hexafluoroacetylacetone) and dpm (dipivalylmethanate) ligands was studied by low-temperature (T = 100 K) X-ray diffraction. Crystal data for Cu₆(gfa)₄(dpm)₄(OH)₄ [C₆₄H₈₄Cu₆F₂₄O₂₀]: a = 28.2364(7) Å, b = 12.8072(3) Å, c = 24.7199(7) Å, β= 115.900(1)°, V = 8041.5(4) ų, space group C2/m, Z = 4, d _calc 1.661 g/cm³. The coordination polyhedra of the copper atoms — squares and octahedra — are formed by the oxygen atoms of the gfa and dpm ligands and groups. In all cases, the Cu-O distances vary from 1.89 Å to 2.13 Å. The complexes follow the sites of the rhombohedral sublattice with the parameters a _c ≈ 14.4 Å and a _c ≈ 61.5°.     

Transesterification of copper(II) β-ketoesterates and acylpyruvates with borneol

Transesterification of copper(II) acetoacetates, copper(II) trifluoroacetoacetate, and copper(II) acylpyruvates with borneol gives the copper(II) chelates of the corresponding bornyl esters in 92–95 % yields. Bornyl acetyl- and perfluoroacylpyruvates were synthesized for the first time by decomposing the respective chelates with hydrogen chloride. Bornyl acylpyruvates react with hydrazine hydrate to give 5-alkyl-3-bornyloxycarbonylpyrazoles.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 902–904, May, 1993.     

Synthesis and properties of double copper(I)–nickel(II) sulfite

Pourbaix diagrams of Cu–H₂SO4–H₂O and Ni–H₂SO₄–H₂O systems have been refined, and stability regions of the sulfite phases have been determined. State diagrams of double copper(I)–copper(II) and copper(I)–nickel(II) sulfites have been constructed. Double copper(I)–nickel(II) sulfite has been isolated from aqueous solutions saturated with sulfur dioxide. The solutions at different ratios of the metals have been studied by spectrophotometry; the isolated double sulfite has been studied by X-ray diffraction, IR spectroscopy, dispersion analysis, and thermal analysis. Fundamentals of thermodynamic prognostication of the Cu₂SO₃·MSO₃ double sulfites synthesis have been elaborated.     

Synthesis of volatile copper(II) β-diketonates, β-ketiminates, and β-diiminates. The problem of synthesis of copper(II) Bis(2,2,6,6-tetramethyl-3-methylaminoheptane-5-onate)

The methods of synthesis of the copper(II) β-diketonates, β-ketiminates, and β-diiminates containing in the composition CH₃, CF₃, C(CH₃)₃, and Ph substituents were summarized. At the formation of metallocycles with 2,2,6,6-tetramethyl-3-methylaminoheptane-5-one ligand the intraligand repulsion of tret-butyl group and the methyl group at the nitrogen atom is noted, impeding the complexation.     

Crystal Structure of 2-(4-Fluorophenylamino)-2-thiomethyl acetophenone

1mThODUCTIONThioacetalshavebeenwellstudied,becauseoftheirapplicationsinorganicsyn-thesist1i.However,aketohemithioacetalshaveseldombeeninvestigated.Inthispa-Per,wediscussedthecrystalstructureofthetitlecompoundsynthesizedbythereac-tionofabenzoylhemithioacetal(2-hydroxy-2-thiomethylacetoPhenone)and4-fluthroaniline.Sinceknowledgeofthemolecularandcrystalstructureofthetitlecom-PoundwasconsideredusefulforunderstandingthemechanismofthereactionandchemicalproPertiesofaketohemithioacetal,theX-raycr…