Investigation on lanthanide binuclear complexes of 1,5-bis-(1′-phenyl-3′-methyl-5′-pyrazolone-4′)-1,5-pentanedione and 2,2′-bipyridine

The coordination of 1,5-bis-(1′-phenyl-3′-methyl-5′-pyrazolone-4′)-1,5-pentanedione (BPMPPD) and 2,2′-bipyridine (bipy) with lanthanide ions in water-alcohol solution has been studied. Binuclear complexes of the types : Ln₂(BPMPPD)₃(bipy)₂·nH₂O (n = 2 for Y, n = 4 for Eu, Gd, Dy, Ho, Er, Tm and Yb); Ln₂(BPMPPD)₃bipy·nH₂O (n = 10 for La, n = 3 for Pr, Nd, Sm and Tb) were formed. The compounds were characterized by elemental analysis, molar conductance, IR, UV, ¹H NMR spectroscopy, thermogravimetric analysis and fluorescence spectra.     

The preparation of bimetallic complexes with the ligand 1-oxy-2,6-di[N,N-biscarboxymethyl)aminomethyl]-4-chlorobenzol, and their physico-chemical characterization

With the binucleating ligand 1-oxy-2,6-di [(N,N-biscarboxymethyl)aminomethyl]- 4-chlorobenzol (H₅L) complexes of formulae FeH₂L · 2H₂O; FeH₃L(C1O₄) · H₂O; Fe₂L(OH) · 2H₂O; M₂HL · nH₂O (M = Co, Cu, n = 2; M = Ni, n = 4); FeCuL · 3H₂O; FeCrL(OH) · 3H₂O were prepared and characterized by elemental analysis, IR and electronic spectra and magnetic moment determinations. In addition, thermal analysis data of the complexes and Mössbauer effect spectra of the iron containing complexes are also given and discussed.     

Synthesis and characterization of planarly chiral nonbridged bis(1-R-indenyl) zirconium dichloride complexes and X-ray structure of rac-[(η-C9H6-1-C(CH3)2---o-C6H4---OCH3)2ZrCl2]·THF

Reactions of the lithium salts of 3-substituted indenes 1, 2 with ZrCl₄(THF)₂ gave two series of nonbridged bis(1-substituted)indenyl zirconocene dichloride complexes. Fractional recrystallization from THF–petroleum ether furnished the pure racemic and mesomeric isomers of [(η⁵-C₉H₆-1-C(R¹)(R²)---o-C₆H₄---OCH₃)₂ZrCl₂]·nTHF (R¹=R²=CH₃, n=1, rac-1a and meso-1b; R¹=CH₃, R²=C₂H₅; n=0.5 or 0, rac-2a and meso-2b), respectively. Complex 1a was further characterized by X-ray diffraction to have a C₂ symmetrically racemic structure, where the six-member rings of the indenyl parts are oriented laterally and two o-CH₃O---C₆H₄---C(CH₃)₂--- substituents are oriented to the open side of the metallocene (Ind: bis-lateral, anti; Substituent: bis-central, syn). The four zirconocene complexes are highly symmetrical in solution as characterized by room temperature ¹H-NMR, however ¹H–¹H NOESY of meso-1b shows that some of the NOE interactions arise from the two separated indenyl parts of the same molecule, which can only be well explained by taking into account the torsion isomers in solution.     

Thermochemical properties of Ln(Gly)4Im(ClO4)3·nH2O (Ln = Gd, Tb, Dy, Y)

The enthalpies of dissolution in water of new ternary complexes of four late trivalent lanthanide ions Ln(Gly)₄Im(ClO₄)₃·nH₂O (Ln=Gd, Tb, Dy, Y; Gly: glycine; Im: imidazole and n=1 or 2) were measured by means of a Calvet microcalorimeter. Empirical formulae for the calculation of the enthalpies of dissolution (Δ_dissH), relative apparent molar enthalpies (Δ_dissH (app)), relative partial molar enthalpies (Δ_dissH (partial)) and enthalpies of dilution (Δ_dilH_1,2) were obtained from the experimental data of the enthalpies of dissolution of these complexes. The plot of Δ_dissH_m^Θ, Δ_dissH (app) and Δ_dissH (partial) versus the values of the ionic radius of the lanthanide element (r) showed a grouping effect of the lanthanide elements, indicating that the coordinated bond between the lanthanide ions and the ligands has some covalent character. The unknown value of the standard enthalpy of dissolution for the similar complex: Ho(Gly)₄Im(ClO₄)₃·H₂O was estimated according to the plot of Δ_dissH_m^Θ versus r.     

Thermal cis—trans isomerization of bis(diamine) cobalt(III) and chromium(III) complexes in a solid phase

Thermal cis—trans isomerization of the simple bis(diamine) complexes [MX₂(aa or bb)₂]X · HX · n H₂O and the mixed bis(diamine) complexes [MX₂(aa)(bb)]X · HX · n H₂O was investigated in a solid phase, where M = Co(III) or Cr(III) ion, X = Cl or Br, aa and bb are one of the diamines selected from ethylenediamine (en), d, l-1,2-propane-diamine (pn), d,l-2,3-butanediamine (dl-bn), d,l-1,2-cyclohexanediamine (chxn), 1,3-propanediamine (ln) and d,l-2,4-pentanediamine (ptn), and n = 0–2. The information obtained may be summarized as follows. (1) The features of isomerization are considerably dependent upon the kind of metal ions, halide ions and diamines contained in the complexes. (2) Trans-cis isomerization was identified in the simple bis(diamine) complexes containing en, pn, dl-bn or chxn which can form five-membered chelate rings with metal ions, whereas cis-trans isomerization was detected in the simple bis(diamine) complexes containing tn or ptn which forms six-membered rings; all the mixed bis(diamine) complexes isomerize from trans to cis even when they have a combination of five- and six-membered chelate rings. (3) The cobalt(III) complexes isomerize in a temperature range of dehydration and/or dehydrohalogenation with activation energies of about 100 kJ mole⁻¹, whereas the chromium(III) complexes usually isomerize in the anhydrous state and the activation energies amount to as much as 150–190 kJ mole⁻¹. (4) “Aquation-anation” and “bond rupture” were proposed for the isomerization of the cobalt(III) and the chromium(III) complexes, respectively.     

Group 4 metallacarboranes of constrained geometries derived from B(cage)- and C(cage)-silylamido-substituted carborane ligands: a synthetic and structural investigation

The reactions of RNHSi(Me)₂Cl (1, R=t-Bu; 2, R=2,6-(Me₂CH)₂C₆H₃) with the carborane ligands, nido-1-Na(C₄H₈O)-2,3-(SiMe₃)₂-2,3-C₂B₄H₅ (3) and Li[closo-1-R′-1,2-C₂B₁₀H₁₀] (4), produced two kinds of neutral ligand precursors, nido-5-[Si(Me)₂N(H)R]-2,3-(SiMe₃)₂-2,3-C₂B₄H₅, (5, R=t-Bu) and closo-1-R′-2-[Si(Me)₂N(H)R]-1,2-C₂B₁₀H₁₀ (6, R=t-Bu, R′=Ph; 7, R=2,6-(Me₂CH)₂C₆H₃, R′=H), in 85, 92, and 95% yields, respectively. Treatment of closo-2-[Si(Me)₂NH(2,6-(Me₂CH)₂C₆H₃)]-1,2-C₂B₁₀H₁₁ (7) with three equivalents of freshly cut sodium metal in the presence of naphthalene produced the corresponding cage-opened sodium salt of the “carbons apart” carborane trianion, [nido-3-{Si(Me)₂N(2,6-(Me₂CH)₂C₆H₃)}-1,3-C₂B₁₀H₁₁]³⁻ (8) in almost quantitative yield. The reaction of the trianion, 8, with anhydrous MCl₄ (M=Ti and Zr) in 1:1 molar ratio in dry tetrahydrofuran (THF) at −78 °C, resulted in the formation of the corresponding half-sandwich neutral d⁰-metallacarborane, closo-1-M[(Cl)(THF)_n]-2-[1′-η¹σ-N(2,6-(Me₂CH)₂C₆H₃)(Me)₂Si]-2,4-η⁶-C₂B₁₀H₁₁ (M=Ti (9), n=0; M=Zr (10), n=1) in 47 and 36% yields, respectively. All compounds were characterized by elemental analysis, ¹H-, ¹¹B-, and ¹³C-NMR spectra and IR spectra. The carborane ligand, 7, was also characterized by single crystal X-ray diffraction. Compound 7 crystallizes in the monoclinic space group P2₁/c with a=8.2357(19) Å, b=28.686(7) Å, c=9.921(2) Å; β=93.482(4)°; V=2339.5(9) ų, and Z=4. The final refinements of 7 converged at R=0.0736; wR=0.1494; GOF=1.372 for observed reflections.     

Binding of acrylic and sulphonic polyanions by open-chain polyammonium cations

The interactions between some acrylic and sulphonic polyanions and some protonated amines (diamines NH₂-(CH₂)_x-NH₂, x=2,…,10; linear tri-, tetra-, penta- and hexa-amines) were studied potentiometrically in aqueous solution, at 25°C. For both types of polyanions AL₂H_i (L⁻, monomer of polyanion, A, amine) species are formed, with i=1,…,n (n=number of amino groups in the amine). The stability of these species is strictly dependent on the polyammonium cation charge, and fairly independent of the type of amine (in diamine species maximum stability is observed for x=4, 5). Acrylic and sulphonic polyanion complexes are considerably stronger than analogous species formed by low molecular weight anions. Mean stability can be expressed as log K=2.87ζ^2/3, for polyacrylic anions and log K=2.42ζ^2/3 for polysulphonic anions (ζ=absolute value for charge product of reactants).     

Transition metal complexes with long-chain amines thermal behaviour and crystal structure of (n-CaH2a+1NH2)2ZnCl2

The thermal behaviour of (n-C_aH_2n+1NH₂)₂ZnCl₂ complexes with n = 6, 8, … 16 has been investigated by DSC and by temperature variable IR and X-ray powder diffraction techniques. Complexes with n = 12,14,16 show solid—solid phase transition which are “melting” transitions of the hydrocarbon regions of the structure. The crystal structure of both the low and the high temperature polymorphs is characterized by the piling of sandwiches, each formed by an “inorganic” layer sandwiched between two alkylammonium layers.     

La-NMR-spektroskopie an allyllanthan(III)-komplexen

¹³⁹La-NMR chemical shifts were measured for several anionic complexes of formulae Li(C₄H₈O₂)_3/2 [La(ν³-C₃H₅)₄], [Li(C₄H₈O₂)₂][Cp′_nLa(ν³-C₃]H₅)_4−n] (Cp′ = Cp(ν⁵-C₅H₅); n = 1, 2 and Cp′ = Cp * (ν⁵-C₅Me₅); N = 1) and Li[R_nLa(ν³-C₃H₄)₄−n] (R = N(SiMe₃)₂; n = 1, 2 and R = CCsIMe₃; n = 4), as well as for neutral compounds for formulae La(ν³-C₃H₅)₃L_n (L = (C₄H₈O₂)_1.5, (HMPT)₂, TMED), Cp′_nLa(ν³-C₃H₅)_3−n (Cp′= Cp(ν⁵-Cp₅H₅), Cp *(ν⁵-C₅Me₅); n = 1, 2) and La(ν³-C₃H₂)₂X(THF)₂ X = Cl, Br, I). Typical ranges of the ¹³⁹La-NMR chemical shifts were found for the different types of complex independent of number and kind of organyl groups directly bonded to lanthanum.

Zusammenfassung

¹³⁹La-NMR-Spektroskopie wurde an einer Reihe anionischer Allyllanthanat(III)-Komplexe der Zusammensetzung ]- [La)ν³-C₃H₅)₄, [Li(C₄H₈)₂][Cp′_nLa(ν³-C₃H₅)_4−n(Cp′ = Cp(ν⁵-C₅H₅); n = 1, 2 und Cp′ = Cp * (ν⁵-C₅Me₅); N = 1) und Li[R_nLa(ν³-C₃H₅)_4−n (R = B(SiMe₃)₂; n = 1, 2 und R = CCSiMe₃; n = 4 sowie neutraler Allyllanthan(III)-Komplexe der Zusammensetzung La(ν³-C₃H₅)₃L_n (L_n = (C₄H₈O₂)_1.5, (HMPT)₂, TMED), Cp′_n, La(ν³-C₃H₅)_3−n (Cp′ = Cp(ν⁵-C₅H₅), Cp * (ν⁵- Cp₅Me₅); n = 1, 2) und La(ν³-Cp₃H₅)₂X(THF)₂ (X = Cl, Br, I) durchgefürt. In Abhängikeit von der Anzahl und der Art der am Lanthan gebundenen Gruppen wurden für die verschieden Komplextypen charakteristische Resonanzbereiche ermittelt.     

Complexes of cationic coinage metal clusters Mn (M=Cu, Ag, Au; n=1–4) and H2S: a theoretical study

Geometries and vibrational frequencies of complexes of cationic coinage metal clusters M_n⁺ (M=Cu, Ag, Au; n=1–4) and H₂S are computed using density functional theory. Thermochemical values for M_n⁺H₂S decomposition channels involving loss of an H atom, H₂ molecule, M atom, or M₂ molecule are also computed. Significantly different results are obtained for closed-shell (n odd) and open-shell (n even) complexes.     

Reactions of cyclo-(t-Bu4Sb4) with alkali metals; syntheses and crystal structures of [M(L)n(t-Bu4Sb3)] (M=Na, K; n=1, 2) and [K(L)(t-Bu3Sb2)] (L=(Me2NCH2CH2)2NMe)

Reduction of cyclo-(t-Bu₄Sb₄) (1) with sodium or potassium in boiling tetrahydrofuran leads to the anions [t-Bu₄Sb₃]⁻ and [t-Bu₃Sb₂]⁻. Crystallization with pentamethyldiethylenetriamine (L) gives [M(L)_n(t-Bu₄Sb₃)] (n=1, M=Na (2), K (3); n=2, M=K (4)) and [K(L)(t-Bu₃Sb₂)] (5). Crystal structure analyses reveal coordination of the anionic antimony ligands on the alkali metal ions for 2, 3, and 5. In contrast, no Sb---K interactions were observed in the structure of 4.     

Heterobimetallic Mo---Sn complexes. Reactions of [Mo(CO)3(CH3CN)2(Cl)(SnRCl2)] (R = Me, Ph) with 4(4-XC6H4)3 (X = Cl, F, H, Me, MeO)

Three families of heterobimetallic compounds were obtained by reaction of [Mo(CO)₃(CH₃CN)₂(Cl)(SnRCl₂)] (R = Ph, Me) with P(4-XC₆H₄)₃ (X = Cl, F, H, Me, MeO). The type of compound obtained dependent on the solvent and concentration of the starting compound. So, [Mo(CO)₂(CH₃COCH₃)₂(PPh₃)(Cl)(SnRCl₂)]·nCH₃COCH₃ (R = Ph, n = 0.5; R = Me, n = 1) (type I) and [Mo(CO)₃{P(4-XC₆H₄)₃}(μ-Cl)(SnRCl₂)]₂ (R = Ph, X = Cl, F, H, Me, MeO; R = Me, X = Cl, F) (type II) were isolated from acetone solution in ca 0.05 M and 0.1 M concentrations, respectively. However, [Mo(CO)₃(CH₃CN) {P(4-XC₆H₄)₃}(Cl)(SnRCl₂)] (R = Ph, X = H; R = Me, X = Cl, F, H) (type III) were obtained from dichloromethane solution independently of the concentration used. All new complexes showed a seven-coordinate environment at molybdenum, containing Mo---Cl and Mo---Sn bonds. Mössbauer spectra indicated a four-coordination at tin for type III complexes.     

Density functional theory analysis of CaRgn complexes: (Rg=He, Ne, Ar; n=1–4)

CaRg_n⁺ (Rg=He, Ne, Ar) complexes with n=1–4, are investigated by performing using the B3LYP/6-311+G (3df) density functional theory calculations. The CaHe_n⁺ (n=1–4) complexes are found to be stable. In the case of CaNe_n⁺ and CaAr_n⁺, stable structures and stationary point were found only for n=1 and 2. For n=3 in the C_3V and the D_3h point group as well as for n=4 in the T_d (tetrahedral) point group a saddle point (imaginary frequency) is observed and global minimum could be obtained along the potential energy surface.     

开放骨架磷酸铝合成中碳链长度对乙二胺结构导向效应的影响

以乙二胺(EDA)和1,3-丙二胺(1,3-DAP)为结构导向剂,在180 ℃加热摩尔比n(Al₂O₃):n(P₂O₅):n(R):n(H₂O)=1:1:1:277(R=EDA,1,3-DAP)的混合物,分别得到了高结晶度的三维阴离子开放骨架磷酸铝AlPO₄-12和UiO-26。 利用X射线粉末衍射分析、元素分析和液相酸碱度测量等表征手段,研究了两个合成体系的晶化过程以及晶化过程中液相的Al、P浓度和pH值随时间的演化。 用Materials Studio中的“原子体积和表面”模块和Dmol3模块计算了双质子化乙二胺和1,3-丙二胺的体积以及Hirshfeld电荷。 结果表明,双质子化EDA和1,3-DAP中N原子上的Hirshfeld电荷分别为0.073 e和0.064 e,按Hirshfeld电荷计算的电荷密度分别为1.8573和1.3400 e/nm³,按形式电荷计算的电荷密度分别为25.44和20.94 e/nm³,而AlPO₄-12和UiO-26的骨架电荷密度分别为-6.1和-4.6 e/nm³。 结果表明,与氨基中N原子相连碳链长度的改变会影响其上的电荷量以及电荷密度,从而改变原有机胺的结构导向效应,导致晶化产物从AlPO₄-12变成了具有较小电荷密度的UiO-26。     

Gas-phase stability of cluster ions SF m + (SF6) n with m = 0–5 and n = 1–3

The gas-phase stabilities of cluster ions SF⁺_m (SF₆)_n with m = 0−5 were determined by using a high pressure mass spectrometer. The bond energies of SF⁺_m (SF₆)₁ were found to be less than 10 kcal/mol and to decrease with m = 0 → 5. There appear to be rather large gaps in the bond energies between n = 1 and 2 for the clusters SF⁺_m (SF₆)_n with m = 0−4. The structures of SF⁺₅, SF⁺ (SF₆)₁, SF⁺₃ (SF₆)₁, and SF⁺₅ (SF₆)₁ were investigated by ab initio molecular orbital calculations. For SF⁺₅, the D_3h geometry is found to be most stable andC_4v is a transition state of the Berry pseudorotation. For the ion-molecule complexes, the “on-top hat” models were found to be the most stable structures.     

卤代芳香族羧酸与含氮配体合成镧系配合物的结构、热化学和荧光性质（英文）

采用室温溶液挥发法合成了五种结构新颖的镧系配合物,其结构通式为[Ln(2,4-DFBA)₃(phen)]₂ (Ln=Sm 1, Eu2, Er 3, 2,4-DFBA为2,4二氟苯甲酸的简写,phen为1,10-菲啰啉的简写),[Ln(2-Cl-6-FBA)₂(terpy)(NO₃)(H₂O)]₂ (Ln=Tb4, Dy 5, 2-Cl-6-FBA为2-氯-6-氟苯甲酸的简写, terpy为2,2’:6’2’’-三联吡啶的简写)。五个配合物可以分为两个系列,使用不同的镧系离子作为中心离子。通过X射线单晶分析,5种配合物均属于单斜晶系,空间群为P21/n。配合物1,2和配合物3虽然具有相同的分子通式,但配位方式明显不同,形成了前者为9配位的松饼型,后者是8配位的双帽三棱柱几何构型。二维面状超分子结构的形成方式也明显不同,区别在于配合物1和2通过微弱的π-π堆积作用形成。配合物4和5是同构的,结构中引入了硝酸根离子较为有趣,通过C―H···F氢键和π-π堆积作...     

Synthesis and characterisation of nickel(II) complexes with tripodal ligand tris[4-(3-(5-methylpyrazolyl)-3-aza-3-butenyl] amine (MPz3tren): X-ray crystal structure of [Ni(MPz3tren)](BF4)2·0.5H2O

Nickel(II) complexes of the tripodal ligand (MPz₃tren) of the general formula [Ni(MPz₃tren)]X₂·nH₂O (X=Cl, Br, NO₃, ClO₄ and BF₄; n=0 for Cl and Br; n=0.5 for NO₃, ClO₄ and BF₄) have been prepared by template methodology and characterised by elemental analyses, magnetic susceptibility and conductivity measurements at RT, IR and electronic spectra. The molar conductivities measured in MeOH for all the complexes show them to be 1:2 electrolytes. The hexadentate character of the ligand in all the complexes is inferred from IR spectral studies. The electronic spectra in solid state and in MeOH solution suggest octahedral geometry for all the complexes. The structure of [Ni(MPz₃tren)](BF₄)₂·0.5H₂O has been determined by single-crystal X-ray diffraction studies (monoclinic, c2/c). Nickel(II) is in a trigonal antiprismatic N₆ donor environment and the crystal structure is stabilised by a network of strong H-bonding.     

Iminophosphine-palladium(0) complexes as catalysts in the alkoxycarbonylation of terminal alkynes

In the presence of methanesulfonic acid, the palladium(0)-olefin complexes: [Pd(η²-ol)(P---N)] [ol=dimethyl fumarate or fumaronitrile, P---N=1-(Ph₂P)C₆H₄-2-CH=NR (R=CMe₃ or C₆H₄OMe-4)] catalyse the alkoxycarbonylation of terminal alkynes. Moderately good rates are obtained when the catalysts are promoted with two equivalents of the free P---N ligand and a large excess of acid at 120°C. The catalytic data suggest that derivatives of the type [Pd(alkyne)(P---N)_n] (n=2–3) are the active catalytic species.     

苯胺基桥联双芳氧基稀土金属配合物的合成、表征及催化性能

通过配体前体苯胺基桥联双酚（PhN｛CH₂-（2-HO-C₆H₂-B{\mathrm{u}}_{\mathrm{2}}^t-3,5）｝₂,L¹H₂）与三硅胺基稀土金属配合物的质子交换反应,合成了苯胺基桥联双芳氧基稀土金属配合物,发现反应介质对反应的产物有明显的影响。L¹H₂与Ln［N（TMS）₂］₃（μ-Cl）Li（THF）₃以物质的量比1∶1在甲苯中90 ℃下反应,可以得到预期的苯胺基桥联双芳氧基稀土金属胺化物L¹LnN（TMS）₂（THF） （Ln=Yb（1）,Sm（2））。而L¹H₂与Sm［N（TMS）₂］₃（μ-Cl）Li（THF）₃以1∶1的物质的量比在四氢呋喃（THF）中50 ℃下反应,则得到钐-锂杂双金属配合物（THF）LiL¹₂Sm （3）。这些配合物均经过了红外光谱、元素分析和单晶结构测定的表征。发现配合物1和2可以有效地催化L-丙交酯和D,L-丙交酯的开环聚合,得到高相对分子质量的聚丙交酯。其中,配合物1对D,L-丙交酯的开环聚合显示很好的选择性,可以得到杂同含量（Pr）达到0.87的聚丙交酯。     

Spectroscopic and structural studies on metal halide complexes of 4-vinylpyridine

Fourier transform infrared spectra (4000–400 cm⁻¹) are reported for metal(II) halide 4-vinlypridine complexes of the following stoichiometries: [MX₂(4-vipy]_n (n=4, M=Ni, X=Cl or Br; n=2, M=Cd, X=Cl, Br or I) and assignment are given for all the observed bands. These spectra were compared with X-ray powder diffraction patterns of complexes. It is shown that the proposed structures for these complexes derived from FTIR spectra are consistent with the X-ray powder diffraction measurements and the elemental analysis results. Coordination effect on 4-vinylpyridine has also been investigated.