Komplexe von FeI2 und FeI3 mit Tetramethylharnstoff

Complexes of FeI₂ and FeI₃ with Tetramethylurea [FeI₂(OC(NMe₂)₂)₂] ( 1 , [Fe₂I₄(OC(NMe₂)₂)₂] ( 2 ), and [FeI₃(OC(NMe₂)₂] ( 3 ) were prepared by the reaction of FeI₂ and FeI₂/iodine, respectively, with tetramethylurea. The structures of 1 and 3 were determined from single crystal X-ray diffraction data. 1 crystallizes in the triclinic space group P1 , with a = 809.9(1), b = 923.2(1), c = 1 374.6(1) pm, α = 106.80(1), β = 90.47(1), γ = 101.55(1)°; Z = 2; R = 0.045., 3 : monoclinic, P2₁/c, a = 1 311.4(1), b = 783.3(1), c = 1 409.1(1) pm, β = 97.36(1)°; Z = 4; R = 0.047. 1 and 3 are isolated neutral complexes with distorted tetrahedral coordination of iron. 3 is the first FeI₃-complex with an O-donor ligand. The IR-spectra exhibit strong shifts of n?C = O and n?_asC—N of tetramethylurea especially on coordinating to FeI₃.     

Synthesis of Inorganic Structural Isomers By Diffusion‐Constrained Self‐Assembly of Designed Precursors: A Novel Type of Isomerism

The structure of precursors is used to control the formation of six possible structural isomers that contain four structural units of PbSe and four structural units of NbSe₂: [(PbSe)_1.14]₄[NbSe₂]₄, [(PbSe)_1.14]₃[NbSe₂]₃[(PbSe)_1.14]₁[NbSe₂]₁, [(PbSe)_1.14]₃[NbSe₂]₂[(PbSe)_1.14]₁[NbSe₂]₂, [(PbSe)_1.14]₂[NbSe₂]₃[(PbSe)_1.14]₂[NbSe₂]₁, [(PbSe)_1.14]₂[NbSe₂]₂[(PbSe)_1.14]₁[NbSe₂]₁[(PbSe)_1.14]₁[NbSe₂]₁, [(PbSe)_1.14]₂[NbSe₂]₁[(PbSe)_1.14]₁[NbSe₂]₂[(PbSe)_1.14]₁[NbSe₂]₁. The electrical properties of these compounds vary with the nanoarchitecture. For each pair of constituents, over 20 000 new compounds, each with a specific nanoarchitecture, are possible with the number of structural units equal to 10 or less. This provides opportunities to systematically correlate structure with properties and hence optimize performance.     

Monomer-isomerization polymerization. XI. Monomer-isomerization copolymerizations of 2-butene with 2-pentene and 2-hexene with Ziegler-Natta catalyst

2-Pentene and 2-hexene were found to undergo monomer-isomerization copolymerizations with 2-butene by Al(C₂H₅)₃–VCl₃ and Al(C₂H₅)₃–TiCl₃ catalysts in the presence of nickel dimethylglyoxime or transition metal acetylacetonates to yield copolymers consisting of the respective 1-olefin units. For comparison, the copolymerizations of 1-pentene with 1-butene and 1-hexene with 1-butene by Al(C₂H₅)₃–VCl₃ catalyst were also attempted. The compositions of the copolymers obtained from these copolymerizations were determined by using the calibration curves between the compositions of the respective homopolymer mixtures and the values of D₇₆₆/D₁₃₈₀ in the infrared spectra. The monomer reactivity ratios for the monomer-isomerization copolymerizations of 2-butene (M₁) with 2-pentene and 2-hexene, in which the concentrations of both 1-olefins calculated from the observed isomer distribution were used as those in the monomer feed mixture, and for the ordinary copolymerizations of 1-butene (M₁) with 1-pentene and 1-hexene by Al(C₂H₅)₃-VCl₃ catalyst were determined as follows: 2-butene (M₁)/2-pentene (M₂): r₁ = 0.14, r₂ = 0.99; 1-butene (M₁)/1-pentene (M₂): r₁ = 0.30, r₂ = 0.74; 2-butene (M₁)/2-hexene (M₂): r₁ = 0.11, r₂ = 0.62; 1-butene (M₁)/1-hexene (M₂): r₁ = 0.13, r₂ = 0.90.     

TiO2基态和激发态的几何结构、激发能和偶极矩

采用二阶微扰理论MP2、密度泛函B3LYP方法和含时密度泛函TD-B3LYP方法分别优化了TiO₂分子的基态¹A₁和六个激发态¹B₂、³B₂、¹B₁、³B₁、¹A₂和³A₂的几何结构. ¹A₁、¹B₂、³B₂、¹B₁和³B₁具有弯曲几何结构, ¹A₂和³A₂具有线性对称结构. 我们发现激发态¹B₂、³B₂、¹B₁和³B₁键偶极矩的数值大小顺序和相应的键角大小顺序完全一致. 另外, 采用完全活化空间自洽场(CASSCF)CASSCF(6,6)、CASSCF(8,8)、多参考组态相互作用(MRCI)和含时密度泛函TD-B3LYP 计算了TiO₂ 分子各激发态的垂直激发能和绝热激发能. 对¹B₂、³B₂和¹B₁三个态, MRCI/CASSCF(6,6) 计算的垂直激发能和绝热激发能与已有的实验值最接近. 对其他三个激发态³B₁、¹A₂和³A₂, 计算的激发能和文献报道的激发能计算值基本一致. 最后, 还计算了TiO₂分子的基态和激发态的偶极矩. 对¹A₁和¹B₂态, 偶极矩的计算值与已有的实验值相吻合. 采用原子偶极矩校正的Hirshfeld 布居方法计算了TiO₂分子在¹A₁、¹B₂、³B₂、¹B₁和³B₁态时各原子的电荷, 发现从基态到激发态偶极矩的变化与电荷从氧原子向钛原子的转移有关. 整个计算中还考察了基函数cc-pVDZ、cc-pVTZ和cc-pVQZ对计算结果的影响.     

Synthese und Kristallstrukturen der Phosphaniminato-Komplexe [AlCl2(NPEt3)]2, [GaI2(NPEt3)]2 und [GaI2(NPPh3)]2

Synthesis and Crystal Structures of the Phosphoraneiminato Complexes [AlCl₂(NPEt₃)]₂, [GaI₂(NPEt₃)]₂, and [GaI₂(NPPh₃)]₂ [AlCl₂(NPEt₃)]₂ ( 1 ) is made according to the known method by reaction of aluminium trichloride with the silylated phosphaneimine Me₃SiNPEt₃ in acetonitrile; it is isolated as colourless, moisture sensitive crystals. The phosphoraneiminato complexes [GaI₂(NPEt₃)]₂ ( 2 ) and [GaI₂(NPPh₃)]₂ ( 3 ), on the other hand, are obtained by redox reactions as pale yellow crystals; ( 2 ) of “gallium(I) iodide” with Me₃SiNPEt₃ in toluene and ( 3 ) of gallium with N-iodine triphenylphosphaneimine, INPPh₃, in tetrahydrofuran. 1 and 3 are characterized spectroscopically and by crystal structure determinations; 2 is characterized only crystallographically. 1 : Space group Pbca, Z = 4; lattice dimensions at –70 °C: a = 1232.6(2), b = 1341.1(2), c = 1393.4(3) pm, R₁ = 0.0315. 1 forms centrosymmetric molecules in which the Al atoms are linked via Al–N bonds of the two (NPEt₃^–) groups; with 185.0 and 184.4 pm these bonds are of almost the same lengths. 2 : Space group Pbca, Z = 4; lattice dimensions at –80 °C: a = 1380.0(1), b = 1311.0(1), c = 1429.1(1) pm, R₁ = 0.0273. 2 crystallizes isotypically with 1 . The gallium atoms of the centrosymmetric Ga₂N₂ four-membered ring are connected with Ga–N distances of equal length (190.9 pm). 3 · THF: Space group P2₁2₁2₁, Z = 2; lattice dimensions at –140 °C: a = 1494.6(1), b = 1536.3(1), c = 974.6(1) pm, R₁ = 0.0382. 3 forms dimeric molecules in which the gallium atoms are linked via the N atoms of the (NPPh₃^–) groups to form a non-planar Ga₂N₂ four-membered ring of C₂ symmetry with Ga–N bonds of equal lengths – within standard deviations – of 194.7 pm. The phosphoraneiminato groups are arranged in a synperiplanar way.     

Vitamin K1 distribution following intravenous vitamin K1–fat emulsion administration in rats

This study investigated vitamin K₁ (VK₁) distribution following intravenous vitamin K₁–fat emulsion (VK₁–FE) administration and compared it with that after VK₁ injection. Rats were intravenously injected with VK₁–FE or VK₁. The organ and tissue VK₁ concentrations were determined using high‐performance liquid chromatography method at 0.5, 2 and 4 h to determine distribution, equilibrium and elimination phases, respectively. In the VK₁–FE group, the plasma, heart and spleen VK₁ concentrations decreased over time. However, other organs like liver, lung, kidney, muscle and testis, reached peak VK₁ concentrations at 2 h. In the VK₁ injection group, the liver VK₁ concentrations were significantly higher than those in other organs at the three time points. However, VK₁ concentrations in the other organs peaked at 2 h. In addition, in VK₁–FE group, the heart, spleen and lung VK₁ concentrations were significantly higher than those in the VK₁ injection group at the three time points, and the liver VK₁ concentration was significantly higher than that in the VK₁ injection group at 4 h. The VK₁ amount was greatest in the liver compared with the other organs. Thus, the liver is the primary organ for VK₁ distribution. The distribution of VK₁ is more rapid when injected as VK₁–FE than as VK₁. Copyright © 2015 John Wiley & Sons, Ltd.     

Li4Mn5O12包覆对三元正极材料结构和性能的影响

LiNi(1/3)Mn(1/3)Co(1/3)O2具有很高的理论比容量,但是三元正极材料在高电压下长循环时,其表面结构发生较大的衰退,导致电池的循环性能和倍率性能变差。本文采用耐高电压且结构稳定的富锂尖晶石Li4Mn5O(12)包覆LiNi(1/3)Mn(1/3)Co(1/3)O2可以有效改善材料的电化学性能。通过XRD、SEM、XPS和TEM等手段对包覆后的材料进行分析,证实了在LiNi(1/3)Mn(1/3)Co(1/3)O2的表面形成了10nm厚的均匀Li4Mn5O(12)的包覆层;在循环100圈后,包覆后的LiNi(1/3)Mn(1/3)Co(1/3)O2仍具有179.5m Ah/g的放电比容量和88.6%容量保持率,明显高于未包覆的LiNi(1/3)Mn(1/3)Co(1/3)O2的78.3%容量保持率。因此,利用富锂尖晶石Li4Mn5O(12)包覆LiNi(1/3)Mn(1/3)Co(1/3)O2为实现更高能量密度的锂离子电池提供了新的途径。     

Synthesis,Characterization, and Structures of Palladium(II) and Platinum(II) Complexes Containing N,N‐Bis(diphenylphos­phanyl)Naphthylamine

The reaction of 1‐naphthylamine with two equivalents of chlorodiphenylphosphine in the presence of triethylamine gave the ligand C₁₀H₇‐1‐N(PPh₂)₂ ( 1 ). Reaction of 1 with PdCl₂(CH₃CN)₂ or PtCl₂(cod) (1:1 molar ratio) afforded the complexes cis‐[PdCl₂{C₁₀H₇‐1‐N(PPh₂)₂}] ( 2 ) and cis‐[PtCl₂{C₁₀H₇‐1‐N(PPh₂)₂}] ( 3 ), respectively. Compounds 1 – 3 were identified and characterized by multinuclear NMR (¹H, ¹³C, ³¹P NMR) and IR spectroscopy. Crystal structure determinations of complexes 2 and 3 were carried out.     

Mcore-Ptshell(M=Fe、Co、Ni)纳米粒子电催化氧还原的对比研究

纳米Pt具有较高的氧还原催化活性,但抗甲醇性不足,对直接甲醇燃料电池的性能产生影响。本文采用胶体模板法制备Mcore-Ptshell(M=Fe、Co、Ni)核壳型纳米粒子,用XRD和TEM表征纳米粒子的微观形貌和结构,动电位法和交流阻抗考察电催化活性和抗甲醇性。结果显示,Mcore-Ptshell纳米粒子的平均粒径约为10 nm,壳层厚度约为2~3 nm,3种催化材料的氧还原活性均高于碳载纳米Pt,抗甲醇性也有明显提高,其中Fecore,1-Ptshell,1/C的活性最高,峰电流密度达到0.5833 mA.cm-2,Cocore,1-Ptshell,1/C次之,Nicore,1-Ptshell,1/C最低;Fecore,1-Ptshell,1/C与Nicore,1-Ptshell,1/C的抗甲醇性相当,略好于Cocore,1-Ptshell,1/C。     

Synthese und Struktur von (PPh4)3[Re2NCl10]

Synthesis and Crystal Structure of (PPh₄)₃[Re₂NCl₁₀] The rhenium(V) nitrido complex (PPh₄)₃[Re₂NCl₁₀] ( 1 ) is obtained from the reaction of (PPh₄)[ReNCl₄] with 1, 3‐dioxan‐(2‐ylmethyl)diphenyl phosphine in CH₂Cl₂/CH₃CN in form of orange red crystals with the composition 1 ·2CH₂Cl₂ crystallizing in the triclinic space group P1¯ with a = 1210.7(2), b = 1232.5(1), c = 2756.3(5) pm, α = 99.68(1)°, β = 100.24(1)°, γ = 98.59(1)° and Z = 2. The crystal structure contains two symmetry independent, centrosymmetrical complex anions [Re₂NCl₁₀]^3‐ with a symmetrical nitrido bridge Re=N=Re and distances Re(1) ‐ N(1) = 181.34(5) and Re(2) ‐ N(2) = 181.51(4) pm.     

The electronic structure of molecules by a many-body approach: V. Ionization potentials and one-electron properties of cyclopentadiene and 1-sila-cyclopentadiene-(2,4)

The valence ionization potentials (IP's) of cyclopentadiene and 1-sila-cyclopentadiene-(2,4) are studied by an ab initio many-body approach which includes the effect of electron correlation and reorganization beyond the Hartree-Fock approximation. The Hartree-Fock approximation gives the correct ordering of the IP's for cyclopentadiene but this ordering does not agree with the results of the previous experimental and theoretical studies. The ordering is 1a₂(π), 2b₁(π), 4b₂, 6a₁, 5a₁, 3b₂, 1b₁ (π), 4a₁, 2b₂, 3a₁. For sila-cyclopentadiene the ordering of the IP's is: 1a₂(π), 4b₂, 2b₁(π), 6a₁, 1b₁(π), 5a₁, 3b₂, 4a₁, 3a₁, 2b₂. The Hartree-Fock approximation is found to be incorrect with respect to the ordering of the 4b₂ and 2b₁(π) IP's. A number of one-electron properties are calculated in the one-particle approximation and compared with the available experimental data.     

Synthese und Koordinationsverhalten von (Ph3SnO)3As. Die Kristallstrukturen von (Ph3SnO)3As und [{(Ph3SnO)3As}Fe(CO)4]

Synthesis and Coordination Behaviour of (Ph₃SnO)₃As. The Crystal Structures of (Ph₃SnO)₃As and [{(Ph₃SnO)₃As}Fe(CO)₄] (Ph₃SnO)₃As ( 1 ) was obtained from the reaction of Ph₃SnOH with As₂O₃ in a dichloromethane/water mixture as solvent. Upon recrystallization from DMF 1 forms orthorhombic crystals, space group P2₁2₁2₁, with a = 977.3(2), b = 1903.5(3) and c = 2600.9(5) pm (at 220 K). In 1 the As atom is bound to three OSnPh₃ groups with As–O distances of 171.9(3)–174.9(3) pm. Reaction of 1 with Fe₂(CO)₉ gives [{(Ph₃SnO)₃As}Fe(CO)₄] ( 2 ). 2 crystallizes monoclinic, space group P2₁/n with a = 2242.3(5), b = 1112.6(2), c = 2353.0(5) pm and β = 111,46(2)° (at 220 K). In 2 the iron atom exhibits a trigonal bipyramidal coordination with the (Ph₃SnO)₃As ligand in an axial position. The Fe–As bond length is 230.5(1) pm.     

Thermodynamics of metal-ligand bond formation: XVI. Base adducts of some organotin compounds

Thermodynamic data have been obtained by calorimetric titration in benzene solution at 30° for reaction of organotin compounds with Lewis bases; data are reported for forty acid/base systems.Ph₃SnCl forms $\text{1}\text{1}$ adducts of low stability with pyridine (py) or 4-methyl-pyridine (4-mepy). Ph₂SnCl₂, Me₂SnCl₂, Bu₂SnCl₂ and Bu₂Sn(NCS)₂ form simultaneously $\text{1}\text{1}$ and $\text{1}\text{2}$ adducts with py or 4-mepy and $\text{1}\text{1}$ adducts with 2,2′-bipyridine or 1,10-phenanthroline (phen); the enthalpies of formation of the phen adducts are similar to those of $\text{1}\text{2}$ adducts with 4-mepy. With BuSnCl₃ and PhSnCl₃ it was not possible to obtain data for each step in addition of pyridine or 4-mepy. Adduct stabilities increase with increasing chloride substitution and in the order Bu < Me < Ph; adducts of Bu₂Sn(NCS)₂ are more stable than those of Bu₂SnCl₂.Tributylphosphine does not react with Ph₃SnCl but gives $\text{1}\text{1}$ adducts with the other tin compounds; only PhSnCl₃ adds a second molecule of this base. The $\text{1}\text{1}$ adducts are more stable than those with heterocyclic bases. Tributylamine brings about disproportionation of the compounds R₂SnX₂ to R₄Sn and SnX₄NBu₃.     

Aggregate morphology and flow behaviour of micellar alkylglycoside solutions

Solutions of n-nonyl-β-D-glucoside (C₉G₁), n-decyl-β-D-glucoside (C₁₀G₁), n-dodecyl-β-D-maltoside (C₁₂G₂), n-tetradecyl-β-D-maltoside (C₁₄G₂) and C₉G₁/C₁₀G₁ mixtures have been characterised by capillary viscometry and rheology in H₂O and D₂O, in order to map the influence of surfactant characteristics on micellisation over a wide concentration range. For the maltosides, the micellar solutions are shear thinning with a zero-shear viscosity that scales with concentration according to a power law with an exponent of about 5.8. In contrast, solutions of the glucosides C₉G₁, C₁₀G₁ and their mixtures show Newtonian flow behaviour and a much lower scaling exponent (<2.4). In C₉G₁/C₁₀G₁ mixtures, the scaling exponent decreases monotonously with increasing C₁₀G₁ content. The flow behaviour correlates with the packing requirements of the various surfactants, and are compatible with the idea that the maltosides form worm-like micelles, whereas the glucosides form branched, interconnected micelles (C₉G₁) and space-filling micellar networks (C₁₀G₁).     

Flame Spray Pyrolysis for Finding Multicomponent Nanomaterials with Superior Electrochemical Properties in the CoOx‐FeOx System for Use in Lithium‐Ion Batteries

High‐temperature flame spray pyrolysis is employed for finding highly efficient nanomaterials for use in lithium‐ion batteries. CoO_x‐FeO_x nanopowders with various compositions are prepared by one‐pot high‐temperature flame spray pyrolysis. The Co and Fe components are uniformly distributed over the CoO_x‐FeO_x composite powders, irrespective of the Co/Fe mole ratio. The Co‐rich CoO_x‐FeO_x composite powders with Co/Fe mole ratios of 3:1 and 2:1 have mixed crystal structures with CoFe₂O₄ and Co₃O₄ phases. However, Co‐substituted magnetite composite powders prepared from spray solutions with Co and Fe components in mole ratios of 1:3, 1:2, and 1:1 have a single phase. Multicomponent CoO_x‐FeO_x powders with a Co/Fe mole ratio of 2:1 and a mixed crystal structure with Co₃O₄ and CoFe₂O₄ phases show high initial capacities and good cycling performance. The stable reversible discharge capacities of the composite powders with a Co/Fe mole ratio of 2:1 decrease from 1165 to 820 mA h g^?1 as the current density is increased from 500 to 5000 mA g^?1; however, the discharge capacity again increases to 1310 mA h g^?1 as the current density is restored to 500 mA g^?1.     

E4 Butterfly Complexes (E=P,As) as Chelating Ligands

The coordination properties of new types of bidentate phosphane and arsane ligands with a narrow bite angle are reported. The reactions of [{Cp′′′Fe(CO)₂}₂(μ,η^1:1‐P₄)] ( 1 a ) with the copper salt [Cu(CH₃CN)₄][BF₄] leads, depending on the stoichiometry, to the formation of the spiro compound [{{Cp′′′Fe(CO)₂}₂(μ₃,η^1:1:1:1‐P₄)}₂Cu]⁺[BF₄]^? ( 2 ) or the monoadduct [{Cp′′′Fe(CO)₂}₂(μ₃,η^1:1:2‐P₄){Cu(MeCN)}]⁺[BF₄]^? ( 3 ). Similarly, the arsane ligand [{Cp′′′Fe(CO)₂}₂(μ,η^1:1‐As₄)] ( 1 b ) reacts with [Cu(CH₃CN)₄][BF₄] to give [{{Cp′′′Fe(CO)₂}₂(μ₃,η^1:1:1:1‐As₄)}₂Cu]⁺[BF₄]^? ( 5 ). Protonation of 1 a occurs at the “wing tip” phosphorus atoms, which is in line with the results of DFT calculations. The compounds are characterized by spectroscopic methods (heteronuclear NMR spectroscopy and IR spectrometry) and by single‐crystal X‐ray diffraction studies.     

Derivatives of M(η5-C5H5)2 (M = Mo,W) with alkenylpyridines and related ligands

Reactions of ligands 2-vinylpyridine 1, 4-vinylpyridine 2, 2-allylpyridine 3, 1-allylpyrazole 4, acrylonitrile 5 and allylcyanide 6 with the metallocene derivatives [Mo(η⁵-C₅H₅)₂H₃][PF₆] 7, [Mo(η⁵-C₅H₅)₂HI] 8, [W(η⁵-C₅H₅)₂H₃] [PF₆] 9, [Mo(η⁵-C₅H₅)₂H₂] 10, [M(η⁵-C₅H₅)₂Br₂], M = Mo 11, M = W 12 are described. Reaction of 7 with 1, 8 with 1, 3 with 8 and 4 with 8 gave mixtures of metallocyle isomers resulting from coordination of the nitrogen atom to molybdenum followed by internal hydrometallation; reaction of 11 with 1 gave an olefinic π complex; reaction of either 9 or 11 with 1 gave intractable oils; reactions of 8 with 2, 11 with 5, 12 with 5, 11 with 6 and 12 with 6 yielded monosubstituted products in which the ligand is N-coordinated.     

Single-Atom or Dual-Atom in TiO2 Nanosheet: Which is the Better Choice for Electrocatalytic Urea Synthesis?

As rising star materials, single-atom and dual-atom catalysts have been widely reported in the electro-catalysis area. To answer the key question: single-atom and dual-atom catalysts, which is better for electrocatalytic urea synthesis? we design two types of catalysts via a vacancy-anchorage strategy: single-atom Pd₁−TiO₂ and dual-atom Pd₁Cu₁−TiO₂ nanosheets. An ultrahigh urea activity of 166.67 mol_urea mol_Pd⁻¹ h¹ with the corresponding 22.54 % Faradaic efficiency at −0.5 V vs. reversible hydrogen electrode (RHE) is achieved over Pd₁Cu₁−TiO₂, which is much higher than that of Pd₁−TiO₂. Various characterization including an in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and theoretical calculations demonstrate that dual-atom Pd₁Cu₁ site in Pd₁Cu₁−TiO₂ is more favorable for producing urea, which experiences a C−N coupling pathway with a lower energy barrier compared with Pd₁ in Pd₁−TiO₂.     

Bimetallic complexes with porphyrins containing a cyclometalated phenylpyridine group

Treatment of Ni(HP¹) (H₃P¹ = meso-5-[4′-(2″-pyridyl)phenyl]-10,15,20-triphenyporphyrin) with K₂[PdCl₄] in EtOH afforded [Pd{Ni(P¹)}]₂(μ-Cl)₂ that reacted with NaS₂CNEt₂ to give Pd(S₂CNEt₂)[Ni(P¹)]. Reaction of Ni(HP¹) with [Ir(H)₂(PPh₃)₂(Me₂CO)₂][BF₄] afforded Ir(H)Cl(PPh₃)₂[Ni(P¹)]. The crystal structures of Pd(S₂CNEt₂)[Ni(P¹)] and Ir(H)(Cl)(PPh₃)₂[Ni(P¹)] have been determined.     

Phosphanimin‐Komplexe des Berylliums und Phosphaniminato‐Komplexe mit Heterokubanstruktur

Phosphaneimine Complexes of Beryllium and Phosphoraneiminato Complexes with Heterocubane Structure Beryllium dichloride reacts with the silylated phosphaneimine Me₃SiNPEt₃ in dichloromethane solution to give the monomeric donor‐acceptor complex [BeCl₂(Me₃SiNPEt₃)] ( 1 ). Under cleavage of trimethylchlorosilane the thermolysis of 1 at 160 °C leads to the formation of the phosphoraneiminato complex [BeCl(μ₃‐NPEt₃)]₄ ( 2 ) with heterocubane structure. In the presence of BeCl₂ 1 reacts in the melt to give the phosphoraneiminato complex [Be₄Cl₄(μ₃‐Cl)(μ₃‐NPEt₃)₃] ( 3 ), the structure of which corresponds with the structure of 2 by substitution of a ligand (μ₃‐NPEt₃)^— by a μ₃‐chloro ligand. As a by‐product from the synthesis of 2 in dichloromethane solution the phosphaneimine complex [BeCl₂(μ‐HNPEt₃)]₂·CH₂Cl₂ ( 4 ·CH₂Cl₂) can be obtained. Its dimeric units form dimers [{BeCl₂(μ‐HNPEt₃)}₂]₂ with symmetry D₂ via Cl···H‐N hydrogen bridges. The compounds 1 — 4 ·CH₂Cl₂ are characterized by X‐ray structure determinations, 1 — 3 additionally by IR spectroscopy. 1 : Space group C2/c, Z = 8, lattice dimensions at 193 K: a = 1502.5(1), b = 801.8(1), c = 2609.6(2) pm, β = 96.15(1)°, R₁ = 0.0523. 2 : Space group C2/c, Z = 4, lattice dimensions at 193 K: a = 1992.2(2), b = 1054.8(1), c = 1950.6(2) pm, β = 114.82(1)°, R₁ = 0.0275. 3 : Space group P2₁2₁2₁, Z = 4, lattice dimensions at 193 K: a = 1159.5(1), b = 1199.0(1), c = 2251.1(2) pm, R₁ = 0.0399. 4 ·CH₂Cl₂: Space group Ccca, Z = 8, lattice dimensions at 193 K: a = 1454.6(1), b = 2795.7(3), c = 1235.6(1) pm, R₁ = 0.0349.