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.     

1-Ethoxycarbonyl-3-ferrocenyl-propan-1,3-dion und Ferrocen-1,1'bis(2,4-dioxobutansäureethylester) als Liganden für Übergangsmetallionen. Kristallstruktur von Bis(1-ethoxycarbonyl-3-ferrocenyl-propan-1,3dionato)kupfer(II)

1-Ethoxycarbonyl-3-ferrocenyl-propane-1,3-dion and Ferrocene-1,1′bis(2,4-dioxobutanoic acid ethylester) as Ligands for Transition Metal Ions. Crystal Structure of Bis(1-ethoxycarbonyl-3-ferrocenyl-propane-1,3dionato)copper(II) The ligands 1-ethoxycarbonyl-3-ferrocenyl-propane-1,3-dion and ferrocene-1,1′-bis(2,4-dioxo-butanoic acid ethylester) have been prepared by reaction of acetylferrocene or 1,1′-diacetylferrocene and diethyl oxalate. They yield neutral chelates with Cu^II, Ni^II, Zn^II, Co^II, and Mn^II. The acid dissociation constants of the ligands and the stability constants of their metal complexes including Fe^II complexes are reported. The structure of bis(1-ethoxycarbonyl-3-ferrocenyl-propane-1,3-dionato)copper(II) was determined by X-ray structure analysis. A cis arrangement with a nearly square planar coordination sphere at the Cu atom is found.     

Studies on crystal transition of polyamide 11 nanocomposites by variable-temperature X-ray diffraction

Polyamide I1 （PAll） and its nanocomposites with different organoclay loadings were prepared by melt-compounding and subsequent pelletizing. The crystal phase transitions of PAl 1 and its clay nanocomposites were investigated by variable-temperature X-ray diffraction. It was found that the Brill transition of the nanocomposite was 20 K higher than that of the neat PAl 1 for both heating and cooling processes. The PAl 1 d-spacings of the nanocomposites were observed to be smaller than those of the neat PAl 1 for melt crystallization. The constraints imposed by the addition of layered clay, restricting the thermal expansion of the polymer chains, are probably responsible for such a reduction of the d-spacing.     

痕量铁的光化学伏安分析法及其应用研究

在稀硫酸介质中及活化剂草酸存在下，痕量铁（Ⅲ）对结晶紫光化学褪色反应有强烈催化作用，结晶紫的光化学反应产物于－０．７０产生一灵敏的２．５次微分级谱波。     

Untersuchung der Phasenbeziehungen in quaternären Systemen Bi2O3/Bi2Ch/Bi2Ch (Ch = S,Se, Te)

Investigations of the Phase Relations in the Quaternary Systems Bi₂O₃/Bi₂Ch /Bi₂Ch (Ch = S, Se, Te) The stability ranges in the pseudobinary systems Bi₂O₂S/Bi₂O₂Se, Bi₂O₂S/Bi₂O₂Te and Bi₂O₂Se/Bi₂O₂Te have been studied by solid state and chemical transport reactions. A complete mixed crystal Bi₂O₂(Te_xSe_1–x), 0 ≤ x ≤ 1 exists between the ternary compounds Bi₂O₂Te and Bi₂O₂Se. The thermal behaviour of the mixed crystal and the coexistence ranges have been determined by x‐ray and thermal analysis.     

[{Cp*(OC)2Re}2(μ‐POH)], ein Zweikernkomplex mit einem verbrückenden Hydroxiphosphiniden‐Liganden

[{Cp*(OC)₂Re}₂(μ‐POH)], a Dinuclear Complex with a Bridging Hydroxiphosphinidene Ligand The reaction of [{Cp*(OC)₂Re}₄(μ₄‐η¹ : η¹ : η¹ : η¹‐P₂)] ( 1 ) with 0.1 m HCl gives [{Cp*(OC)₂Re}₂(μ‐POH)] ( 2 ), the X‐ray crystal structure of which reveals a dinuclear rhenium complex with a μ‐POH (hydroxiphosphinidene) ligand.     

Iodoplumbate mit vier‐ und fünffach koordinierten Pb2+‐Ionen

Iodoplumbates with Tetra‐ and Penta‐coordinated Pb²⁺ Ions In contrast to all known iodoplumbates with octahedrally coordinated Pb²⁺ ions, square pyramidal geometry is observed in the iodoplumbate chains of (Pr₄N)[PbI₃] ( 1 ) and [Mg(dmf)₆][PbI₃]₂ ( 2 ), whereas the isolated anions in (Ph₄P)₂[Pb₂I₆] ( 3 ) and [Bu₃N–(CH₂)₃–NBu₃][PbI₄] ( 4 ) contain tetra‐coordinated lead atoms. (Pr₄N)[PbI₃] ( 1 ): a = 910.86(6), b = 1221.46(7), c = 1907.7(1) pm, V = 2122.5(2) · 10⁶ pm³, space group P2₁2₁2₁; [Mg(dmf)₆][PbI₃]₂ ( 2 ): a = 891.24(9), b = 1025.34(7), c = 1234.82(9) pm, α = 92.938(8), β = 106.457(8), γ = 98.100(7)°, V = 1066.4(2) · 10⁶ pm³, space group P1; (Ph₄P)₂[Pb₂I₆] ( 3 ): a = 1174.5(1), b = 722.29(7), c = 3104.8(4) pm, β = 100.50(1)°, V = 2589.8(5) · 10⁶ pm³, space group P2₁/n; [Bu₃N–(CH₂)₃–NBu₃][PbI₄] ( 4 ): a = 2178.3(1), b = 1008.63(5), c = 1888.3(1) pm, β = 110.003(5)°, V = 3898.6(4) · 10⁶ pm³, space group P2/c.     

Synthese und Kristallstrukturen der Nitrido‐Chloro‐Molybdate [Mg(THF)4{NMoCl4(THF)}2] · 4 CH2Cl2 und [Li(12‐Krone‐4)(NMoCl4)]2 · 2 CH2Cl2

Syntheses and Crystal Structures of the Nitrido‐chloro‐molybdates [Mg(THF)₄{NMoCl₄(THF)}₂] · 4 CH₂Cl₂ and [Li(12‐Crown‐4)(NMoCl₄)]₂ · 2 CH₂Cl₂ Both the title compounds as well as [Li(12‐crown‐4)₂]⁺MoNCl₄^– were made from MoNCl₃ and the chlorides MgCl₂ and LiCl, respectively, in dichloromethane suspensions in the presence of tetrahydrofuran and 12‐crown‐4, respectively. They form orange‐red moisture‐sensitive crystals, which were characterized by their IR spectra and partly by crystal structure analyses. [Mg(THF)₄{NMoCl₄(THF)}₂] · 4 CH₂Cl₂ ( 1 ): space group C2/m, Z = 2, lattice dimensions at –50 °C: a = 1736.6(1), b = 1194.8(1), c = 1293.5(2) pm; β = 90.87(1)°; R₁ = 0.037. In 1 the magnesium ion is coordinated octahedrally by the oxygen atoms of the four THF molecules and in trans‐position by the nitrogen atoms of the two [N≡MoCl₄(THF)]^– ions. [Li(12‐crown‐4)(NMoCl₄)]₂ · 2 CH₂Cl₂ ( 2 ): space group P 1, Z = 1, lattice dimensions at –70 °C: a = 930.4(1), b = 957.9(1), c = 1264.6(1) pm; α = 68.91(1)°, β = 81.38(1)°, γ = 63.84(1)°; R₁ = 0.0643. 2 forms a centrosymmetric ion ensemble in the dimeric cation of which, i. e. [Li(12‐crown‐4)]₂²⁺, the lithium ions on the one hand are connected to the four oxygen atoms each of the crown ether molecules in a way not yet known; and in addition, each of the lithium ions enters into a intermolecular Li–O bond with neighboring crown ether molecules under formation of a Li₂O₂ four‐membered ring. The two N≡MoCl₄^– counterions are loosely coordinated to one oxygen atom each of the crown ether molecules with Mo–O distances of 320.2 pm.     

Phosphaniminato‐Cluster von Eisen. Die Kristallstrukturen von [FeCl(NPEt3)]4, [Fe(C=C–SiMe3)(NPEt3)]4 und [Fe3Cl4{NP(NMe2)3}3]

Phosphoraneiminato Cluster of Iron. The Crystal Structures of [FeCl(NPEt₃)]₄, [Fe(C=C–SiMe₃)(NPEt₃)]₄, and [Fe₃Cl₄{NP(NMe₂)₃}₃] The reaction of iron dichloride with the silylated phosphaneimine Me₃SiNPEt₃ in the presence of potassium fluoride at 165 ?C leads to the phosphoraneiminato complex [FeCl(NPEt₃)]₄ ( 1 ). Compound 1 forms black, moisture and oxygen sensitive crystals. According to the crystal structure analysis 1 has a heterocubane structure, in which the iron and the nitrogen atoms of the NPEt₃^– groups occupy the corners of a distorted cube and form Fe–N–Fe bond angles of 83.1? and N–Fe–N angles of 96.5?. This results in significantly short Fe…Fe contacts of 272.9 pm. The results of magnetic susceptibility measurements in the range of temperatures from 1.8 to 293 K and the ⁵⁷Fe‐Mössbauer spectra in the range of temperatures from 2 to 300 K are reported. Compound 1 reacts with the lithiated acetylenes LiC=C–CMe₃ and LiC=C–SiMe₃ in n‐hexane to form the iron‐organic derivatives [Fe(C=C–R)(NPEt₃)]₄ [R = CMe₃ ( 2 a ), R = SiMe₃ ( 2 b )] keeping the heterocubane structure. Compounds 2 a and 2 b form crystals which are very reactive and also black. According to the crystal structure analysis 2 b has a Fe₄N₄ heterocubane structure which is less distorted than that in 1 with bond angles Fe–N–Fe of 85.5? and N–Fe–N of 94.2?. This leads to the longer Fe…Fe contacts of 281.4 pm. With the dimethylamido derivative Me₃SiNP(NMe₂)₃ iron dichloride reacts under conditions similar to those in the synthesis of 1 to form the dark green mixed‐valenced Fe^II/Fe^III cluster [Fe₃Cl₄{NP(NMe₂)₃}₃] ( 3 ). According to the crystal structure analysis the three iron atoms in 3 are connected via one μ₃‐N atom of a NP(NMe₂)₃^– ligand, via two μ‐N atoms of the two remaining phosphoraneiminato ligands, and via one μ‐Cl atom to form an incomplete heterocubane skeleton.     

Synthesis,Structure, and Decomposition of (NH4)2[Mo6Cl14] · H2O

(NH₄)₂[Mo₆Cl₁₄] · H₂O ( 1 ) was prepared from reactions of MoCl₂ in ethanol with aqueous NH₄Cl solution. It crystallizes in the monoclinic space group I2/a (no. 15), Z = 4 with a = 912.3(1), b = 1491.2(2), c = 1724.8(2) pm, β = 92.25(1)°; R1 = 0.023 (based on F values) and wR2 = 0.059 (based on F² values), for all measured X‐ray reflections. The structure of the cluster anion can be given as [(Mo₆Cl)Cl]^2– (i = inner, a = outer ligands). Thermal stability studies show that 1 loses crystal water followed by the loss of NH₄Cl above 350 °C to yield MoCl₂. The water‐free compound (NH₄)₂[Mo₆Cl₁₄] ( 2 ) was synthesized by solid state reaction of MoCl₂ and NH₄Cl in a sealed quartz ampoule at 270 °C. No single‐crystals could be obtained. Decompositions of 1 and 2 under nitrogen and argon exhibited the loss of NH₄Cl at about 350 °C. Decomposition under NH₃ resulted in the formation of MoN and Mo₂N at 540 °C and 720 °C, respectively.