TcCl4(H2O)2] and [Cl3(H2O)2TcOTc(H2O)2Cl3]--two molecular intermediates of the hydrolysis of technetium(IV)

Two molecular intermediates of the hydrolysis of technetium tetrachloride, cis-[TcCl4(H2O)2] and [Cl3(H2O)2TcOTc(H2O)2Cl3], were isolated and structurally characterised, suggesting that the hydrolytic degradation of technetium(IV) compounds occurs stepwise with the polymeric 'TcO2...nH2O' as a less defined final product.     

Crystal Structure of [M(NH3)5Cl]2[IrCl6]Cl2 (M = Co, Rh, Ir) Binary Complex Salts

Binary complex salts of M(NH₃)₅Cl]₂[IrCl₆]Cl₂ composition, where M = Co(III), Rh(III), or Ir(III), have been studied. All phases are isostructural with [M(NH₃)₅Cl]₂[PtCl₆]Cl₂ complexes [M = Rh(III) and Ir(III)]; Xray structural and crystallochemical analysis have been performed.     

[iPr2P]2P?SiMe3 und [iPr2P]2PLi – Synthese und Reaktionen Struktur des [iPr2P]2P?P[PiPr2]2

[iPr₂P]₂P? SiMe₃ and [iPr₂P]₂PLi – Synthesis and Reactions Structure of [iPr₂P]₂P? P[PiPr₂]₂ [iPr₂P]₂P? SiMe₃ 1 and [iPr₂P]₂PLi 2 were prepared to investigate the influence of the bulky alkyl groups on formation and properties of the ylides R₂P? P?P(X)R₂ (R = iPr, tBu; X = Br, Me) in reactions of 1 with CBr₄ and of 2 with 1,2-dibromoethane or MeCl, resp. Compared to the iPr groups the tBu groups favour the formation of ylides. With CBr₄ 1 forms iPr₂P? P?P(Br)iPr₂ 5 just as a minor product which decomposes already below ?30°C. With 1,2-dibromoethane 2 yields only traces of 5 but [iPr₂P]P? P[P(iPr)₂]₂ 7 as main product. With MeCl 2 gives iPrP? P?P(Me)iPr₂ 9 and [iPr₂P]₂PMe 10 in a molar ratio of 1:1. 9 is considerably more stable than 5. 7 crystallizes triclinic in the space group P1 (No. 2) with a = 10.813 Å, b = 11.967 Å, c = 15.362 Å, α = 67.90°, β = 71.36°, γ = 64.11° and two formula units in the unit cell.     

Synthesis,Spectroscopic Characterization and X-Ray Crystal Structure of the Chloride-Bridged Face-Sharing Bioctahedral Diiridium Complex [HP-t-Bu2Me][Ir2Cl7(P-t-Bu2Me)2], a Possible Precursor of the Complex [Ir(H)(Cl)2(P-t-Bu2Me)2]

Abstract

The reaction of an ethanolic suspension of [NH₄]₂[IrCl₆] and P-t-Bu₂Me, in the presence of HCl for 15h gives [HP-t-Bu₂Me][Ir₂Cl₇(P-t-Bu₂Me)₂], 1, in 13.5% yield. The dinuclear complex 1 was characterized by elemental analyses, IR, ¹H, ³¹P NMR spectroscopy, and single crystal X-ray analysis. However, when the above reaction is continued for 48 h one obtains only [Ir(H)(Cl)₂(P-t-Bu₂Me)₂], 2, in good yield. It is proposed that complex 1 is a reaction intermediate to 2. Crystallographic data for 1 (at 298 K): a = 16.151(3) Å, b = 11.885(2)Å, c = 21.665(4) Å, β = 90.26(2)°, space group P2_1/c (Z=4).     

Structural Characterization of trans-[Cr(NH3)4(H2O)Cl]Cl2 and trans-[Cr(NH3)4Cl2]l

Trans-[Cr(NH₃)₄(H₂O)Cl]Cl₂ (A) crystallizes in the monoclinic space group P2₁/m (No. 11) with a = 6.556(1), b = 10.630(5), c = 6.729(2) Å and β = 96.15(3)°. Trans-[Cr(NH₃)₄Cl₂]I (B) has monoclinic C2/m (No. 12) space group and a = 9.877(2), b = 8.497(2), c = 6.047(2) Å and β = 108.98(2)°. Both unit cells contain two formula units. Cr? Cl, Cr? O(H₂O) and three independent Cr? N(NH₃) distances for A are 2.98(1), 2.023(2), 2.067(2), 2.086(3) and 2.064(3) °. Cr? Cl and Cr? N(NH₃) bonds in B are 2.325(1) and 2.071(2) °. All octahedral angles are close to 90 and 180°. Both structures were refined to very low R values. Water molecule from trans-[Cr(NH₃)₄(H₂O)Cl]²⁺ is hydrogen bonded to both ionic chlorides. Cation and two anions form the motive which repeats itself in the crystal. Cations and anions of the second structure are distributed in layers. Each cation and anion have coordination number eight.     

Substitution inertness of [Ir(H2O)6]3+

Ligand substitution properties of the recently characterized pale-yellow [Ir(H₂O)₆]³⁺ ion in perchlorate solutions, have been investigated. At 120°C in sealed tubes observations on the exchange with H₂¹⁸O are impaired by a spurious oxidation to purple Ir(IV). Over extended periods at 40°C the ion has been shown to be extremely inert, and the rate constants for substitution of Cl⁻ into [Ir(H₂O)₆]³⁺ is estimated to be < 2 × 10⁻⁹ M⁻¹ S⁻¹.     

配合物[Co(benimtacn)Cl2]Cl·3H2O的合成、晶体结构及电化学性质

近年来,带悬臂的1,4,7-三氮环壬烷作为一类直接有效的配体引起了人们的兴趣[1,2],由于悬臂的柔顺性和多样性,这类配体可能形成非常有趣且稳定的配合物[3￣5]。特别是选择性悬臂配体形成的配合物,作为酶模型物时,容易形成催化活性空位[6￣8];悬臂较少,空间位阻较小的配体在形成配合物时易自组装成桥连双核二聚体[9,10]。     

Olefin Cycloadditions of the Electrophilic Phosphinidene Complex [iPr2N−P=Fe(CO)4]

Highly strained methylenephosphiranes are formed in the reaction of the new electrophilic phosphinidene complex [iPr₂N−P=Fe(CO)₄] with allenes. Remarkably, reaction with diallenes at 0°C also leads to a phosphirane, which rearranges upon warming to room temperature to a bis-isopropylidenephospholene (see scheme).     

Synthesis and Crystal Structure of Nitrosoruthenium Triammino Complex [RuNO(NH3)3Cl(H2O)]Cl2

This paper reports on a procedure for the synthesis of the compound [RuNO(NH₃)₃Cl(H₂O)]Cl₂. The complex was studied by IR spectroscopy and X-ray phase and X-ray diffraction analyses. Crystal data for RuCl₃N₄O₂H₁₁: a = 13.151(2), b = 6.852(1), c = 10.361(1) , V = 933.6(2) ², space group Pna2 ₁ , Z = 4, d _calc = 2.181 g/cm³, d _exp = 2.178 g/cm³. The structure consists of the [RuNO(NH₃)₃Cl(H₂O)]²⁺ complex cations and Cl^– anions. The compound crystallizes as small orange red isometric orthorhombic crystals well soluble in water and insoluble in concentrated hydrochloric acid and organic solvents and is stable when stored in air.     

Das iso-Tetraphosphan P[P(SiMe3)Me]2[P(SiMe3)2]

H ? C Bond Cleavage in Ferrocene by Organylruthenium Complexes Cp*(Me₃P)₂RuCH₂CMe₃ ( 1 ) reacts at 85°C with ferrocene ( 2 ) by cleavage of one H? C bond in 2 to give CpFe[η⁵-C₅H₄Ru(PMe₃)₂Cp*] ( 3 ) (Cp = η⁵-C₅H₅; Cp* = η⁵-C₅Me₅) and neopentane. The ruthenium atom in 3 has a distorted tetrahedral geometry, the planar Cp ligands in the ferrocenyl fragment are eclipsed. Solutions of 3 in [D₆]benzene or [D₈]THF exhibit H? D exchange of the ferrocenyl protons. In the [D₈]THF molecule only the α-deuterium atoms are exchanged. Reaction pathways for this exchange are discussed.