Über Umsetzungen von weißem Phosphor mit Metallorganylen

Reactions of White Phosphorus with Lithium Alkyls The reaction of white phosphorus with Lime (me = CH₃) (molar ratio P₄: Lime = 1:1) in DME or THF via insoluble lithium polyphosphides yields Li₃P₇ 1 , Li₂P₇me 2 and LiP₇me₂ 3 , which react with me₃SiCl or meBr to form P₇(Sime₃)₃, P₇(Sime₃)₂me and P₇me₃, respectively. All of these compounds were characterized by ³¹P-n.m.r. By higher amounts of Lime (molar ratio P₄:Lime = 1:2) Li₂P₇me is decomposed. The analogous reaction of P₄ with LiCme₃ yields Li₃P₇, LiP₇(Cme₃)₂, Li₂P₇Cme₃, and additionally LiP₄(Cme₃)₃ and LiP₃(Cme₃)₂. Again insoluble lithium polyphosphides were observed as intermediates. Addition of me₃SiCl to the reaction mixture affords P₇(Sime₃)₃, P₇(Sime₃)₂(Cme₃), P₇(Sime₃)(Cme₃)₂ P₄(Sime₃)(Cme₃)₃, and P₃(Sime₃)(Cme₃)₂. In n-hexane/THF the reaction of P₄ with LiCme₃ in the molar ratio of 1:2 predominantly yields the fourmembered ring LiP₄(Cme₃)₃ besides some of the three-membered ring LiP₃(Cme₃)₂, which with me₃SiCl yield P₄(Sime₃)(Cme₃)₃ and P₃(Sime₃)(Cme₃)₂. In addition to the mentioned main products are found: all compounds of the group P₈(Sime₃)₅(Cme₃) to P₈(Sime₃)(Cme₃)₅, the five-membered rings P₅(Sime₃)₂(Cme₃)₃ and P₅(Sime₃)₃(Cme₃)₂ as well as P(Sime₃)₂Cme₃ and P(Sime₃)₃.     

Untersuchungen zur Metallierung der Cyclophosphane P4(Cme3)3(Sime3), P4(Cme3)2(Sime3)2, P4(Sime3)4

Investigations Concerning the Metallation of the Cyclotetraphosphanes P₄(Cme₃)₃(Sime₃), P₄(Cme₃)₂(Sime₃)₂, and P₄(Sime₃)₄ The reaction of white phosphorus with LiCme₃ and me₃SiCl yields P₄(Sime₃)(Cme₃)₃ 1 . With n-buLi this crystalline cyclotetraphosphane forms the crystalline LiP₄(Cme₃)₃. In the same manner, n-buLi, with trans-P₄(Sime₃)₂(Cme₃)₂ 2 to yields LiP₄(Sime₃)(Cme₃)₂, which in contrast to LiP₄(Cme₃)₃ decomposes within a few hours yielding P(Sime₃)₂n-bu 6 , P(Sime₃)₃ 8 , LiP(Sime₃)₂ 9 and also the cyclic compounds P₄(Sime₃)(Cme₃)₃ 10 , LiP₄(Cme₃)₃ 11 and LiP₃(Cme₃)₂ 12 . The composition of the product mixture depends on the molar ratio of 2 to LiC₄H₉. At a molar ratio of 1:1 11 and 12 are not jet observed. At molar ratios of 1:1.5 and 1:2 P(Sime₃)₃ is not found. The amount of 11 and 12 grows with increasing concentration of n-buLi. On addition of n-buLi the solution of P₄(Sime₃)₄ immediately turns red. Li₃P₇ and Li₂P₇(Sime₃) (among others) are formed so fast that the first intermediates in the lithiation sequence so far could not be elucidated. These results demonstrate clearly that replacement of two me₃Si groups in P₄(Sime₃)₄ by two me₃C groups excludes the rearrangement of LiP₄(Sime₃)(Cme₃)₂ to a P₇-molecule.     

Das Hexamethyl-trisila-tetraphospha-nortricyclen,P4(Sime2)3

Hexamethyl-trisila-tetraphospha-nortricyclene, P₄ Sime₂₃ Reaction of white phosphorus with Na/K alloy and subsequent treatment with me₂SiCl₂ (me = CH₃) yields crystalline P₄(Sime₂)₃ (m. p. 159–160°C) along with polymeric silylphosphanes. The structure is derived from ³¹P-n.m.r.and mass spectra and turns out to be analogous to P₄S₃.     

Thermal decomposition of di-t-butyl peroxide in the presence of (CH3)2CCH2: Reactions of CH3, (CH3)2ĊCH2CH3, and (CH3)2ĊCH2C(CH3)2CH2CH3 radicals

A study of the reaction initiated by the thermal decomposition of di-t-butyl peroxide (DTBP) in the presence of (CH₃)₂C?CH₂ (B) at 391–444 K has yielded kinetic data on a number of reactions involving CH₃ (M·), (CH₃)₂CCH₂CH₃ (MB·) and (CH₃)₂?CH₂C(CH₃)₂CH₂CH₃ (MBB·) radicals. The cross-combination ratio for M· and MB· radicals, rate constants for the addition to B of M· and MB· radicals relative to those for their recombination reactions, and rate constants for the decomposition of DTBP, have been determined. The values are, respectively, where θ = RT ln 10 and the units are dm^3/2 mol^?1/2 s^?1/2 for k₂/k and k₉/k, s^?1 for k₀, and kJ mol^?1 for E. Various disproportionation-combination ratios involving M·, MB·, and MBB· radicals have been evaluated. The values obtained are: Δ₁(M·, MB·) = 0.79 ± 0.35, Δ₁(MB·, MB·) = 3.0 ± 1.0, Δ₁(MBB·, MB·) = 0.7 ± 0.4, Δ₁(M·, MBB·) = 4.1 ± 1.0, Δ₁(MB·, MBB·) = 6.2 ± 1.4, and Δ₁(MBB·, MBB·) = 3.9 ± 2.3, where Δ₁ refers to H-abstraction from the CH₃ group adjacent to the center of the second radical, yielding a 1-olefin. © 1994 John Wiley & Sons, Inc.     

Syntheses,Structures and Spectroscopic Studies of Quadruply Bonded Complexes Containing Bridging Acetate and η3-etp Ligands (etp = Ph2PCH2CH2P(Ph)CH2CH2PPh2)

The quadruply bonded complexes containing bridging acetate and polydentate phosphine ligands of the type Mo₂(O₂CCR₃)X_J(η³-etp) (R = H, X = Br, 1; R = F, X = CI, 2; R = F, X = Br, 3; etp = Ph₂PCH₂CH₂P(Ph)CH₂CH₂PPh₂) were prepared by reactions of Mo₂(O₂CCR₃)X₂(PPh₃)₂ with etp in CH₂X₂. Their UV-vis and ³¹P{¹H}-NMR spectra have been recorded, and the structure of 1 has been determined by X-ray crystallography. Crystal data for 1·2CH₂Br₂: space group P2₁/c, a = 13.924(7) Å, b = 21.157(4) Å, c = 14.427(5) Å, β = 101.82(3)°, V = 4159(2) ų, Z = 4, with final residuals R = 0.0797 and Rw = 0.0793. The absorption wavelengths of the δ → δ* transitions and the chemical shifts and the coupling constants of the ³¹P{¹H}-NMR spectra of these complexes are dependent on the natures of the halogen atoms and the acetate ligands.     

Bildung und Reaktionen P-funktioneller Phosphane

Formation and Reaction of P-functional Phosphanes The reaction of (me₃Si)₂PLi · 2 THF a (me = CH₃) with PCl₃ b at ?78°C via the intermediate (me₃Si)₂P? PCl₂ 1 yields [(me₃Si)₂P]₂PCl 2 and [(me₃Si)₂P]₂P? P(Sime₃)₂ 3 . By addition of me₃CLi c to the reaction mixture of a and b (molar ratio a:b:c (molar ratio a:b:c = 1:1:1) at ?60°C, 2 is formed as a main product, which reacts on to yield [(me₃Si)₂P]₂PH 4 (white crystals, mp = 73°C). By reactions of a:b:c in a molar ratio of 1:1:2 the cyclotetraphosphane (me₃C)₃ (me₃Si)P₄ 7 is accessible, and the additional formation of (me₃Si)₂PLi · 2 THF, (me₃Si)₃P and Li₃P₇ · 3 THF 13 was detected. Warming (me₃Si)₂P? PCl(Cme₃) 5 to 20°C produces cis- and trans-cyclotetraphosphanes (me₃Si)₂(me₃C)₂P₄. By running the reaction of a and b at ?78°C and adding me₃CLi only after 24 h, additionally to (me₃Si)₂P? PH Cme₃) and (me₃Si)₃P also (me₃Si)₂P? P(Cme₃)? P(Cme₃)? P (Sime₃)₂ is obtained, which is formed by metallation of (me₃Si)₂P? PCl(Cme₃) with me₃CLi and by further reaction of the intermediate (me₃Si)₂P? PLi(Cme₃) with (me₃Si)₂P? PCl(Cme₃). The reaction of (me₃Si₃)P with PCl₃ at ?78°C only yields (me₃Si)₂P? PCl₂ 1 and me₃SiCl. On addition of me₃CLi (?78°C, molar ratio = 1:1:1) preferrably 2 and (me₃Si)₂P? PCl(Cme₃) are formed, whereas after warming the mixture to 20°C, 4 and (me₃Si)₂P? PH(Cme₃) are found to be the main products. These reactions are induced by the cleavage of 1 by means of me₃CLi, and by the formation of (me₃Si)₂PLi and me₃C? PCl₂.     

Die Phosphide LiR2P7, Li2RP7 (R = Me3Si,Et, iPr,iBu) und alkyliert-silylierte Heptaphosphane(3)

The Phosphides LiR₂P₇, Li₂RP₇ (R = Me₃Si, Et, iPr, iBu) as well as Mixed Alkylated and Silylated Heptaphosphanes(3) Formation and properties of LiR₂P₇ and Li₂PR₇ (R = Me₃Si, Et, iPr, iBu) and their reactions with Me₃SiCl or alkylhalides yielding mixed alkylated and silylated heptaphosphanes(3) are reported. Reactions of (Me₃Si)₃P₇ and Li₃P₇. 3 DME produce mixtures of Li(Me₃Si)₃P₇, Li₂(Me₃Si)P₇ and Li₃P₇ from which pure Li(Me₃Si)₂P₇ (s, as) can be isolated by means of an extraction with toluene. Similarly, the isomers of LiR₂P₇ (R = Et, iPr, iBu) can be extracted from the mixtures obtained by reacting Li₃P₇ with alkylbromides. The (s) isomers of LiR₂P₇ in solution at about 20°C from the (as) isomers whereas the latter up to 70°C do not show any inversion. The (as) lithiumdialkylphosphides can be obtained as ether free products (red brown powder, isoluble in toluene, soluble in THF) by repeated addition of toluene and removal of the solvents; the (s) isomers decompose during the procure. In reactions of LiEt₂P₇. THF (s, as) in toluene at ?30°C with EtBr only the (s) isomer is substituted and gives Et₃P₇ (s), however on warming to 20°C by inversion of P^e a ratio of (s) : (as( = 1 : 3 is obtained. With Li(iBu)₂P₇, (s) reaction begins above ?20°C the giving both the (s) and the (as) isomer. (iBu)₃P₇ (s) is the prefered isomer at higher temperatures. Li(Me₃Si)₂P₇ (s, as) with Me₃SiCl exclusively yields (Me₃Si)₃P₇ (s). Li₂RP₇ (R = alkyl, Me₃SI) is not available. From mixtures with LiR₂P₇ and Li₃P₇, it can be isolated only after repeated cumbersome extraction of LiR₂P₇ as was shown with Li₂(iPr)P₇ as an example. Ether free LiEt₂P₇(s, as) with Me₃SiCl exclusively gives Et₂(Me₃Si)P₇ (s, as) whereas LiEt₂P₇ ? THF due to its THF content does not. Similarly, ether free Li(iBu)₂P₇ yields (iBu)₂(Me₃Si)P₇ (s, as). The compounds R(Me₃Si)₂P₇ (R = alkyl) cannot be selectively prepared neither starting from Li₂RP₇ with Me₃SiCI) nor from Li(Me₃Si)₂P₇ with RX. Such, the reaction of Li(Me₃Si)₂P₇ ? THF with EtBr in toluene at ?78°C yield a mixture of Et(Me₃Si)₂P₇ (42%), Et₂(Me₃Si)P₇ (27010), (Me₃Si)₃P₇ (29%) and Et₃P₇ (2%). (Me₃Si)₃P₇ with MeI in a molar ratio of 1 : 1 at 70°C quantitatively produces Me(Me₃Si)₂P₇ whereas already using a molar ratio of 1 : 2 also Me₃P₇ is obtained. With EtBr mixtures of Et(Me₃Si)₂P₇ and Et₃P₇ are formed. iBuBr gives iBu₃P₇, but tBuBr does not yield any tBu₃P₇.     

Beiträge zur Chemie des Phosphors. 100 [1]. Pentamethyl-heptaphosphan(5), P7(CH3)5, und Pentamethyl-nonaphosphan(5), P9(CH3)5

Contributions to the chemistry of phosphorus. 100. Pentamethyl-heptaphosphane(5), P₇(CH₃)₅, and pentamethyl-nonaphosphane(5), P₉(CH₃)₅ Two new methylphosphanes with condensed ring systems, P₇(CH₃)₅ ( 1 ) and P₉(CH₃)₅ ( 2 ), have been obtained by reacting mixtures of phosphorus(III) chloride with methyldichlorophosphane or pentamethylcyclopentaphosphane in presence of magnesium. Besides, the formation of P₇(CH₃)₃, P₈(CH₃)₆ and P₁₁(CH₃)₅ has been detected. 1 and 2 can be isolated in a pure state and have been characterized by elemental analysis, mass, IR, and NMR spectra as compounds with a norbornane-analogous P₇-skeleton and a noradamantane-analogous P₉-skeleton, respectively. Thereby, at the same time the structures of the hydrides P₇H₅ and P₉H₅ have unambiguously been clarified as bicyclo[2.2.1]heptaphosphane and tricyclo[3.3.1.0^3,7]nonaphosphane, respectively. 1 and 2 are formed as mixtures of various configurational isomers which differ in the arrangement of the methyl groups.     

Optically active transition-metal compounds: XXII. Stereochemistry and crystal structure determination of (η5-C5H5)CoI(NC4H3C(R)=N(S)-CH(CH3)(C6H5)) (R = H,CH3)

The crystal structures and absolute configurations of (η⁵-C₅H₅)-CoI(NC₄H₃-C(R)=N(S)-CH(CH₃)(C₆H₅)) (R = H, compound I; R = CH₃, compound II) have been determined by single crystal X-ray diffraction. Crystals of compound I are orthorhombic, with a 11.084(6), b 12.107(6) and c 13.121(7) Å, space group ^P2₁2₁2₁ and d (calcd, Z = 4) 1.69 g cm^?3 The structure was solved by the Patterson technique and refined with use of full matrix least-squares methods to R(F) = 0.031 and R_w(F) = 0.028. Compound II is nearly isomorphous and isostructural; a 11.246(6), b 11.923(6) and c 13.370(7) Å, d(calc., Z = 4) 1.71 g cm^?3 and was refined to the final agreement factors of R(F) = 0.044 and R_w(F) = 0.035. The Co atom has a distorted tetrahedral coordination, with Co-I 2.595(2) for I and 2.607(2) Å for II; Co-(η⁵-C₅H₅ ring centroid) 1.681(4) and 1.703(5) Å; Co-N(pyrrole) 1.905(9) and 1.885(9) Å; Co-N(imine) 1.971(8) and 2.003(9) Å, all the parameters being well within values found in the literature. The configuration around the chiral carbon of the phenylethylamine is S for both compounds, whereas the configuration around the metal is R in I and S in II. The different metal configurations in I and II have their origin in the two different substituents (R = H, CH₃) at the imine carbon atoms of the chelate ring, which induce completely different conformations of the (S)-CH(CH₃)(C₆H₅) moiety in the two complexes. For both compounds the thermodynamically less stable isomer is enriched upon crystallization. Also, for compound I the solution and solid state conformations are almost opposite to each other, the conformation in the solid reflecting intramolecular interactions (phenyl/C₅H₅ attraction).     

Transition-Metal-Substituted Gallanes: Synthesis and Spectroscopic Studies of Highly Polar σ(M—Ga) Bonds,Structures of trans-(Ph3P)(CO)3Co—Ga[(CH2)3N(C 2H5)2]R (R = Cl,CH3) and (n5-C5H5)(CO)2Fe—GaCl2 [N(CH3)3]

The salt elimination reaction of the transition carbonyl metal-lates [L(CO)_nM](Na/K) (M = Cr, Mo, W, Mn, Re, Fe, Co, Ni; L= CO, n⁵-C₅R₅, PR₃; n= 1-4; R= alkyl, aryl) with the base-stabilized galliumhalides Cl_aGaR₃ -a(Do) (R = H, alkyl, halide; Do = THF, N(CH₃)₃, NC₇H₁₃) or Cl_aGa[(CH₂)₃N-R₂](R)₂ - _a yielded almost quantitatively the transition metal-substituted, gallanes [L(CO)_nM]_aGaR₃ - _a(Do) and [L(CO)_n-M]_aGa[(CH₂)₃NR₂](R)₂ - _a, respectively. Residual halide functionalities in these complexes were selectively replaced by various other groups. The new compounds were characterized by means of elemental analysis, ¹H-, ¹³C-, ³¹P-NMR, MS, and lR v(CO) data. The single-crystal X-ray structure analysis of trans-(Ph₃P)(CO)₃Co-Ga[(CH₂) ₃N(C₂H₅)₂](R)( 6s : R = Cl, 6t : R= CH₃) showed s̀(Co-Ga) lengths of 237.78(4) and 249.5(1) pm, respectively. A short s̀(Fe-Ga) contact of 236.18(3) pm was found for (n⁵-C₅H₅)(CO)₂Fe-Ga-Cl₂[N(CH ₃)₃] ( 5a ). Low-pressure MOCVD experiments were performed to give thin films of analytically pure CoGa alloy.     

Untersuchungen zur Reaktionsfähigkeit der höheren Silylphosphane (me3Si)4P2, [(me3Si)2P]2PH, [(me3Si)2P]2P–Sime3 und (me3Si)3P7

Investigations Concerning the Reactivity of the Higher Silylphosphanes (me₃Si)₄P₂, [(me₃Si)₂P]₂PH, [(me₃Si)₂P]₂P—Sime₃, and (me₃Si)₃P₇ The reaction of (me₃Si)₂P? P(Sime₃)₂ 1 in ether solutions (THF, monoglyme) with t-buLi (me ? CH₃; t-bu ? (CH₃)₃C) yields (me₃Si)₃P, (me₃Si)₂PLi and Li₃P₇ via (me₃Si)₂P? P(Li) (Sime₃) 4 . Already at ?40° (me₃Si)₃P₂Li 4 decomposes yielding (me₃Si)₂PLi, Li₃P₇ and (me₃Si)₃P. The metallation of (me₃Si)₃P₂H with t-buLi leads to the same results. t-buLi with [(me₃Si)₂P]₂PH 2 in pentane forms [(me₃Si)₂P]₂PLi, which reacts on with meCl or me₃SiCl to [(me₃Si)₂P]₂Pme or [(me₃Si)₂P]₂PSime₃, resp. On addition of monoglyme to a suspension of [(me₃Si)₂P]₂PLi in pentane, or by treating [(me₃Si)₂P]₂PH in ethers with t-buLi (me₃Si)₂PLi, Li₃P₇, (me₃Si)₃P, are formed. The same compounds are generated by reacting [(me₃Si)₂P]₂P—Sime₃ in ethers with t-buLi. The metallation of (me₃Si)₃P₇ in ethers with t-buLi yields (me₃Si)₂PLi, (me₃Si)₃P, (t-bu)₃P₄?(Sime₃), Li₃P₇ and a red solid. The formation of (me₃Si)₂P₇Li is the first step of this reaction.     

Triethylphosphanimin-Komplexe der Acetate von Kupfer(II) und Zink. Kristallstrukturen von [Zn(O2C–CH3)2(HNPEt3)], [Cu5(O2C–CH3)10(HNPEt3)2] und [Cu(O2C–CH3)2(HNPEt3)2]

Triethylphosphanimine Complexes of the Acetates of Copper(II) and Zinc. Crystal Structures of [Zn(O₂C–CH₃)₂(HNPEt₃)], [Cu₅(O₂C–CH₃)₁₀(HNPEt₃)₂], and [Cu(O₂C–CH₃)₂(HNPEt₃)₂] The title compounds originate from the anhydrous acetates of zinc and copper(II) with trimethylsilyl-triethylphosphanimine, Me₃SiNPEt₃, in the presence of water in dichloromethane. They form colourless ( 1 ), bluish-green ( 2 ), and blue ( 3 ), respectively, single crystals, which were characterized by IR spectroscopy and by crystal structure analyses. [Zn(O₂C–CH₃)₂(HNPEt₃)] ( 1 ): Space group P 4 2₁c, Z = 8, lattice dimensions at –83 °C: a = b = 1709.6(2), c = 982.4(1) pm, R = 0.0551. 1 has a polymeric chain structure in which the zinc atoms are μ₂-bridged via the oxygen atoms of one of the two acetato groups, while the second acetato group and the phosphanimine are bonded terminally. [Cu₅(O₂C–CH₃)₁₀(HNPEt₃)₂]( 2 · 4 CH₂Cl₂): Space group P2₁/c, Z = 8, lattice dimensions at –80 °C: a = 1761.18(13), b = 4074.5(2), c = 1733.34(15) pm, β = 91.383(10)°, R = 0.0413. 2 consists of the two structural units [Cu₂(O₂C–CH₃)₄] and [Cu₃(O₂C–CH₃)₆(HNPEt₃)₂], which are connected via two of the acetato groups of the Cu₃-unit along the crystallographic a-axis to form three crystallographically independent polymeric strands. [Cu(O₂C–CH₃)₂(HNPEt₃)₂] ( 3 ): Space group P2₁/n, Z = 2, lattice dimensions at 20 °C: a = 695.49(8), b = 1217.85(10), c = 1380.05(7) pm, β = 96.451(7)°, R = 0.0291. 3 forms monomeric, centrosymmetric molecules with a square planar environment at the Cu atoms.     

Trans-methyl-azido-bis(triisopropylphosphin)platin(II), [PtN3(CH3)(PiPr3)2]

Trans-methyl-azido-bis(triisopropylphosphine)platinum(II), [PtN₃(CH₃)(PⁱPr₃)₂] [PtN₃(CH₃)(PⁱPr₃)₂] has been prepared by reductive elimination of ethane from [Pt(CH₃)₃N₃]₄ in the presence of triisopropylphosphine at 80 °C. The complex is characterized by IR and NMR spectroscopy and by crystal structure determination, as well as by ab initio calculations. [PtN₃(CH₃)(PⁱPr₃)₂], which is in trans-configuration here, crystallizes in the monoclinic space group P2₁, Z = 2, and with the lattice dimensions a = 806.9(1), b = 1384.3(1), c = 1093.8(1) pm, β = 94.107(10)°.     

Hg2(CH3SO3)2: Synthese,Kristallstruktur, thermisches Verhalten und Schwingungsspektroskopie

Hg₂(CH₃SO₃)₂: Synthesis, Crystal Structure, Thermal Behavior, and Vibrational Spectroscopy Colorless single crystals of Hg₂(CH₃SO₃)₂ are formed in the reaction of HgO, Hg, and HSO₃CH₃. In the monoclinic compound (I2/a, Z = 4, a=883.2(2), b=854.0(2), c=1188.9(2) pm, β = 92.55(2)°, R_all=0.0445) the Hg₂²⁺ ion is coordinated by two monodentate CH₃SO₃^— anions. Further contacts Hg‐O occur in the range from 262 to 276 pm and lead to a linkage of the [Hg₂(CH₃SO₃)₂] units. The thermal analysis shows that Hg₂(CH₃SO₃)₂ decomposes at 300° yielding elemental mercury. The mass numbers of the species evolved lead to the assumtion that SO₃, SO₂, CO₂, CO and H₂CO are formed during the reaction. In the IR and the Raman spectrum the typical vibrations of the CH₃SO₃^— ion are observed, the Raman spectrum shows the Hg‐Hg stretching vibration at 177 cm^—1 within the Hg₂²⁺ ion additionally.     

Dimolybdenum Complexes Containing Pairs of Bridging Diphosphine and Carboxylate Ligands. Synthesis and Structures of trans-Mo2(O2CCH3)2(μ-dppa)2(BF4)2 and trans-Mo2X2(O2C(CH2)nCH3)2(μ-dppa)2 (n = 2, 10 or 12; X = Cl or Br; dppa = N,N-Bis(diphenylphosphino)amine)

The red complex trans-Mo₂(O₂CCH₃)₂(μ-dppa)₂(BF₄)₂, 1 , was prepared by reaction of [Mo₂(O₂CCH₃)₂(CH₃CN)₆][BF₄]₂ with dppa (dppa = Ph₂PN(H)PPh₂) in THF. The reactions of Mo₂(O₂C(CH₂)_nCH₃)₄ with dppa and (CH₃)₃SiX (X = Cl or Br) afforded the complexes trans-Mo₂X₂(O₂C(CH₂)_nCH₃)₂(μ-dppa)₂ (X = Cl, n = 2, 2; X = Br, n = 2, 3; X = Cl, n = 10, 4 ; X = Cl, n = 12, 5 ). Their UV-vis, IR and ³¹P{¹H}-NMR spectra have been recorded and the structures of 1, 2 and 3 have been determined. Crystal data for 1 : space group P2₁/n, a = 12.243(1) Å, b = 17.222(1) Å, c = 13.266(1) Å, β = 95.529(1)°, V = 2784.1(6) ų, Z = 2, with final residuals R = 0.0509 and Rw = 0.0582. Crystal data for 24CH₃Cl₂: space group P2₁/n, a = 13.438(1) Å, b = 19.276(1) Å, c = 14.182(1) Å, β = 111.464(1)°, V = 3418.9(6) ų, Z = 2, with final residuals R = 0.0492 and Rw = 0.0695. Crystal data for 3·4CH₂Cl₂: space group P2₁/n, a= 13.579(1) Å, b = 19.425(1) Å, c = 14.199(1) Å, β = 111.881(2)°, V = 3475.6(7) ų, Z = 2, with final residuals R = 0.0703 and Rw = 0.0851. Comparison of the structural data shows that the effect of the axial ligand on weakening the Mo-Mo bond strength is X^? > CH₃CN > BF₄^?. The T_m values are 121.7 °C for 2 , 111.1 °C for 3 and 91.5 °C for 5 , respectively.     

Synthese und Kristallstruktur des heterobimetallischen Diorganozinndichlorids (FcN,N)2SnCl2 (FcN,N—: (η5‐C5H5)Fe{(η5‐C5H3[CH(CH3)N(CH3)CH2CH2NMe2]‐2}—)

Synthesis and Crystal Structure of the Heterobimetallic Diorganotindichloride (FcN, N)₂SnCl₂ (FcN, N^—: (η⁵‐C₅H₅)Fe{η⁵‐C₅H₃[CH(CH₃)N(CH₃)CH₂CH₂NMe₂]‐2}^—) The heterobimetallic title compound [(FcN, N)₂SnCl₂] ( 1 ) was obtained by the reaction of [LiFcN, N] with SnCl₄ in the molar ratio 1:1 in diethylether as a solvent. The two FcN, N^— ligands in 1 are bound to Sn through a C‐Sn σ‐bond; the amino N atoms of the side‐chain in FcN, N^— remain uncoordinated. The crystals contain monomeric molecules with a pseudo‐tetrahedral coordination at the Sn atom: Space group P2₁/c; Z = 4, lattice dimensions at —90 °C: a = 9.6425(2), b = 21.7974(6), c = 18.4365(4) Å, β = 100.809(2)°, R1_obs· = 0.051, wR2_obs· = 0.136.     

Synthese,Eigenschaften und Struktur von [Li(OC4H8)4][((CH3)3Si)3C–InBr3]

Synthesis, Properties, and X-Ray Structure Determination of [Li(OC₄H₈)₄][((CH₃)₃Si)₃C–InBr₃] The reaction of InBr₃ with LiR* · (THF)_n (R* = –C(SiMe₃)₃, THF = OC₄H₈) in a 1 : 1 molar ratio forms [Li(THF)₄][R*InBr₃] in good yield. The properties and some spectroscopic data (¹H, ¹³C, ²⁹Si, ⁷Li–NMR, IR and Raman) of this trisyl-tribromoindate are given and the crystal structure has been determined.     

Synthese und Strukturbestimmung von (tBuP)4Sn(CH3)2 und (CH3)2Sn[(tBu)P?P(tBu)]2Sn(CH3)2

Synthesis and Structure Analysis of (tBuP)₄Sn(CH₃)₂ and (CH₃)₂Sn[(tBu)P? P(tBu)]₂Sn(CH₃)₂ The diphosphides K₂[(tBu)P? (tBuP)₂? P(tBu)] 7 or K₂[(tBu)P? P(tBu)] 8 react with (CH₃)₂SnCl₂ in a molar ratio of 1 : 1 to form the binary 5-membered ring system P₄Sn 4 a and the 6-membered ring system Sn(P₂)₂Sn 5 a respectively. When (CH₃)₂SnCl₂, however, is treated with 8 in a molar ratio of 2 : 1 the 4-membered ring system P₃Sn 2 a is formed which includes the fragmentation of the intermediate K₂[(CH₃)₂Sn ((tBu)P? P(tBu))₂] 9. 4 a and 5 a could be obtained in a pure form and characterized NMR spectroscopically and by X-ray structure analyses; 2 a was identified only NMR spectroscopically.     

Kombination von Ionenaustausch und Gefriertrocknung als Syntheseweg zu neuen Oxoferraten(VI) M2FeO4 mit M = Li,Na, N(CH3)4, N(CH3)3Bzl,N(CH3)3Ph

Combination of Ion Exchange and Freeze Drying as a Synthetic Route to New Oxoferrates(VI) M₂FeO₄ with M = Li, Na, N(CH₃)₄, N(CH₃)₃Bzl, N(CH₃)₃Ph For the first time Oxoferrates(VI) M₂FeO₄ with M = Li, Na, N(CH₃)₄, N(CH₃)₃Bzl and N(CH₃)₃Ph have been prepared by cation exchange reaction on K₂FeO₄ and freeze drying of the resulting aqueous solutions. Li₂FeO₄ crystallizes as a monohydrate and decomposes at –10 ± 3 °C. Na₂FeO₄ crystallizes orthorhombically (Cmcm, a = 5.675(3) Å, b = 9.349(4) Å, c = 7.160(2) Å) and is isostructural to Na₂CrO₄. [N(CH₃)₄]₂FeO₄ crystallizes tetragonally (P4/nbm, a = 11.010(3) Å, c = 10.902(4) Å) and is isostructural to the room temperature modification of [N(CH₃)₄]₂SO₄. Infrared spectra of the alkylammonium ferrates(VI) show a decreasing influence of lattice forces on the vibrations of the FeO₄^2– ions with increasing cation size. Magnetic measurements show the expected paramagnetism for a d² ion.     

Lithiumhydridosilylamide R2(H)SiN(Li)R′ – Darstellung,Eigenschaften und Kristallstrukturen

Lithium Hydridosilylamides R₂(H)SiN(Li)R′ – Preparation, Properties, and Crystal Structures The hydridosilylamines R₂(H)SiNHR′ ( 1 a : R = CHMe₂, R′ = SiMe₃; 1 b : R = Ph, R′ = SiMe₃; 1 c : R = CMe₃, R′ = SiMe₃; 1 d : R = R′ = CMe₃) were prepared by coammonolysis of chlorosilanes R₂(H)SiCl with Me₃SiCl ( 1 a , 1 b ) as well as by reaction of (Me₃C)₂(H)SiNHLi with Me₃SiCl ( 1 c ) and Me₃CNHLi with (Me₃C)₂(H)SiCl ( 1 d ). Treatment of 1 a–1 d with n-butyllithium in equimolar ratio in n-hexane resulted in the corresponding lithiumhydridosilylamides R₂(H)SiN(Li)R′ 2 a–2 d , stable in boiling m-xylene. The amines and amides were characterized spectroscopically, and the crystal structures of 2 b–2 d were determined. The comparison of the Si–H stretching vibrations and ²⁹Si–¹H coupling constants indicates that the hydrogen atom of the Si–H group in the amides has a high hydride character. The amides are dimeric in the solid state, forming a planar four-membered Li₂N₂ ring. Strong (Si)H … Li interactions exist in 2 c and 2 d , may be considered as quasi tricyclic dimers. The ‘‘NSiHLi rings”︁”︁ are located on the same side of the central Li₂N₂ ring. In 2 b significant interactions occurs between one lithium atom and the phenyl substituents. Furthermore all three amides show CH₃ … Li contacts.