Aryl- und Arin-Komplexe von Übergangsmetallen der sechsten Gruppe Darstellung von [Mo(p-C6H4CH3)6(Li · OC4H10)3] und [W(p-C6H4CH3)4(C6H3CH3)2(Li · OC4H10)4] sowie NMR-spektroskopische Untersuchung des W-Komplexes

Aryl and Aryne Complexes of Group Six Transition Metals. Preparation of [Mo(p-C₆H₄CH₃)₆(Li · OC₄H₁₀)₃] und [W(p-C₆H₄CH₃)₄(C₆H₃CH₃)₂(Li · OC₄H₁₀)₄] and NMR Spectroscopic Investigation of the W Complex Molybdenum(V) chloride reacts with an etheral solution of p-tolyllithium (molar ratio 1:10) to yield a yellow, strongly paramagnetic hexatolylo complex ([MoTol₆(Li · S)₃]¹) (μ_eff = 3.51 B.M.), while from tungsten(V) bromide and p-tolyllithium (molar ratio 1:11) a blackish violet, diamagnetic complex [WTol₄Tn₂(Li · S)₄] is formed, containing two tolylene or tolyne groups for ligands. The ¹H-NMR spectrum points to the Tol-ligands being influenced by the methyl groups of the Tn-ligands.     

The σ2π4 Triple Bond between Molybdenum and Tungsten Atoms: Developing the Chemistry of an Inorganic Functional Group

Numerous analogies between organic and inorganic chemistry have emerged in recent years. The most prominent example is the isolobal relationship. Many reactions have shown that metal-metal double and triple bonds exhibit a pattern of reactivity similar to that of alkenes and alkynes. In compounds containing a σ²π⁴ triple bond between molybdenum and tungsten atoms, the M? M bond order can be increased from three to four by reductive elimination or decreased from three to two or one by oxidative addition. Complexes with M?M bonds can be used to prepare clusters or can serve as catalysts. In this review relationships between structure (electronic and stereochemical) and reactivity that are characteristic for modern inorganic chemistry are discussed.     

Crystal structure of [p-C6H4(CH2ImMe)2][PtCl6].

The structure of the title complex consists of a [p-C6H4(CH2ImMe)2]2+ and [PtCl6](2-) pair. The platinum atom is hexacoordinated by six chloride ions in octahedral coordination geometry. The average Pt-Cl bond distance is 2.3199 A. The imidazolium cation and hexachloroplatinate anion are linked via hydrogen bonds, and the crystal packing is governed by the CH...Cl interactions.     

Four‐ and Five‐Coordinate Gallium Complexes Stabilized by Bidentate 2‐(Dimethylaminomethyl)Pyrrole Ligand: Molecular Structures of Ga[NC4H3(CH2NMe2)‐2]3 and GaMe2[NC4H3(CH2NMe2)‐2]

Treatment of GaCl₃ with one equiv of Li[NC₄H₃(CH₂NMe₂)‐2] (n = 1, 2, 3) in diethyl ether at ?78 °C yields GaCl_3‐n[NC₄H₃(CH₂NMe₂)‐2]_n (n = 1, 1 ; n = 2, 2 ; n = 3, 3 ). Compound 1 reacts with two equiv of RLi to afford GaR₂[NC₄H₃(CH₂NMe₂)‐2] ( 4a, R=Me; 4b, R=Bu ) via transmetallation. Reacting 2 with one equiv of RLi in diethyl ether, 3 and 4 are formed via ligand redistribution. Variable temperature ¹H NMR spectroscopic experiments reveal that the five‐coordinate gallium compound 3 is fluxional and results in a coalescence temperature at 5 °C, at which ΔG^≠ is calculated at ca. 10.4 Kcal/mole. All the new compounds have been characterized by ¹H and ¹³C NMR spectroscopy and the structures of compounds 3 and 4a have also been determined by X‐ray crystallography.     

Darstellung und NMR-spektroskopische Untersuchung eines hexakoordinierten p-Tolylo-tantal(V)-Komplexes: [(p-CH3C6H4)5 Ta(p-CH3C6H4)Li · O(C2H5)2]

Preparation and N.M.R.-spectroscopie Investigation of a Hexacoordinated p-Tolylotantalum(V) Complex: [(p-CH₃C₆H₄)₅Ta(p-CH₃C₆H₄)Li · O(C₂H₅)₂] Reaction of tantalum(V) bromide with an etheral solution of p-tolyllithium in the molar ratio 1:5 leads to precipitation of a yellow complex of the brutto formula LiTaTol₆ · Ae[Tol = p-CH₃C₆H₄^?; Ae = (C₂H₅)₂O]. The ¹H and ¹³C n.m.r. spectra are discussed.     

Benzyl-tris(trimethylsilyl)methylzinndihalogenide, {(CH3)3Si}3C(C6H5–CH2)SnHal2 mit Hal = Cl,Br, I

Benzyl-tris(trimethylsilyl)methyl Tin Dihalides, {(CH₃)₃Si}₃C(C₆H₅–CH₂)SnHal₂ with Hal = Cl, Br, I The tin tetrahalides SnHal₄ (Hal = Cl, Br, I) react with base-free tris(trimethylsilyl)methyllithium (Tsi–Li) solved in toluene to form the trihalides Tsi–SnHal₃. But when the reaction is carried out in a 1 : 2 molar ratio at 60 °C in toluene, Tsi–H, Tsi–Hal and benzyl-trisyl tin-dihalides are formed in good yields, respectively. The nmr (¹H, ¹³C, ²⁹Si, ¹¹⁹Sn) and the Raman spectra are discussed, the X-ray structure analyses of the dibromide as well as the diiodide have been measured.     

Hydrothermal Synthesis and Crystal Structure of a New Phosphonate： {[Cu（1,10-phen）]2-（H2O3PCH2C6H4C6H4CH2PO3H）2-（HO3PCH2C6H4C6H4CH2PO3H） }n

1 INTRODUCTION Metal organophosphonates have attracted considerable attention for over three decades due to their potential or practical applications, include- ing ion exchanges[1, 2], molecular sensors[3] and optics[4, 5]. Recently, a number of porous m…     

Study of (π-C5H5)2Ti(CH3)Cl and (π-C5H5)2Ti(C6H5)Cl in soluble Ziegler catalysts

Soluble ethylene polymerization catalysts derived from (π-C₅H₅)₂Ti(R)Cl and R ′AlCl₂, where R = methyl or phenyl and R ′ = methyl or ethyl, were studied both by polymerization kinetics at 0°C and by diagnostic experiments. It was found that the first insertion of ethylene into the Ti? R bond is difficult when R = methyl or phenyl, and for this reason these catalysts show a different overall behavior than when R = ethyl or higher alkyl.     

(Carbonyl)Iron‐Selenolates: New Synthetic Methods and Reactions with Electrophiles. Crystal Structures of [(CO)6Fe2(μ‐SeR)2]; R = Me3SiCH2 and p‐O2NC6H4CH2, {(CO)6Fe2[μ‐η2‐Se,Se′‐o‐(SeCH2C6H4CH2Se)]}, and [(CO)6Fe2(μ‐SeFe(CO)2cp)2]

The reactions of Fe(CO)₅ or Fe₃(CO)₁₂ with NaBEt₃H or KB[CH(CH₃)C₂H₅]₃H, respectively and treatment of the resulting carbonylates M₂Fe(CO)₄, M = Na, K with elemental selenium in appropriate ratios lead to the formation of M₂[Fe₂(CO)₆(μ‐Se)₂]. Subsequent reactions with organo halides or the complex fragment cpFe(CO)₂⁺, cp = η⁵‐C₅H₅ afforded the selenolato complexes [Fe₂(CO)₆(μ‐SeR)₂], R = CH₂SiMe₃ ( 1 ), CH₂Ph ( 2 ), p‐CH₂C₆H₄NO₂ ( 3 ), o‐CH₂C₆H₄CH₂ ( 4 ) and cpFe(CO)₂⁺ ( 5 ) in moderate to good yields. A similar reaction employing Ru₃(CO)₁₂, Se and p‐O₂NC₆H₄CH₂Br leads to the formation of the corresponding organic diselenide. The X‐ray structures of 1 , 3 , 4 and 5 were determined and revealed butterfly structures of the Fe₂Se₂ cores. The substituents in 1 , 3  and 5 adopt different conformations depending on their steric demand. In 4 , the conformation is fixed because of the chelate effect of the ligand. The Fe–Se bond lengths lie in the range 235 to 240 pm, with corresponding Fe–Fe bond lengths of 254 to 256 pm. The ⁷⁷Se NMR data of the new complexes are discussed and compared with the corresponding data of related complexes.     

Synthesis of homoleptic tris(organo-chelate)iridium(III) complexes by spontaneous ortho-metallation of electronrich olefin-derived N,N′-diarylcarbene ligands and the X-ray structures of fac-[Ir{CN(C6H4Me-p) (CH2)2NC6H3Me-p}3] and mer-Ir{CN(C6H4Me-p)(CH2)2NC6H3Me-p}2 {CN(C6H4Me-p)(CH2)2NC6H4Me-p}Cl (a product of HCl cleavage)

Treatment of [{Ir(COD)(μ-Cl)}₂] with excess of the electron-rich olefin [$\text{CN(Ar)(CH}{}_2\text{)}{}_2\text{N}$Ar]₂ (abbreviated as (L^Ar)₂, Ar = C₆H₄Me-p or C₆H₄OMe-p) affords the ortho-metallated tricycle [$\text{Ir(L}{}^{\mathrm{A}}\text{r}$)₃], which for Ar = C₆H₄Me-p (Ia) with HCL yields [$\text{Ir(L}{}^{\mathrm{A}}\text{r}$)₂(L^Ar)]Cl (IV); X-ray data show that in IV there is an unexpectedly close Ir?C(o-aryl) contact (2;52(1) Å) involving the “free” L^Ar which compares with an IrC(o-aryl) distance of 2.09(3) Å in Ia or 2.07(3) Å in the ortho-metallated L^Ar ligand of complex IV.