Cp Me5P6C5[M(CO)5]3: Ungewöhnliche reaktion des tricyclischen hexaphosphans Cp2P6 mit M(CO)5thf (M = Cr,W)

3,4-Bis[pentamethylcyclopentadienyl]tricyclo-[3.1.0.0^2,6] hexaphosphane 1 reacts with Cr(CO)₅thf or W(CO)₅thf to give the zwitterionic chromium complex 1,9,10-tris(pentacarbonylchromium)−3,4,5,6,11-pentamethyl-7-pentamethylcyclopentadienyl-3,4,5,6,11-pentacarba-penta-cyclo-[6.1. 1.^1,8.1^3,6.O^2,7.0^10,11 ]-4-en-7-ium-9-id-undeca-phosphane 2 and the analogous tungsten compound 3, respectively. The basic structures of 2 and 3 are similar to the cunean-moiety of the Hittorf-modification of phosphorus.     

Darstellung und reaktionen von diphosphen-komplexen RPPR[M(CO)5]3 (M = Cr,Mo, W)

Decacarbonyldimetallates Na₂M₂(CO)₁₀ (M = Cr, Mo, W) react with dihalophosphanes, (R)P(Cl)₂, to yield trinuclear diphosphene complexes of the form RPPR[M(CO)₅]₃. The by-products of these reactions are diphosphane- and phosphido-bridged complexes.The trinuclear diphosphene compounds add HX (X = CH₃COO, CH₃O) or dienes to the PP double bond; in the course of these additions one M(CO)₅ group is cleaved and binuclear derivatives of diphosphanes are obtained.     

紫外激光诱导C60与M(CO)6(M=Cr,Mo, W)的配位反应

研究了用紫外激光(355 nm)诱导C_(60)与金属羰基化合物M(CO)_6(M＝Cr；Mo，W)的配位反应，合成了具有C_(4υ)对称性的配位络合物(η~2－C_(60))M(CO)_5，并初步讨论了C_(60)与M(CO)_6反应的动力学过程．     

The unusual electrochemical behaviour of [Co8(CO)18C]2− compared to [M6(CO)15C]2− (M = Co,Rh) and [Fe6(CO)16C]2− carbido clusters

A variety of electrochemical reactions has been observed for the carbido-carbonyl clusters [Co₈(CO)₁₈C](NMe₃CH₂C₆H₅)₂, [Co₆(CO)₁₅C](NMe₃CH₂C₆H₅)₂, [Rh₆(CO)₁₅C](Et₄N)₂ and [Fe₆(CO)₁₆C](Et₄N)₂. The hexanuclear clusters undergo irreversible electrochemical oxidation and reduction steps, whereas the octacobalt species exhibits three electrochemically reversible one-electron steps. The relation between the redox properties and the structure of these clusters is discussed.     

Ionic crystals [M3O(OOCC6H5)6(H2O)3]4[α-SiW12O40] (M = Cr, Fe) as heterogeneous catalysts for pinacol rearrangement

Complexation of trinuclear oxo-centered carboxylates with a silicododecatungstate resulted in the formation of ionic crystals of [M(3)O(OOCC(6)H(5))(6)(H(2)O)(3)](4)[α-SiW(12)O(40)]·nH(2)O·mCH(3)COCH(3) [M = Cr (Ia), Fe (IIa)]. Treatments of Ia and IIa at 373 K in vacuo formed guest-free phases Ib and IIb, respectively. Compounds Ib and IIb heterogeneously catalyzed the pinacol rearrangement to pinacolone with high conversion at 373 K, and the catalysis is suggested to proceed size selectively in the solid bulk.     

1H, 13C and 31P NMR studies of some (C6H5)3−nPRn and (C6H5)3−nPRn Cr(CO)5 (n = 0–3; R  H,CH3, C2H5, i-C3H7, t-C4H9) derivatives

The ³¹P chemical shift of the (C₆H₅)_3−nPR_n and (C₆H₅)_3−nPR_nCr(CO)₅ (n = 0–3; R  H, CH₃, C₂H₅, i-C₃H₇, t-C₄H₉) derivatives is dominated by the steric effect. A small inductive effect is also operative but there are no indications of notable (d_Cr→d_P)π back-bonding. The ¹³C chemical shift of the phenyl carbon atoms indicates that (p_ring-d_P)π electron delocalization is unimportant.The ¹³C chemical shift of the carbonyl carbon atoms, which is mainly governed by the mean excitation energy, confirms the conclusion that there are no notable changes in (d_Cr→d_P)π back-bonding in this series of compounds.     

Analysis of the metal–ligand bonds in [Mo(X)(NH2)3] (X = P, N, PO, and NO), [Mo(CO)5(NO)]+, and [Mo(CO)5(PO)]+

Quantum chemical calculations at the DFT level have been carried out for model complexes [Mo(P)(NH₂)₃] (1), [Mo(N)(NH₂)₃] (2), [Mo(PO)(NH₂)₃] (3), [Mo(NO)(NH₂)₃] (4), [Mo(CO)₅(PO)]⁺ (5), and [Mo(CO)₅(NO)]⁺ (6). The equilibrium geometries and the vibration frequencies are in good agreement with experimental and previous theoretical results. The nature of the Mo–PO, Mo–NO, Mo–PO⁺, Mo–NO⁺, Mo–P, and Mo–N bond has been investigated by means of the AIM, NBO and EDA methods. The NBO and EDA data complement each other in the interpretation of the interatomic interactions while the numerical AIM results must be interpreted with caution. The terminal Mo–P and Mo–N bonds in 1 and 2 are clearly electron-sharing triple bonds. The terminal Mo–PO and Mo–NO bonds in 3 and 4 have also three bonding contributions from a σ and a degenerate π orbital where the σ components are more polarized toward the ligand end and the π orbitals are more polarized toward the metal end than in 1 and 2. The EDA calculations show that the π bonding contributions to the Mo–PO and Mo–NO bonds in 3 and 4 are much more important than the σ contributions while σ and π bonding have nearly equal strength in the terminal Mo–P and Mo–N bonds in 1 and 2. The total (NH₂)₃Mo–PO binding interactions are stronger than for (NH₂)₃Mo–P which is in agreement with the shorter Mo–PO bond. The calculated bond orders suggest that there are only (NH₂)₃Mo–PO and (NH₂)₃Mo–NO double bonds which comes from the larger polarization of the σ and π contributions but a closer inspection of the bonding shows that these bonds should also be considered as electron-sharing triple bonds. The bonding situation in the positively charged complexes [(CO)₅Mo–(PO)]⁺ and [(CO)₅Mo–(NO)]⁺ is best described in terms of (CO)₅Mo → XO⁺ donation and (CO)₅Mo ← XO⁺ backdonation (X = P, N) using the Dewar–Chatt–Duncanson model. The latter bonds are stronger and have a larger π character than the Mo-CO bonds.     

Koordinationschemie tripodaler Triisocyanid-Liganden: Synthese von Komplexen des Typs CH3C[CH2NC-M(CO)x]3 (M = Cr,W, χ = 5; M = Fe, χ = 4) und Kristallstruktur von CH3C[CH2NC-W(CO)5]3

The triisocyanide ligand CH₃C(CH₂NC)₃, time, reacts with metal carbonyls M(CO)_x (M = Cr, W, χ = 6; M = Fe, χ = 5) to give the triply metal carbonyl substituted complexes CH₃C[CH₂NCM(CO)_x]₃ (M = Cr, W, χ = 5; M = Fe, χ = 4). CH₃C[CH₂NCW(CO)₅]₃ was characterized by an X-ray structure determination.     

金属羰基化合物M(CO)6(M=Cr,Mo, W)氧原子转移反应动力学与机理

本文研究了PPh3存在与不存在的情况下, M(CO)6(M=Cr, Mo, W)与三甲胺氧化物me3NO在CH2Cl2中的氧原子转移反应动力学. 反应速率遵循: r=k[M(CO)6][Me3NO], 并且rW>rMo>rCr, 并根据实验结果提出了反应机理, 讨论了溶剂对反应速率的影响.     

Correlation between solvatochromism and back-bonding in four isomeric (α-diimine)M(CO)4 complexes,M = Cr,Mo, W

Long-wavelength charge transfer absorption energies of isomeric complexes (bidiazine)M(CO)₄, (bidiazine = 3,3′-bipyridazine, 2,2′- and 4,4′-bipyrimidine, 2,2′-bipyrazine; M = Cr, Mo, W) were measured in various solvents and compared with those for corresponding 2,2′-bipyridine complexes. Linear correlations of energies of absorption maxima with solvent parameters E_MLCT revealed that the solvent dependence Δυ/gDE_MLCT within the bidiazine series increases with decreasing absolute charge transfer transition energy in a given solvent, i.e. with increasing back-donation into the ligand π orbital. Complexes of the most strongly back-bonding ligand, 4,4′-bipyrimidine, thus display by far the most pronounced solvent dependence, with Δυ/gdE_MLCT 4100 cm ⁻¹ for the molybdenum system.     

Reaction of Mo(CO)6 with Alkoxide: Synthesis and Structure of the Mo(0)-OR Complex [Et4N]3[Mo2(CO)6(μ-OC6H4OCH2C6H5)3]

The reaction of molybdenum hexacarbonyl with C6H5CH2OC6H4ONa and Et4NBr in CH3CN at 60 ℃ afforded the di-nuclear Mo(0) compound [Et4N]3[Mo2(CO)6(μ-OC6H4OCH2- C6H5)3] 1. 1 crystallizes in monoclinic, space group P21/c with a=15.359(2), b=18.378(3), c=24.952(2)(A), β=102.268(4)°, V=6882.3(16) (A)3, Mr=1348.34, Z=4, Dc=1.301 g/cm3, F(000)=2832 and μ= 0.424 mm-1. The final R=0.0606 and wR=0.1552 for 9396 observed reflections (Ⅰ ＞ 2σ(Ⅰ)). 1 contains a [Mo2O3]3- core in triangular bi-pyramidal configuration and each Mo atom adopts a distorted octahedral geometry with three carbon atoms from carbonyls and three μ-O atoms from C6H5CH2OC6H4O- bridging ligands. The Mo…Mo distance is 3.30(8) (A), indicating no metalmetal bonding. A formation pathway via forming a di-molybdenum(0) di-bridging OR compound [Mo2(μ-OR)2(CO)8]2- has been figured out and the reaction of Mo(CO)6 with alkoxide has also been discussed.     

Fluorinated Mono and Spirocyclic Δ5[sgrave]5P and Δ5[sgrave]6P Derivatives of (HO)3−nHnPO (n= 0−3)

Abstract

The properties of PF₅, HPF₄, H₂PF₃, and H₃PF₂ (Δ⁵[sgrave]⁵P derivatives of (HO)₃PO, (HO)₂HPO, (HO)H₂PO, and of the hypothetic H₃PO) and the formation of the related Δ⁵[sgrave]⁶P anions PF₆ ^–, HPF₅ ^–, and trans-H₂PF₄ ^– have been studied some years ago ^1–4. The mono and spirocyclic dioxa and tetraoxa analogues, 1 and 2 available from the corresponding precursor phosphoranes by fluoride addition could be found also as products in the reaction of phosphite 3⁵ and K⁺(CF₃)₂CFO^– together with two other phosphates, 4 and 5. A ¹⁹F–¹⁹F homocorrelated 2 D NMR spectrum of 2 indicated coupling of the P–F fluorine nuclei with two CF₃ groups by a non bond mechanism.     

Hetero- and homobimetallic M/Ni,M/M (M = Mo,W) μ-alkyne complexes containing functionally substituted cyclopentadienyl ligands. Crystal structure of η5-2,4-(NO2)2C6H3NHNC(Me)C5H4(CO)2WFe2H(μ3-S)(CO)6

While reaction of [⁵-RC₅H₄(CO)₃Mo]₂, PhCCPh and Cp₂Ni yields Mo/Ni hetero- and Mo/Mo homobimetallic complexes [⁵-RC₅H₄(CO)₂MoNiCp](-C₂Ph₂) [(1a) R = MeCO; (1b) R = MeO₂C] and [⁵-RC₅H₄(CO)₂Mo]₂(-C₂Ph₂) [(2a) R = MeCO; (2b) R = MeO₂C], reaction of [⁵-RC₅H₄(CO)₃W]₂, PhCCPh and Cp₂Ni give W/Ni heterobimetallic compounds [⁵-RC₅H₄(CO)₂WNiCp](-C₂Ph₂) [(3a) R = MeCO; (3b) R = EtO₂C] without an appreciable amount of W/W homobimetallic complexes [⁵-RC₅H₄(CO)₂W]₂(-C₂Ph₂) [(4a) R = MeCO; (4b) R = EtO₂C]. However, (4a) and (4b) can be simply obtained from [⁵-RC₅H₄(CO)₃W]₂ and PhCCPh in quite good yields. Further, reactions of (1a) and (3a) with 2,4-(NO₂)₂C₆H₃NHNH₂ produce phenylhydrazone derivatives [⁵-2,4-(NO₂)₂C₆H₃NHNC(Me)C₅H₄(CO)₂MNiCp](-C₂Ph₂) [(5a) M = Mo, (5b) M = W], whereas reactions of (2a) and (4a) with 2,4-(NO₂)₂C₆H₃NHNH₂ give corresponding derivatives [⁵-2,4-(NO₂)₂C₆H₃NHNC(Me)C₅H₄(CO)₂MM(CO)₂C₅H₄COMe-⁵](-C₂Ph₂) [(6a) M = Mo, (6b) M = W] and [⁵-2, 4-(NO₂)₂C₆H₃NHNC(Me)C₅H₄(CO)₂M]₂(-C₂ Ph₂) [(7a) M = Mo, (7b) M = W]. The crystal structure of ⁵-2,4-(NO₂)₂C₆H₃NHNC(Me)C₅H₄(CO)₂WFe₂H (₃-S)(CO)₆ (8) has been determined by X-ray diffraction.     

Synthesis and characterisation of [AgL(μ-PR2)M(CO)5], L= 1,10-phenanthroline or tricyclohexylphosphine; M = Cr,Mo, W

The new heterobimetallic phosphide-bridged compounds [AgL(μ-PR₂)M(CO)₅], (L = 1,10-phenanthroline or tricyclohexylphosphine: M = Cr, M, W) have been prepared from AgO₃SCF₃, M(CO)₅PR₂H and the ligand L in the presence of Et₂NH or MeO⁻ as base, and characterized by ³¹P NMR spectroscopy.     

The Synthesis of the Arene Clusters Ru6C(CO)14(η6-Arene) (Arene = C6H5CHMe2, C6H5C4H9, C6H5C3H7, and C6H5C3H5)

On reaction with Ru₃(CO)₁₂, isopropenylbenzene and 4-phenyl-l-butene undergo hydrogenation, to yield the clusters, Ru₆C(CO)₁₄(⁶-C₆H₅CHMe₂) 1 and Ru₆C(CO)₁₄(⁶-C₆H₅C₄H₉) 2, respectively. With allylbenzene, both hydrogenation and isomerization occurs affording Ru₆C(CO)₁₄(⁶-C₆H₅C₃H₇) 3 and Ru₆C(CO)14(⁶-C₆H₅C₃H₅) 4. The structures of 1 and 2 have been established by single crystal X-ray diffraction. One of the Ru–Ru bond lengths in 2 is unusually long and extended Hückel molecular orbital calculations have been used in an attempt to rationalize this feature.     

About the Reaction of C(PPh3)2 with [M(CO)6] (M = Cr,Mo): Unusual Formation of μ-Carbonato Complexes of Mo under Participation of THF

Attempts to synthesize complexes of group 6 carbonyl compounds [M(CO)₆] (M = Cr, Mo, W) with the carbone C(PPh₃)₂ ( 1 ) via the photo chemically created adducts [(CO)₅M(THF)] lead to quantitative formation of the salts [HC(PPh₃)₂]₂[M₂(CO)₁₀] ( 2 , Cr; 3 , Mo; 4 , W). Alternatively, a long-time thermal reaction of [Mo(CO)₆] performed with 1 in THF generates a series of products initiated by a Wittig-type reaction. In addition to 3 , minor amounts of [(CO)₅MoCCPPh₃] ( 8 ), [(CO)₅MoO₂CC{PPh₃}₂] ( 5 ), and the carbonate complexes [HC(PPh₃)₂]₂[(CO)₅Mo(CO₃)Mo(CO)₄] ( 6 ) and [HC(PPh₃)₂]₂[(CO)₄Mo(CO₃)Mo(CO)₄] ( 7 ) were found. Compounds 2 , 3 , 5 , 6 , and 7 were characterized by X-ray analyses, ³¹P NMR, and IR spectroscopy. The water, necessary for the formation of the carbonate, stems from decomposition of THF.     

Homogeneous catalysis by transition metal complexes. Part VI: Hydroformylation of 1-octene catalysed by [η5-C5R5M(CO)2X] and [η5-C5R5M(CO)2]2 species (R = H,CH3, C6H5; M = Fe,Ru; X = Cl,Br, I)

The hydroformylation of 1-octene catalysed by the title compounds has been examined at 135 °C under an atmosphere of H₂ and CO at a pressure of 85 atm. The influence on the activity and selectivity of various parameters such as the nature of the metal, the nuclearity of the original complex and the electronic and steric effects induced by the substituents on the cyclopentadienyl ligand has been investigated and discussed.     

Pressure tuning spectroscopy of [Pt3(CO)6]2−n (n=3–5)

The pressure shifts of the first three bands appearing in the visible spectra of [Pt₃(CO)₆]²⁻_n (n = 3–5) have been measured in solution over the range 0–10 kbar. Previous electronic calculations performed on the dimer in conjunction with these results afford a possible set of assignments for the first three bands appearing in the visible spectrum for the dimer.     

REACTIONS OF [η5−RC5H4 (CO)2Mo]2 (Mo≡Mo) WITH (μ-PhSe)2Fe2 (CO)6. SYNTHESIS AND CHARACTERIZATION OF SELENOLATO-BRIDGED TRANSITION METAL COMPLEXES [η5−RC5H4Mo (CO) (μ-SePh)]2 (R ˭ MeCO,MeO2C) AND η5−RC5H4MoFe2 (CO)4 (μ3-Se) [μ,η1: η2−C(0)Ph] (μ-SePh)2 (R ˭ H,MeCO, EtO2C)

Abstract

Mo≡Mo triply bonded dimers [η⁵?RC₅H₄ —react with (μ,-PhSe)₂Fe₂ (CO)₆ in boiling xylene to give selenolato-bridged bimetallic complexes [η⁵?RC5H₄Mo(CO) (μ-SePh)]₂ (R ? MeCO, MeO₂C). However, irradiation of a benzene solution of —(R ? H, MeCO, EtO₂C) and (μ-PhSe)₂Fe₂ (CO)₆ with a 400W high pressure mercury lamp gave rise to selenolato-bridged trimetallic clusters η⁵?RC₅H₄MoFe₂(CO)₂ (μ₃-Se) [μ,η:η²?C (O) Ph] (μ-SePh)₂ (R ? H, MeCO, EtO₂C). All products were characterized by elemental analysis and spectroscopic methods, as well as by an X-ray diffraction analysis of the product η⁵?MeCOC₅H₄MoFe₂(CO)₄ (μ-Se)[μ;η¹:η²?C(O)Ph](μ-SePh)₂.     

Interpretation der Absorptionsspektren der Komplexionen [Mo(CN)8]4−, [Mo(CN)8]3−, [W(CN)8]4− und [W(CN)8]3−

Zusammenfassung Die Absorptions- und Reflexionsspektren der Oktocyanokomplexe desMo(IV) undW(IV) sowie die Absorptionsspektren der Oktocyanotomplexe desMo(V) undW(V) werden mitgeteilt. Die Spektren werden unter Zugrundelegung der durch Raman- und IR-spektroskopische Untersuchungen gefordertenD _4d-Symmetrie dieser Verbindungen interpretiert. Die beobachteten Banden niedriger Intensität (log<3) werden Übergängen in einem Termsystem zugeordnet, das für die Konfigurationend ² undd ₁ und die SymmetrieD _4d berechnet worden ist. Banden hoher Intensität (log>3) werden auf Übergänge in antibindende Zustände zurückgeführt, an denen höherep-Zustände des Zentralions sowie Ligandenzustände beteiligt sind. Die erhaltenen Werte des Feldparameters stimmen mit ligandenfeldtheoretischen Erwartungen überein.

---

Absorption and reflection spectra of the octacyanides ofMo(IV) andW(IV) and the absorption spectra of the octacyanides ofMo(V) andW(V) are presented. The spectra are interpreted in terms of theD _4d symmetry of the compounds supported by investigations of Raman and infrared spectra. Bands of low intensity (log<3) correspond to transitions between levels obtained in the case of the configurationsd ² andd ¹ respectively, in a field ofD _4d symmetry. Bands of high intensity (log>3) are attributed to transitions into antibonding levels in which p-orbitals of the central ion and ligand orbitals participate. The values of the field parameter obtained are in accord with ligand field theory.

---

Résumé Les spectres d'absorption et de réflexion des complexes octocyanurés duMo(IV) et duW(IV) ainsi que les spectres d'absorption des mêmes complexes deMo(V) et de W(V) sont présentés. Les spectres sont interprétés en supposant la symétrieD _4d des molécules indiquée par des analyses des spectres Raman et infrarouges. Les bandes de faible intensité (log<3) sont attribuées à des transitions dans un système de niveaux, calculé pour les configurationsd ² etd ¹, respectivement, en symétrieD _4d. Des bandes de forte intensité (log>3) sont attribuées à des transitions vers des niveaux antiliants auxquels participent des fonctions élevéesp de l'ion central et des fonctions des groupes liés. Les valeurs obtenues pour le paramètre de champ sont en accord avec les prévisions de la théorie.