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1.
A μ3‐η222‐silane complex, [(Cp*Ru)33‐η222‐H3SitBu)(μ‐H)3] ( 2 a ; Cp*=η5‐C5Me5), was synthesized from the reaction of [{Cp*Ru(μ‐H)}33‐H)2] ( 1 ) with tBuSiH3. Complex 2 a is the first example of a silane ligand adopting a μ3‐η222 coordination mode. This unprecedented coordination mode was established by NMR and IR spectroscopy as well as X‐ray diffraction analysis and supported by a density functional study. Variable‐temperature NMR analysis implied that 2 a equilibrates with a tautomeric μ3‐silyl complex ( 3 a ). Although 3 a was not isolated, the corresponding μ3‐silyl complex, [(Cp*Ru)33‐η22‐H2SiPh)(H)(μ‐H)3] ( 3 b ), was obtained from the reaction of 1 with PhSiH3. Treatment of 2 a with PhSiH3 resulted in a silane exchange reaction, leading to the formation of 3 b accompanied by the elimination of tBuSiH3. This result indicates that the μ3‐silane complex can be regarded as an “arrested” intermediate for the oxidative addition/reductive elimination of a primary silane to a trinuclear site.  相似文献   

2.
The reaction of PPh2Cl with orthomanganated acetophenone, 2′-CH3C(O)C6H4Mn(CO)4, gives Mn2(μ-η11-Ph2PPPh2)(μ-Cl)2(CO)6. An X-ray structure determination [triclinic, space group P1 , a = 10.908(4) Å, b = 11.756(3) Å, c = 12.186(3) Å, α = 96.20(2)°, β = 99.51(2)°, γ = 96.52(2)°] shows two Mn(CO)3 groups held together by two bridging Cl ligands, and further bridged by a Ph2P? PPh2 group prepared in situ.  相似文献   

3.
The reactivity of two paramagnetic nickel(I) compounds, CpNi(NHC) (where Cp=cyclopentadienyl; NHC=1,3‐bis(2,4,6‐trimethylphenyl)imidazol‐2‐ylidene (IMes) or 1,3‐bis(2,6‐diisopropylphenyl)imidazol‐2‐ylidene (IPr)), towards [Na(dioxane)x][PnCO] (Pn=P, As) is described. These reactions afford symmetric bimetallic compounds (μ222‐Pn2){Ni(NHC)(CO)}2. Several novel intermediates en route to such species are identified and characterised, including a compound containing the PCO? anion in an unprecedented μ222‐binding mode. Ultimately, on treatment of the (μ222‐Pn2){Ni(IMes)(CO)}2 compounds with carbon monoxide, the Pn2 units can be released, affording P4 in the case of the phosphorus‐containing species, and elemental arsenic in the case of (μ222‐As2){Ni(IMes)(CO)}2.  相似文献   

4.
The synthesis and single crystal X‐ray structure determination are reported for the 2,2′ : 6′,2″‐terpyridine (= tpy) adduct of bismuth(III) nitrate. The hydroxide‐bridged dimer [(η2‐NO3)2(tpy)Bi(μ‐OH)2Bi(tpy)(η2‐NO3)2] with nine‐coordinate geometry about Bi was the only isolable product from all crystallization attempts in varying ratios of Bi(NO3) : terpy.; [(η2‐NO3)2(tpy)Bi(μ‐OH)2Bi(tpy) · (η2‐NO3)2] is triclinic, P 1, a = 7.941(8), b = 10.732(9), c = 11.235(9) Å; α = 63.05(1), β = 85.01(1), γ = 79.26(1)°, Z = 1, dimer, R = 0.058 for N0 = 2319.  相似文献   

5.
Tris)(η 5-cyclopentadienyl-μ-carbonyl-iron)-μ3-nitrosyl cluster was obtained from the reaction of cyclopentadienyl dicarbonyliron dimer with nitrogen monoxide in xylene. The cluster was characterized by elemental analyses, IR, MS and 1H NMR. The crystal structure of [(η5-C5H5)(μ-CO)Fe]3(μ3-NO).C4H8O was determined by X-ray diffraction analysis. It crystallizes in the orthorhombic space group Pnma, a=9.053(2), 6=10.545(2), c=22.525(4) A, V=2150.3(7) A3, Z=4,Dc=1.68 g.cm-3; structure solution and refinement based on 1141 reflections with I > 3.0 (I) (MoKa, A=0.71073 A) converged at R=0.0540. The infrared absorption band at 1325 cm-1 of the μ3-NO in the cluster, which is red shifted, shows that μ3-NO is activated.  相似文献   

6.
The first doubly‐bridged thiocarbamoyl metal complex [Mo(Cl)(CO)2(PPh3)]212:μ‐SCNMe2)2 ( 2 ) was formed from stirring [Mo(CO)22‐SCNMe2)(PPh3)2Cl] ( 1 ) in dichloromethane at room temperature. Complex 2 is a dimer with each thiocarbamoyl unit coordinating through sulfur and carbon to one metal center and bridging both metals through sulfur. Complex 2 is characterized by X‐ray diffraction analysis.  相似文献   

7.
Two series of new dinuclear rare‐earth metal alkyl complexes supported by indolyl ligands in novel μ‐η211 hapticities are synthesized and characterized. Treatment of [RE(CH2SiMe3)3(thf)2] with 1 equivalent of 3‐(tBuN?CH)C8H5NH ( L1 ) in THF gives the dinuclear rare‐earth metal alkyl complexes trans‐[(μη211‐3‐{tBuNCH(CH2SiMe3)}Ind)RE(thf)(CH2SiMe3)]2 (Ind=indolyl, RE=Y, Dy, or Yb) in good yields. In the process, the indole unit of L1 is deprotonated by the metal alkyl species and the imino C?N group is transferred to the amido group by alkyl CH2SiMe3 insertion, affording a new dianionic ligand that bridges two metal alkyl units in μη211 bonding modes, forming the dinuclear rare‐earth metal alkyl complexes. When L1 is reduced to 3‐(tBuNHCH2)C8H5NH ( L2 ), the reaction of [Yb(CH2SiMe3)3(thf)2] with 1 equivalent of L2 in THF, interestingly, generated the trans‐[(μη211‐3‐{tBuNCH2}Ind)Yb(thf)(CH2SiMe3)]2 (major) and cis‐[(μη211‐3‐{tBuNCH2}Ind)Yb(thf)(CH2SiMe3)]2 (minor) complexes. The catalytic activities of these dinuclear rare‐earth metal alkyl complexes for isoprene polymerization were investigated; the yttrium and dysprosium complexes exhibited high catalytic activities and high regio‐ and stereoselectivities for isoprene 1,4‐cis‐polymerization.  相似文献   

8.
Syntheses, Structure and Reactivity of η3‐1,2‐Diphosphaallyl Complexes and [{(η5‐C5H5)(CO)2W–Co(CO)3}{μ‐AsCH(SiMe3)2}(μ‐CO)] Reaction of ClP=C(SiMe2iPr)2 ( 3 ) with Na[Mo(CO)35‐C5H5)] afforded the phosphavinylidene complex [(η5‐C5H5)(CO)2Mo=P=C(SiMe2iPr)2] ( 4 ) which in situ was converted into the η1‐1,2‐diphosphaallyl complex [η5‐(C5H5)(CO)2Mo{η3tBuPPC(SiMe2iPr)2] ( 6 ) by treatment with the phosphaalkene tBuP=C(NMe2)2. The chloroarsanyl complexes [(η5‐C5H5)(CO)3M–As(Cl)CH(SiMe3)2] [where M = Mo ( 9 ); M = W ( 10 )] resulted from the reaction of Na[M(CO)35‐C5H5)] (M = Mo, W) with Cl2AsCH(SiMe3)2. The tungsten derivative 10 and Na[Co(CO)4] underwent reaction to give the dinuclear μ‐arsinidene complex [(η5‐C5H5)(CO)2W–Co(CO)3{μ‐AsCH(SiMe3)2}(μ‐CO)] ( 11 ). Treatment of [(η5‐C5H5)(CO)2Mo{η3tBuPPC(SiMe3)2}] ( 1 ) with an equimolar amount of ethereal HBF4 gave rise to a 85/15 mixture of the saline complexes [(η5‐C5H5)(CO)2Mo{η2tBu(H)P–P(F)CH(SiMe3)2}]BF4 ( 18 ) and [Cp(CO)2Mo{F2PCH(SiMe3)2}(tBuPH2)]BF4 ( 19 ) by HF‐addition to the PC bond of the η3‐diphosphaallyl ligand and subsequent protonation ( 18 ) and/or scission of the PP bond by the acid ( 19 ). Consistently 19 was the sole product when 1 was allowed to react with an excess of ethereal HBF4. The products 6 , 9 , 10 , 11 , 18 and 19 were characterized by means of spectroscopy (IR, 1H‐, 13C{1H}‐, 31P{1H}‐NMR, MS). Moreover, the molecular structures of 6 , 11 and 18 were determined by X‐ray diffraction analysis.  相似文献   

9.
Lanthanoid Peroxo Complexes with μ3‐η222‐(O22—) Coordination. Crystal Structures of [Ln4(O2)2Cl8(Py)10] · Py mit Ln = Sm, Eu, Gd The four‐nuclear peroxo complexes [Ln4(O2)2Cl8(Py)10]·py (py = pyridine) with Ln = Sm ( 1 ·py), Eu ( 2 ·py) und Gd ( 3 ·py) are formed as pale yellow ( 1 ·py) and colourless ( 2 ·py and 3 ·py) crystals by action of atmospheric oxygen on heated solutions of the anhydrous trichlorides LnCl3 in pyridine/ diacetone alcohol (4‐hydroxy‐4‐methyl‐2‐pentanone). According to the X‐ray structural analyses the three complexes crystallize isostructural in the triclinic space group PP1¯ with two formula units per unit cell. 1—3 form centrosymmetrical molecular structures, in which the four lanthanoid atoms in coplanar array are linked via the two peroxo groups in a hitherto unobserved μ3‐η222 coordination. Additionally, they are bonded by four �μchloro bridges. Two of the Ln atoms complete their coordination sphere by three pyridine molecules each, the other two by two chlorine atoms and two pyridine molecules. The gadolinium compound is additionally characterized by its complete vibrational spectrum (i.r. and Raman).  相似文献   

10.
Based on the equilibrium geometries of [Cu2(dbdmed)2O2]2+ and [Cu2(en)2O2]2+ obtained within density‐functional theory, we investigate their molecular electronic structure and optical response. Thereby results from occupation‐constrained as well as time‐dependent DFT (ΔSCF and TDDFT) are compared with Green's function‐based approaches within many‐body perturbation theory such as the GW approximation (GWA) to the quasiparticle energies and the Bethe‐Salpeter equation (BSE) approach to the optical absorption. Concerning the ground‐state energies and geometries, no clear trend with respect to the amount of exact exchange in the DFT calculations is found, and a strong dependence on the basis sets is to be noted. They affect the energy difference between bis‐μ‐oxo and μ‐η22‐peroxo complexes by as much as 0.8 eV (18 kcal/mol). Even stronger, up to 5 eV is the influence of the exchange‐correlation functional on the gap values obtained from the Kohn‐Sham eigenvalues. Not only the value itself but also the trends observed upon the bis‐μ‐oxo to μ‐η22‐peroxo transition are affected. In contrast, excitation energies obtained from ΔSCF and TDDFT are comparatively robust with respect to the details of the calculations. Noteworthy, in particular, is the near quantitative agreement between TDDFT and GWA+BSE for the optical spectra of [Cu2(en)2O2]2+. © 2013 Wiley Periodicals, Inc.  相似文献   

11.
The title compounds, [Cr(C12H10)(CO)3] and [Cr2(C12H10)(CO)6], serve as a fundamental standard of comparison for other mono‐ and polysubstituted (η6‐bi­phenyl)­tri­carbonyl­chromium compounds. (η6‐Bi­phenyl)­tri­carbonyl­chromium has a typical piano‐stool coordination about the Cr center, and the dihedral angle between the planes of the phenyl rings is 23.55 (5)°. The corresponding angle in μ‐(η66)‐bi­phenyl‐bis­(tri­carbonyl­chromium) is 0° because the mol­ecule occupies a crystallographic inversion center; the Cr atoms reside on opposite sides of the bi­phenyl ligand. Density functional theory and natural bonding orbital theory analyses were used to scrutinize the geometry of these and closely related compounds to explain important structural features.  相似文献   

12.
The η2‐thio‐indium complexes [In(η2‐thio)3] (thio = S2CNC5H10, 2 ; SNC4H4, (pyridine‐2‐thionate, pyS, 3 ) and [In(η2‐pyS)22‐acac)], 4 , (acac: acetylacetonate) are prepared by reacting the tris(η2‐acac)indium complex [In(η2‐acac)3], 1 with HS2CNC5H10, pySH, and pySH with ratios of 1:3, 1:3, and 1:2 in dichloromethane at room temperature, respectively. All of these complexes are identified by spectroscopic methods and complexes 2 and 3 are determined by single‐crystal X‐ray diffraction. Crystal data for 2 : space group, C2/c with a = 13.5489(8) Å, b = 12.1821(7) Å, c = 16.0893(10) Å, β = 101.654(1)°, V = 2600.9(3) Å3, and Z = 4. The structure was refined to R = 0.033 and Rw = 0.086; Crystal data for 3 : space group, P21 with a = 8.8064 (6) Å, b = 11.7047 (8) Å, c = 9.4046 (7) Å, β = 114.78 (1)°, V = 880.13(11) Å3, and Z = 2. The structure was refined to R = 0.030 and Rw = 0.061. The geometry around the metal atom of the two complexes is a trigonal prismatic coordination. The piperidinyldithiocarbamate and pyridine‐2‐thionate ligands, respectively, coordinate to the indium metal center through the two sulfur atoms and one sulfur and one nitrogen atoms, respectively. The short C‐N bond length in the range of 1.322(4)–1.381(6) Å in 2 and C‐S bond length in the range of 1.715(2)–1.753(6) Å in 2 and 3 , respectively, indicate considerable partial double bond character.  相似文献   

13.
We report the synthesis of [n]manganoarenophanes (n=1, 2) featuring boron, silicon, germanium, and tin as ansa‐bridging elements. Their preparation was achieved by salt‐elimination reactions of the dilithiated precursor [Mn(η5‐C5H4Li)(η6‐C6H5Li)]?pmdta (pmdta=N,N,N′,N′,N′′‐pentamethyldiethylenetriamine) with corresponding element dichlorides. Besides characterization by multinuclear NMR spectroscopy and elemental analysis, the identity of two single‐atom‐bridged derivatives, [Mn(η5‐C5H4)(η6‐C6H5)SntBu2] and [Mn(η5‐C5H4)(η6‐C6H5)SiPh2], could also be determined by X‐ray structural analysis. We investigated for the first time the reactivity of these ansa‐cyclopentadienyl–benzene manganese compounds. The reaction of the distannyl‐bridged complex [Mn(η5‐C5H4)(η6‐C6H5)Sn2tBu4] with elemental sulfur was shown to proceed through the expected oxidative addition of the Sn?Sn bond to give a triatomic ansa‐bridge. The investigation of the ring‐opening polymerization (ROP) capability of [Mn(η5‐C5H4)(η6‐C6H5)SntBu2] with [Pt(PEt3)3] showed that an unexpected, unselective insertion into the Cipso?Sn bonds of [Mn(η5‐C5H4)(η6‐C6H5)SntBu2] had occurred.  相似文献   

14.
1H‐1, 3‐Benzazaphospholes react with M(CO)5(THF) (M = Cr, Mo, W) to give thermally and relatively air stable η1‐(1H‐1, 3‐Benzazaphosphole‐P)M(CO)5 complexes. The 1H‐ and 13C‐NMR‐data are in accordance with the preservation of the phosphaaromatic π‐system of the ligand. The strong upfield 31P coordination shift, particularly of the Mo and W complexes, forms a contrast to the downfield‐shifts of phosphine‐M(CO)5 complexes and classifies benzazaphospholes as weak donor but efficient acceptor ligands. Nickelocene reacts as organometallic species with metalation of the NH‐function. The resulting ambident 1, 3‐benzazaphospholide anions prefer a μ2‐coordination of the η5‐CpNi‐fragment at phosphorus to coordination at nitrogen or a η3‐heteroallyl‐η5‐CpNi‐semisandwich structure. This is shown by characteristic NMR data and the crystal structure analysis of a η5‐CpNi‐benzazaphospholide. The latter is a P‐bridging dimer with a planar Ni2P2 ring and trans‐configuration of the two planar heterocyclic phosphido ligands arranged perpendicular to the four‐membered ring.  相似文献   

15.
The reaction of the thiocarbamoyl‐molybdenum complex [Mo(CO)22‐SCNMe2)(PPh3)2Cl] 1 , with EtOCS2K and C4H8NCS2NH4 in dichloromethane at room temperature yielded the seven coordinated ethyldithiocarbonate thiocarbamoyl‐molybdenum complex [Mo(CO)22‐S2COEt)(η2‐SCNMe2)(PPh3)] 2 , and the dithiocarbamate thiocarbamoyl‐molybdenum complex [Mo(CO)22‐S2CNC4H8)(η2‐SCNMe2)(PPh3)] 3 . The geometry around the metal atom of compounds 2 and 3 are capped octahedrons as revealed by X‐ray diffraction analyses. The thiocarbamoyl and ethyldithiocarbonate or pyrrolidinyldithiocarbamate ligands coordinate to the molybdenum metal center through the carbon and sulfur and two sulfur atoms, respectively. Structure parameters, NMR, IR and Mass spectra are in agreement with the crystal chemistry of the two compounds.  相似文献   

16.
In the title compound, [Mn(C5H2N2O4)(H2O)2]n, the MnII ion has a distorted octahedral geometry and the 4‐oxido‐2‐oxo‐1,2‐dihydropyrimidine‐5‐carboxylate (Hiso2−) anion acts as a μ34‐bridging ligand. Two oxo O atoms from different Hiso2− ligands bridge two MnII ions, forming centrosymmetric dinuclear building blocks. Each dinuclear building block interacts with another four by the coordination of the oxide groups and carboxylate O atoms, producing a two‐dimensional framework in the ab plane. Hydrogen bonds further extend the two‐dimensional sheets into a three‐dimensional supramolecular framework.  相似文献   

17.
The synthesis of ansa complexes has been studied intensively owing to their importance as homogeneous catalysts and as precursors of metal‐containing polymers. However, paramagnetic non‐metallocene derivatives are rare and have been limited to examples with vanadium and titanium. Herein, we report an efficient procedure for the selective dilithiation of paramagnetic sandwich complex [Cr(η5‐C5H5)(η6‐C6H6)], which allows the preparation of a series of [n]chromoarenophanes (n=1, 2, 3) that feature silicon, germanium, and tin atoms at the bridging positions. The electronic and structural properties of these complexes were probed by X‐ray diffraction analysis, cyclic voltammetry, and by UV/Vis and EPR spectroscopy. The spectroscopic parameters for the strained and less strained complexes (i.e., with multiple‐atom linkers) indicate that the unpaired electron resides primarily in a d orbital on chromium(I); this result was also supported by density functional theory (DFT) calculations. We did not observe a correlation between the experimental UV/Vis and EPR data and the degree of molecular distortion in these ansa complexes. The treatment of tin‐bridged complex [Cr(η5‐C5H4)(η6‐C6H5)SntBu2] with [Pt(PEt3)3] results in the non‐regioselective insertion of the low‐valent Pt0 fragment into the Cipso? Sn bonds in both the five‐ and six‐membered rings, thereby furnishing a bimetallic complex. This observed reactivity suggests that ansa complexes of this type are promising starting materials for the synthesis of bimetallic complexes in general and also underline their potential to undergo ring‐opening processes to yield new metal‐containing polymers.  相似文献   

18.
Treatment of Pd(PPh3)4 with 5‐bromo‐pyrimidine [C4H3N2Br] in dichloromethane at ambient temperature cause the oxidative addition reaction to produce the palladium complex [Pd(PPh3)21‐C4H3N2)(Br)], 1 , by substituting two triphenylphosphine ligands. In acetonitrile solution of 1 in refluxing temperature for 1 day, it do not undergo displacement of the triphenylphosphine ligand to form the dipalladium complex [Pd(PPh3)Br]2{μ,η2‐(η1‐C4H3N2)}2, or bromide ligand to form chelating pyrimidine complex [Pd(PPh3)22‐C4H3N2)]Br. Complex 1 reacted with bidentate ligand, NH4S2CNC4H8, and tridentate ligand, KTp {Tp = tris(pyrazoyl‐1‐yl)borate}, to obtain the η2‐dithiocarbamate η1‐pyrimidine complex [Pd(PPh3)(η1‐C4H3N2)(η2‐S2CNC4H8)], 4 and η2‐Tp η1‐pyrimidine complex [Pd(PPh3)(η1‐C4H3N2)(η2‐Tp)], 5 , respectively. Complexes 4 and 5 are characterized by X‐ray diffraction analyses.  相似文献   

19.
Heterometallic Cluster Complexes of the Types Re2(μ-PR2)(CO)8(HgY) and ReMo(μ-PR2)(η5-C5H5)(CO)6(HgY) (R = Ph, Cy; Y = Cl, W(η5-C5H5)(CO)3) Dinuclear complexes Re2(μ-H)(μ-PR2)(CO)8 and ReMo(μ-H)(μ-PR2)(η5-C5H5)(CO)6 (R = phenyl, cyclohexyl) were deprotonated and reacted as anions with HgCl2 to compounds of the both types Re2(μ-PR2)(CO)8HgCl) and ReMo(μ-PR2)(η5-C5H5)(CO)6(HgCl). The heterometallic three-membered cluster complexes correspond to an isolobal exchange of a proton against a cationic HgCl+ group. For one of the products ReMo(μ-PCy2)(η5-C5H5)(CO)6(HgCl) has been shown its conversion with NaW(η5-C5H5)(CO)3 to ReMo(μ-PCy2)(η5-C5H5)(HgW(η5-C5H5)(CO)3) under substitution of the chloro ligand, par example. The newly prepared compounds were characterized by means of IR, UV/VIS and 31P NMR data. A complete determination of the molecular structure by single crystal analyses was done in the case of Re2(μ-PCy2)(CO)8(HgCl) and of ReMo(μ-PCy2)(η5-C5H5)(CO)6(HgCl) which both are dimer because of the presence of an asymmetric dichloro bridge, and of ReMo(μ-PCy2)(η5-C5H5)(CO)6(HgW(η5-C5H5)(CO)3). The structural study illustrates through comparison the influence of various metal types on an interaction between centric and edge-bridged frontier orbitals in three-membered metal rings.  相似文献   

20.
Reaction of Mo(CO)(η2‐C2Ph2)24‐C4Ph4) and Me3NO in acetonitrile solvent affords Mo(NCMe)(η2‐C2Ph2)24‐C4Ph4) 1 . Compound 1 reacts with trimethylphosphine to produce Mo(PMe3)(η2‐C2Ph2)24‐C4Ph4) 2 , or reacts with diphenylacetylene to produce (η5‐C5Ph5)2Mo 3 and Mo(η2‐O2CPh)(η4‐C4Ph4H)(η4‐C4Ph4) 4 . The molecular structures of 1, 2 and 4 have been determined by an X‐ray diffraction study.  相似文献   

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