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1.
An improved synthetic method has been found for the preparation of the pentamethylcyclopentadienyl rhenium dicarbonyldihalide complexes. From the reaction of (η 5-C 5Me 5)Re(CO) 3 with Br 2 or I 2 in THF-H 2O a mixture of cis and trans isomers of (η 5-C 5Me 5)Re(CO) 2X 2 X = Br and I is formed. On the other hand, the reaction of [(η 5-C 5Me 5)Re(CO) 3C1][SbC1 6] in water gives the cis-(η 5-C 5Me 5)Re(CO) 2C1 2 complex. The solid IR spectra of the dicarbonyldihalide complexes are recorded and an assignment of the normal modes in terms of local symmetry is suggested by comparison with those observed in analogous molecules. A normal coordinate analysis performed using a modified general valence force field and considering simplified models, confirms most of the experimental assignments. The set of valence force constants reflects the structure of the isomers under study. 相似文献
2.
Irradiation of the 30-electron Mo 2(η 5-C 5Me 5) 2(CO) 4 and Re 2(CO) 10 in toluene solution (containing H 2O) afforded (in 1–2% yields) a novel triangular metal cluster, (η 5-C 5Me 5) 3Mo 3(CO) 4(η 2-H)(η 3-O) (1), which was characterized by a single-crystal X-ray diffraction study. Compound 1, of pseudo Cs- m symmetry, has a triangulo-Mo 3(η 3-O) core with composite Mo---H---Mo and Mo---Mo electron-pair bonds along one unusually short edge (2.660(1) Å) and Mo--- electron-pair bonds along the other two edges (2.916(1) and 2.917(1) Å). The edge-bridged hydride ligand, which displays a characteristic high-field proton NMR resonance at δ −17.79 ppm, was not found from the crystallographic determination but was located via a quantitative potential-energy-minimization method. This procedure unambiguously established that the optimized hydrogen position, which corresponds to a distinct coordination site with identical Mo---H distances of 1.85 Å, is the only one that can be sterically occupied by a metal-bound hydride ligand. This 46-electron species is the first electron-deficient trimolybdenum cluster containing a monoprotonated Mo---Mo double bond; its existence is attributed to ligand overcrowding due to the bulky pentamethylcyclopentadienyl rings. Black (η 5- C 5Me 5) 3Mo 3(CO) 4(η 2-H)(η 3-O) · 1/2THF crystallizes with two formula species in a triclinic unit cell of P1 symmetry with a 8.603(4), b 11.115(4), c 19.412(11) Å, 80.69(4)°, β 101.10(4)°, and γ 98.88(3)° at −40° C. Least-squares refinement (RAELS with 221 variables) of one independent Mo 3 molecule and a centrosymmetrically-disordered THF molecule converged at R1( F) 5.62%, R2( F 6.88% for 8460 independent diffractometry data ( I0 ρ 3σ( I0 collected at −40° C with Mo- K radiation 相似文献
3.
Cp 2MoH 2 reacts with methyl acrylate in the presence of acetylenes (L = C 2H 2, C 2Me 2, HCC tBu, HCCSiMe 3, C 2(SiMe 3) 2, HCCCH 2OMe, HCCCH 2NMe 2) to form acetylene complexes Cp 2Mo(L) 5. Protonation takes place with CF 3CO 2H at −80°C to give short-lived cations [Cp 2MoH(L) + (8) (L = C 2Me 2, HCCSiMe 3, C 2(SiMe 3) 2). The structure of [Cp 2MoH{η 2-C 2(SiMe 3) 2}]PF 6(9) was determined by an X-ray diffraction study. 相似文献
4.
(C 5Me 5) 2Sm(THF) 2 reacts with 1,2-epoxybutane in toluene to form, in addition to the toluene soluble [(C 5 Me 5) 2Sm] 2(μ-O), 1, the hexane soluble [(C 5Me 5) 2Sm(THF)] 2(μ-O), 2. In hexane, 2 loses THF to form 1 as a precipitate, but 1 cannot be converted to 2 by addition of THF at room temperature. Compound 1 does convert to 2 in low yield in THF at reflux. The reaction of (C 5Me 5) 2SM(phthalan) with 1,2-epoxybutane generates 1 and a phthalan analog of 2, [(C 5Me 5) 2Sm(phthalan)] 2(μ,-O), 3. Compound 2 reacts with Me 3CCN to form [(C 5Me 5) 2Sm(NCCMe 3)] 2(μ-O), 4, by displacement of THF. 相似文献
5.
The structures of the versatile starting compounds for organoiron complexes, the cationic aqua complex [(η 5-C 5Me 4Et)Fe(CO) 2(OH 2)]BF 4 (1b) and the halide complexes (η 5-C 5Me 5)Fe(CO) 2-I (2a), (η 5-C 5Me 4Et)Fe(CO) 2-I (2b) and (η 5-C 5Me 4Et)Fe(CO) 2-Cl (3b), are characterized by X-ray crystallography. Complex 1b [Fe---O: 2.022(8) Å and 2.043(9) Å, two independent molecules] is the first structurally characterized example of organoiron aqua complexes. Details of the synthetic procedures for the above complexes and the labile cationic THF complexes [η 5-C 5R 5)Fe(CO) 2(THF)]BF 4 (4) are disclosed, and the dissociation equilibrium of 4 is confirmed by means of variable temperature 1H-NMR as well as saturation transfer experiment. 相似文献
6.
The title compounds react with unidentate ligands, L, containing either phosphorus or arsenic donor atoms to yield the corresponding compounds of the type Ru(η 5---C 5Me 4Et)(CO)LX; with didentate phosphorus donor ligands the major species formed is the bridged complex {Ru(η 5---C 5Me 4Et)(CO)X} 2{Ph 2P(CH 2) nPPh 2} n = 1, X = Br; n = 2, X = Cl). In contrast, unidentate ligands containing nitrogen donor atoms such as pyridine did not react with Ru(η 5---C 5Me 4Et)(CO) 2Cl although reaction with 1,10-phenanthroline or diethylenetriamine yielded the ionic products [Ru(η 5---C 5Me 4Et)(CO)L] +Cl − (L = phen or (NH 2CH 2CH 2) 2NH). Reaction of Ru(η 5---C 5Me 4Et)(CO) 2Br with AgOAc yielded the corresponding acetato complex Ru(η 5---C 5Me 4Et)(CO) 20Ac. Ru(η 5--- C 5Me 4Et)(CO) 2X reacts with AgY (Y = BF 4 or PF 6) in either acetone or dichloromethane to give the useful solvent intermediates [Ru(η 5---C 5Me 4Et)(CO) 2(solvent)] +Y −, which readily react with ligands L to yield ionic derivatives of the type [Ru(η 5---C 5Me 4Et)(CO) 2L] +Y − (where L = CO, NCMe, py, C 2H 4 or MeO 2CCCCO 2Me). 相似文献
7.
A series of heterodimetallic complexes of general formula (C 5R 5)M(μ-CO) 3RuC 5Me 5 (M = Cr, Mo, W; R = Me, Et) has been prepared in good yields by the reaction of [C 5R 5M(CO) 3] − with [C 5Me 5Ru(CH 3CN) 3] +. (C 5Me 4Et)W(μ-CO) 3Ru(C 5Me 5) was characterized by a crystal structure determination. The W---Ru bond length of 2.41 Å is consistent with the formulation of a metal-metal triple bond, while the unsymmetrical bonding mode of the three bridging carbonyl groups reflects the inherent non-equivalence of the two different C 5R 5M-units. Using [CpRu(CH 3CN) 3] + or [CpRu(CO) 2(CH 3CN)] + as the cationic precursor leads to the formation of dimetallic species (C 5R 5)M(CO) 5RuC 5H 5 with both bridging and terminal carbonyl groups. 相似文献
8.
The singlet-triplet separations for the edge-sharing bioctahedral (ESBO) complex W 2(μ-H)(μ-Cl)(Cl 4(μ-dppm) 2 · (THF) 3 (II) has been studied by 31P NMR spectroscopy. The structural characterization of [W 2(μ-H) 2(μ-O 2CC 6H 5) 2Cl 2(P(C 6H 5) 3) 2] (I) by single-crystal X-ray crystallography has allowed the comparison of the energy of the HOMOLUMO separation determined using the Fenske-Hall method for a series of ESBO complexes with two hydride bridging atoms, two chloride bridging atoms and the mixed case with a chloride and hydride bridging atom. The complex representing the mixed case, [W 2(μ-H)(μ-Cl)Cl 4(μ-dppm) 2 · (THF) 3] (II), has been synthesized and the value of −2 J determined from variable-temperature 31P NMR spectroscopy. 相似文献
9.
Reaction of [Pt 2(η 5-C 5Me 5) 2(η-Br) 3] 3+(Br −) 3 with C 5R 5H (R = H,Me) in the presence of AgBF 4 gives the first platinocenium dications, [Pt(η 5-C 5Me 5)(η 5-C 5R 5)] 2+(BF 4− ) 2. On electrochemical reduction, [pt(η 5-C 5Me 5) 2] 2+ yields [Pt(η 4-C 5Me 5H)(η 2-C 5Me 5)]+ BF 4−. kw]Cyclopentadienyl; Metallocenes; Platinum; Electrochemistry 相似文献
10.
The reactions of the half-sandwich molybdenum(III) complexes CpMo(η 4-C 4H 4R 2)(CH 3) 2, where Cp=η 5-C 5H 5 and R=H or CH 3, with equimolar amounts of B(C 6F 5) 3 have been investigated in toluene. EPR monitoring shows the formation of an addition product which does not readily react with Lewis bases such as ethylene, pyridine, or PMe 3. The analysis of the EPR properties and the X-ray structure of a decomposition product obtained from dichloromethane, [CpMo(η 4-C 4H 6)(μ-Cl)(μ-CH 2)(O)MoCp][CH 3B(C 6F 5) 3], indicate that the borane attack has occurred at the methyl position. 相似文献
11.
A transition metal-substituted silylacetylene [(η 5-C 5H 5)Fe(CO) 2SiMe 2C] 2, [FpMe 2SiC] 2 (I) was synthesized and characterized spectroscopically and structurally. I crystallized in the monoclinic space group P2 1/ n, A = 13.011(3) Å B = 12.912(3) Å, C = 13.175(5) Å, β = 94.95(2). The acetylene linkage is reactive toward Co 2(CO) 8 to form I. Co 2(CO) 6 (II) which was also characterized spectroscopically and by single crystal X-ray diffraction. II crystallized in the orthorhombic space group Pbca, A = 17.64(2) Å, B = 14.225(10) Å, C = 24.49(2) Å. 相似文献
12.
139La-NMR chemical shifts were measured for several anionic complexes of formulae Li(C 4H 8O 2) 3/2 [La(ν 3-C 3H 5) 4], [Li(C 4H 8O 2) 2][Cp′ nLa(ν 3-C 3]H 5) 4−n] (Cp′ = Cp(ν 5-C 5H 5); n = 1, 2 and Cp′ = Cp * (ν 5-C 5Me5); N = 1) and Li[R nLa(ν 3-C 3H 4) 4− n] (R = N(SiMe 3) 2; n = 1, 2 and R = CCsIMe 3; n = 4), as well as for neutral compounds for formulae La(ν 3-C 3H 5) 3L n (L = (C 4H 8O 2) 1.5, (HMPT) 2, TMED), Cp′ nLa(ν 3-C 3H 5) 3−n (Cp′= Cp(ν 5-Cp 5H 5), Cp *(ν 5-C 5Me 5); n = 1, 2) and La(ν 3-C 3H 2) 2X(THF) 2 X = Cl, Br, I). Typical ranges of the 139La-NMR chemical shifts were found for the different types of complex independent of number and kind of organyl groups directly bonded to lanthanum. Zusammenfassung139La-NMR-Spektroskopie wurde an einer Reihe anionischer Allyllanthanat(III)-Komplexe der Zusammensetzung
]- [La)ν3-C3H5)4, [Li(C4H8)2][Cp′nLa(ν3-C3H5)4−n(Cp′ = Cp(ν5-C5H5); n = 1, 2 und Cp′ = Cp * (ν5-C5Me5); N = 1) und Li[RnLa(ν3-C3H5)4−n (R = B(SiMe3)2; n = 1, 2 und R = CCSiMe3; n = 4 sowie neutraler Allyllanthan(III)-Komplexe der Zusammensetzung La(ν3-C3H5)3Ln (Ln = (C4H8O2)1.5, (HMPT)2, TMED), Cp′n, La(ν3-C3H5)3−n (Cp′ = Cp(ν5-C5H5), Cp * (ν5- Cp5Me5); n = 1, 2) und La(ν3-Cp3H5)2X(THF)2 (X = Cl, Br, I) durchgefürt. In Abhängikeit von der Anzahl und der Art der am Lanthan gebundenen Gruppen wurden für die verschieden Komplextypen charakteristische Resonanzbereiche ermittelt. 相似文献
13.
The effects of cyclopentadienyl ring size on the geometry of bimetallic organosamarium complexes have been studied by comparing the X-ray crystal structure of [(C 5H 4Me) 2(THF)Sm(μ-Cl)] 2, prepared from KC 5H 4Me and SmCl 3 in THF, with C 5Me 5 analogs. The complex crystallizes from THF at −30°C in space group Pbcn with a = 20.312(5), b = 9.626(2), c = 16.225(3) Å, V = 3172.5(12) Å 3 and Dcalc = 1.74 g cm −3 for Z = 4. Least-squares refinement of the model based on 1759 reflections [| Fo| > 2.0σ(| Fo|)] converged to a final RF = 5.0%. The complex adopts a geometry which has a molecular two-fold rotation axis perpendicular to the Sm 2Cl 2 plane and a crystallographic inversion center. Hence, both methyl groups of each (C 5H 4Me) 2Sm unit are located on the side opposite of the THF ligands, which are trans to each other, and the four C 5H 4Me ring centroids define a square plane. The Sm---Cl distances are 2.759(3) and 2.819(3) Å. 相似文献
14.
Reaction of C 5H 4(SiMe 3) 2 with Mo(CO) 6 yielded [(η 5-C 5H 3(SiMe 3) 2)Mo(CO) 3] 2, which on addition of iodine gave [(η 5-C 5H 3(SiMe 3) 2Mo(CO) 3I]. Carbonyl displacement by a range of ligands: [L = P(OMe) 3, P(OPr i) 3,P(O- o-tol) 3, PMe 3, PMe 2Ph, PMePh 2, PPh 3, P( m-tol) 3] gave the new complexes [(η 5-C 5H 3(SiMe 3) 2 MO(CO) 2(L)I]. For all the trans isomer was the dominant, if not exclusive, isomer formed in the reaction. An NOE spectral analysis of [(η 5-C 5H 3(SiMe 3) 2)Mo(CO) 2(L)I] L = PMe 2Ph, P(OMe) 3] revealed that the L group resided on the sterically uncongested side of the cyclopentadienyl ligand and that the ligand did not access the congested side of the molecule. Quantification of this phenomenon [L = P(OMe) 3] was achieved by means of the vertex angle of overlap methodology. This methodology revealed a steric preference with the trans isomer (less congestion of CO than I with an SiMe 3 group) being the more stable isomer for L = P(OMe) 3. 相似文献
15.
The dimethylphosphino substituted cyclopentadienyl precursor compounds [M(C 5Me 4CH 2PMe 2)], where M=Li + (1), Na + (2), or K + (3), and [Li(C 5H 4CR′ 2PMe 2)], where R′ 2=Me 2 (4), or (CH 2) 5 (5), [HC 5Me 4CH 2PMe 2H]X, where X −=Cl − (6) or PF 6− (7) and [HC 5Me 4CH 2PMe 2] (8), are described. They have been used to prepare new metallocene compounds, of which representative examples are [Fe(η-C 5R 4CR′ 2PMe 2) 2], where R=Me, R′=H (9); R=H and R′ 2=Me 2 (10), or (CH 2) 5 (11), [Fe(η-C 5H 4CMe 2PMe 3) 2]I 2 (12), [Fe{η-C 5Me 4CH 2P(O)Me 2} 2] (13), [Zr(η-C 5R 4CR′ 2PMe 2) 2Cl 2], where R=H, R′=Me (14), or R=Me, R′=H (15), [Hf(η-C 5H 4CMe 2PMe 2) 2]Cl 2] (16), [Zr(η-C 5H 4CMe 2PMe 2) 2Me 2] (17), {[Zr(η-C 5Me 4CH 2PMe 2) 2]Cl}{(C 6F 5) 3BClB(C 6F 5) 3} (18), [Zr{(η-C 5Me 4CH 2PMe 2) 2Cl 2}PtI 2] (19), [Mn(η-C 5Me 4CH 2PMe 2) 2] (20), [Mn{(η-C 5Me 4CH 2PMe 2B(C 6F 5) 3} 2] (21), [Pb(η-C 5H 4CMe 2PMe 2) 2] (23), [Sn(η-C 5H 4CMe 2PMe 2) 2] (24), [Pb{η-C 5H 4CMe 2PMe 2B(C 6F 5) 3} 2] (25), [Pb(η-C 5H 4CMe 2PMe 2) 2PtI 2] (26), [Rh(η-C 5Me 4CH 2PMe 2)(C 2H 4)] 29, [M(η,κ P-C 5Me 4CH 2PMe 2)I 2], where M=Rh (30), or Ir, (31). 相似文献
16.
The complex [MoW(μ-CC 6H 4Me-4)(CO) 2(η 7-C 7H 7)(η 5-C 2B 9H 10Me)] reacts with diazomethane in Et 2O containing EtOH to afford the dimetal compound [MoW(OEt)(μ-CH 2){μ-C(C 6H 4Me-4)C(Me)O}(η 7-C 7H 7)(η 5-C 2B 9H 10Me)]. The structure of this product was established by X-ray diffraction. The Mo---W bond [2.778(4) Å] is bridged by a CH 2 group [μ-C---Mo 2.14(3), μ-C---W 2.02(3) Å] and by a C(C 6H 4Me-4)C(Me)O fragment [Mo---O 2.11(3), W---O 2.18(2), Mo---C(C 6H 4Me-4) 2.41(3), W---C(C 6H 4Me-4) 2.09(3), Mo---C(Me) 2.26(3) Å]. The molybdenum atom is η 7-coordinated by the C 7H 7 ring and the tungsten atom is η 5-coordinated by the open pentagonal face of the nido-icosahedral C 2B 9H 10Me cage. The tungsten atom also carries a terminally bound OEt group [W---O 1.88(3) Å]. The 1H and 13C-{ 1H} NMR data for the dimetal compound are reported and discussed. 相似文献
17.
The reaction of the anionic mononuclear rhodium complex [Rh(C 6F 5) 3Cl(Hpz)] t- (Hpz = pyrazole, C 3H 4N 2) with methoxo or acetylacetonate complexes of Rh or Ir led to the heterodinuclear anionic compounds [(C 6F 5) 3Rh(μ-Cl)(μ-pz)M(L 2)] [M = Rh, L 2 = cyclo-octa-1,5-diene, COD (1), tetrafluorobenzobarrelene, TFB (2) or (CO) 2 (4); M = Ir, L 2 = COD (3)]. The complex [Rh(C 6F 5) 3(Hbim)] − (5) has been prepared by treating [Rh(C 6F 5) 3(acac)] − with H 2bim (acac = acetylacetonate; H 2bim = 2,2′-biimidazole). Complex 5 also reacts with Rh or Ir methoxo, or with Pd acetylacetonate, complexes affording the heterodinuclear complexes [(C 6F 5) 3Rh(μ-bim)M(L 2)] − [M = Rh, L 2 = COD (6) or TFB (7); M = Ir, L 2 = COD (8); M = Pd, L 2 = η 3-C 3H 5 (9)]. With [Rh(acac)(CO) 2], complex 5 yields the tetranuclear complex [{(C 6F 5) 3Rh(μ-bim)Rh(CO) 2} 2] 2−. Homodinuclear Rh III derivatives [{Rh(C 6F 5) 3} 2(μ-L) 2] ·- [L 2 = OH, pz (11); OH, S tBu (12); OH, SPh (13); bim (14)] have been obtained by substitution of one or both hydroxo groups of the dianion [{Rh(C 6F 5) 3(μ-OH)} 2] 2− by the corresponding ligands. The reaction of [Rh(C 6F 5) 3(Et 2O) x] with [PdX 2(COD)] produces neutral heterodinuclear compounds [(C 6F 5) 3Rh(μ-X) 2Pd(COD)] [X = Cl (15); Br (16)]. The anionic complexes 1–14 have been isolated as the benzyltriphenylphosphonium (PBzPh 3+) salts. 相似文献
18.
Thermal displacement of coordinated nitriles RCN (R = CH 3, C 2H 5 or n-C 3H 7) in [C 5H 5Fe(L 2)(NCR)]X complexes (L 2 = P(OCH 3) 3) 2, (P(OC 6H 5) 3) 2 or (C 6H 5) 2PC 2H 4P(C 6H 5) 2 (DPPE)) by E(CH 3) 2 affords high yields of [C 5H 5Fe(L 2)(E(CH 3) 2)]X compounds (E = S, Se and Te; X = BF 4 or PF 6). Spectroscopic data and ligand displacement reactions are presented and discussed together with related observations on [C 5H 5Fe(CO) 2(E(CH 3) 2)]BF 4 compounds. The molecular structure of [C 5H 5Fe(P(OCH 3) 3) 2(S(CH 3) 2)]PF 6 was determined by a single-crystal X-ray diffraction study: monoclinic, space group P2 1/ n- C52h (No. 14) with a = 8.4064(12), b = 11.183(2), c = 50.726(8) Å, β = 90.672(13)° and Z = 8 molecules per unit cell. The coordination sphere of the iron atom is pseudo-tetrahedral with an Fe---S bond distance of 2.238 Å. 相似文献
19.
The methylene-bridged, mixed-chalogen compounds Fe 2(CO) 6(μ-SeCH 2Te) (1) and Fe 2(CO) 6(μ-SCH 2Te) (3) have been synthesised from the room temperature reaction of diazomethane with Fe 2(CO) 6(μ-SeTe) and Fe 2(CO) 6(μ-STe), respectively. Compounds 1 and 3 have been characterised by IR, 1H, 13C, 77Se and 125Te NMR spectroscopy. The structure of 1 has been elucidated by X-ray crystallography. The crystalsare monoclinic,space group P2 1/ n, A = 6.695(2), B = 13.993(5), C = 14.007(4)Å, β = 103.03(2)°, V = 1278(7) Å 3, Z = 4, Dc = 2.599 g cm −3 and R = 0.030 ( Rw = 0.047). 相似文献
20.
Reactions of the lithium salts of 3-substituted indenes 1, 2 with ZrCl 4(THF) 2 gave two series of nonbridged bis(1-substituted)indenyl zirconocene dichloride complexes. Fractional recrystallization from THF–petroleum ether furnished the pure racemic and mesomeric isomers of [(η 5-C 9H 6-1-C(R 1)(R 2)--- o-C 6H 4---OCH 3) 2ZrCl 2]· nTHF (R 1=R 2=CH 3, n=1, rac-1a and meso-1b; R 1=CH 3, R 2=C 2H 5; n=0.5 or 0, rac-2a and meso-2b), respectively. Complex 1a was further characterized by X-ray diffraction to have a C2 symmetrically racemic structure, where the six-member rings of the indenyl parts are oriented laterally and two o-CH 3O---C 6H 4---C(CH 3) 2--- substituents are oriented to the open side of the metallocene (Ind: bis-lateral, anti; Substituent: bis-central, syn). The four zirconocene complexes are highly symmetrical in solution as characterized by room temperature 1H-NMR, however 1H– 1H NOESY of meso-1b shows that some of the NOE interactions arise from the two separated indenyl parts of the same molecule, which can only be well explained by taking into account the torsion isomers in solution. 相似文献
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