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1.
The reaction between Ru3(CO)12 and a cyclic olefin (cis-cyclooctene or trans-cyclododecene) at 100 °C for several hours gives the title compounds (μ-H)2RU3(CO)932-C8H12) (1), and (μ-H)RU3(CO)933-C12H19) (2), both of which have been characterized by X-ray diffraction studies, IR and NMR spectral measurements and elemental analysis. The prolonged reaction between Ru3(CO)12 and cis-cyclooctene gives compound HRu3(CO)9(C8H11) (3). Compound 3 has been characterized with IR and NMR spectral analyses. In 1 the cyclooctene ring is linked via a μ32-alkyne type of bonding to the face of the Ru3 cluster. It is formally σ-bonded to two of the three Ru atoms and π-bonded to the third Ru. The two hydrides in 1 are bridging Ru---Ru bonds. In 2 the cyclododecene ring is bonded to the Ru3 face via the μ33-CCHC linkage. There are two formal σ-bonds from the allyl part to the hydrido-bridged Ru atoms and the η3-allyl linkage to the third Ru atom.  相似文献   

2.
Irradiation of the 30-electron Mo25-C5Me5)2(CO)4 and Re2(CO)10 in toluene solution (containing H2O) afforded (in 1–2% yields) a novel triangular metal cluster, (η5-C5Me5)3Mo3(CO)42-H)(η3-O) (1), which was characterized by a single-crystal X-ray diffraction study. Compound 1, of pseudo Cs-m symmetry, has a triangulo-Mo33-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 (η5- C5Me5)3Mo3(CO)42-H)(η3-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 Mo3 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.
The coordinatively unsaturated cluster [Pt33-CO)(μ-dppm)3]2+ (1, dppm = Ph2PCH2PPh2) reacts with Na+[M(CO)5] to give the mixed metal clusters [Pt3{M(CO)3}(μ-dppm)3]+ (M = Re, 2; Mn, 3). The new clusters are characterized by spectroscopic methods and, for M = Re, by an X-ray structure determination. The Pt3Re core in 2 is tetrahedral with particularly short metal-metal distances.  相似文献   

4.
The compound [RU332- -ampy)(μ3η12-PhC=CHPh)(CO)6(PPh3)2] (1) (ampy = 2-amino-6-methylpyridinate) has been prepared by reaction of [RU3(η-H)(μ32- ampy) (μ,η12-PhC=CHPh)(CO)7(PPh3)] with triphenylphosphine at room temperature. However, the reaction of [RU3(μ-H)(μ3, η2 -ampy)(CO)7(PPh3)2] with diphenylacetylene requires a higher temperature (110°C) and does not give complex 1 but the phenyl derivative [RU332-ampy)(μ,η 12 -PhC=CHPh)(μ,-PPh2)(Ph)(CO)5(PPh3)] (2). The thermolysis of complex 1 (110°C) also gives complex 2 quantitatively. Both 1 and 2 have been characterized by0 X-ray diffraction methods. Complex 1 is a catalyst precursor for the homogeneous hydrogenation of diphenylacetylene to a mixture of cis- and trans -stilbene under mild conditions (80°C, 1 atm. of H2), although progressive deactivation of the catalytic species is observed. The dihydride [RU3(μ-H)232-ampy)(μ,η12- PhC=CHPh)(CO)5(PPh3)2] (3), which has been characterized spectroscopically, is an intermediate in the catalytic hydrogenation reaction.  相似文献   

5.
Structures of non metal-metal bonded phosphido-bridged heterobimetallic complexes, including CpFe(CO)2(μ-PPh2)W(CO)5 (1-W) and metal-metal bonded CpFe(CO)(μ-CO)(μ-PPh2)W(CO)4 (2), were determined by a single crystal X-ray diffraction study. In 1-W, the long distance between Fe and W indicates no metal-metal bond to exist. In 2, a Fe---W bond with bond length 2.851 Å and a semibridging carbonyl with W---C---O angle 153° were observed. Mössbauer spectra of 1-W and 2 were taken at 77 K. Isomer shifts of 1-W and 2 were − 0.0203 mm s−1 and 0. 1917 mm s−1 respectively.  相似文献   

6.
The singlet-triplet separations for the edge-sharing bioctahedral (ESBO) complex W2(μ-H)(μ-Cl)(Cl4(μ-dppm)2 · (THF)3 (II) has been studied by 31P NMR spectroscopy. The structural characterization of [W2(μ-H)2(μ-O2CC6H5)2Cl2(P(C6H5)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, [W2(μ-H)(μ-Cl)Cl4(μ-dppm)2 · (THF)3] (II), has been synthesized and the value of −2J determined from variable-temperature 31P NMR spectroscopy.  相似文献   

7.
The methylene-bridged, mixed-chalogen compounds Fe2(CO)6(μ-SeCH2Te) (1) and Fe2(CO)6(μ-SCH2Te) (3) have been synthesised from the room temperature reaction of diazomethane with Fe2(CO)6(μ-SeTe) and Fe2(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 P21/n, A = 6.695(2), B = 13.993(5), C = 14.007(4)Å, β = 103.03(2)°, V = 1278(7) Å3, Z = 4, Dc = 2.599 g cm−3 and R = 0.030 (Rw = 0.047).  相似文献   

8.
9.
The title complex Mn2(CO)6(μ-H){μ-S(SC3H5)C=C(PPr3i)S} was synthesized by allyation of the homobinuclear anion [Mn2(CO)6(μ-H){μ-S(SC3H5)C=C(PPr3i)S}]−1, and characterized by elemental analysis, IR, 1H NMR and 31P NMR spectra. The molecular structure shows that it contains a novel fairly planar ligand S(S)C=C(PPr3i)S, and the two Mn(CO)3 fragments are symmetrically placed at both sides of the plane of the ligand.  相似文献   

10.
Novel isonitrile derivatives of a diruthenium carbonyl complex, (μ235-guaiazulene)Ru2(CO)5 (2), were synthesized by substitution of a CO ligand by an isonitrile, and were subjected to studies on thermal and photochemical haptotropic interconversion. Treatment of 2 (a 45:55 mixture of two haptotropic isomers, 2-A and 2-B) with RNC at room temperature resulted in coordination of RNC and alternation of the coordination mode of the guaiazulene ligand to form (μ215-guaiazulene)Ru2(CO)5(CNR), 5d–5f, [5d; R=tBu, 5e; 2,4,6-Me3C6H2, or 5f; 2,6-iPr2C6H3] in moderate to good yields. Thermal dissociation of a CO ligand from 5 at 60 °C resulted in quantitative formation of a desirable isonitrile analogue of 2, (μ235-guaiazulene)Ru2(CO)4(CNR), 4d–4f, [4d; R=tBu, 4e; 2,4,6-Me3C6H2, or 4f; 2,6-iPr2C6H3], as a 1:1 mixture of the two haptotropic isomers. A direct synthetic route from 2 to 4d–4f was alternatively discovered; treatment of 2 with one equivalent of RNC at 60 °C gave 4d–4f in moderate yields. All of the new compounds were characterized by spectroscopy, and structures of 5d (R=tBu) and 4d-A (R=tBu) were determined by crystallography. Thermal and photochemical interconversion between the two haptotropic isomers of 4d–4f revealed that the isomer ratios in the thermal equilibrium and in the photostatic state were in the range of 48:52–54:46.  相似文献   

11.
The cationic diphenylphosphido-bridged compound [Ru2(μ-PPh2)(μ-OH)26-p-cymene)2][PF6) (2) has been prepared by reaction of the tri-μ-hydroxo complex [Ru2(μ-OH)3(η-p-cymene)2][PF6] (1) with diphenylphosphine. Complex 2 eliminates water on reaction with protic acids, incorporating the conjugate base of the added acid as a bridging ligand. Formic acid, acetic acid, phenol, and aniline react with 2 to give the monosubstituted compounds [Ru2(μ-PPh2)(μ-OH)(μ-L)(η6-p-cymene)2]PF6] (L = HCO2, MeCO2, OPh, or NHPH), whereas methanol, thiophenol, 1,2-benzenedithiol, hydrochloric acid and isopropanol afford the disubstituted derivatives [Ru2(μ-PPh2)(μ-L)26-p-cymene)2]PF6] (L = OMe, SPh, S2C6H4, Cl, or H).  相似文献   

12.
The product isolated from the reaction of (μ-H)2Os3(CO)9(PPh3) with ethylene is shown to be the ethylidene complex (μ-H)2Os3(CO)9(PPh3)(μ-CHCH3) (1) rather than the ethylene complex (μ-H)(H)Os3(CO)9(PPh3)(C2H4), as previously claimed. The characterization of 1 is based on a combination of 1H and 13C NMR results. The 1H NMR data (δ 6.84 (1 HD), 2.53 (3 HC), J(CD) = 7.4 Hz) establish the presence of the ethylidene moiety, whereas detailed analysis of the 1-D and 2-D 13C NMR spectra of 13CO-enriched 1 indicates the relative positions of the ethylidene, hydride, and phosphine ligands on the triosmium framework.  相似文献   

13.
The reaction between metallic barium and fluoroisopropanol or alcoholysis of [Ba(OPri)2] produces a pentanuclear fluoroalkoxide. Its X-ray structure determination showed its formulation to correspond to Ba55-OH)[μ3-OCH(CF3)2]42-OCH(CF3)2]4 [OCH(CF3)2](THF)4(H2O)·THF. The metallic core is based on a square pyramid encapsulating an hydroxo ligand. In addition to the barium---alkoxide bonds [2.53(3)–2.86(3) Å] neutral O-donors, four THF [2.82(2)–2.86(3) Å] and one H2O [2.79(3) Å] and secondary barium---fluorine interactions [2.99(2)–3.31(2) Å] ensure high coordination numbers, from 9 to 11 for the metal centers. Hydrogen bonding between the apical fluoroisopropoxide, the water molecule and one THF molecule, non-bonded to a metal center, accounts for the stability of the hydrate and illustrates the Lewis acidity of fluoroalkoxides. Thermal decomposition leads to BaF2.  相似文献   

14.
The reactions of the diruthenium carbonyl complexes [Ru2(μ-dppm)2(CO)4(μ,η2-O2CMe)]X (X=BF4 (1a) or PF6 (1b)) with neutral or anionic bidentate ligands (L,L) afford a series of the diruthenium bridging carbonyl complexes [Ru2(μ-dppm)2(μ-CO)22-(L,L))2]Xn ((L,L)=acetate (O2CMe), 2,2′-bipyridine (bpy), acetylacetonate (acac), 8-quinolinolate (quin); n=0, 1, 2). Apparently with coordination of the bidentate ligands, the bound acetate ligand of [Ru2(μ-dppm)2(CO)4(μ,η2-O2CMe)]+ either migrates within the same complex or into a different one, or is simply replaced. The reaction of [Ru2(μ-dppm)2(CO)4(μ,η2-O2CMe)]+ (1) with 2,2′-bipyridine produces [Ru2(μ-dppm)2(μ-CO)22-O2CMe)2] (2), [Ru2(μ-dppm)2(μ-CO)22-O2CMe)(η2-bpy)]+ (3), and [Ru2(μ-dppm)2(μ-CO)22-bpy)2]2+ (4). Alternatively compound 2 can be prepared from the reaction of 1a with MeCO2H–Et3N, while compound 4 can be obtained from the reaction of 3 with bpy. The reaction of 1b with acetylacetone–Et3N produces [Ru2(μ-dppm)2(μ-CO)22-O2CMe)(η2-acac)] (5) and [Ru2(μ-dppm)2(μ-CO)22-acac)2] (6). Compound 2 can also react with acetylacetone–Et3N to produce 6. Surprisingly [Ru2(μ-dppm)2(μ-CO)22-quin)2] (7) was obtained stereospecifically as the only one product from the reaction of 1b with 8-quinolinol–Et3N. The structure of 7 has been established by X-ray crystallography and found to adopt a cis geometry. Further, the stereospecific reaction is probably caused by the second-sphere π–π face-to-face stacking interactions between the phenyl rings of dppm and the electron-deficient six-membered ring moiety of the bound quinolinate (i.e. the N-included six-membered ring) in 7. The presence of such interactions is indeed supported by an observed charge-transfer band in a UV–vis spectrum.  相似文献   

15.
Reaction of the activated mixture of Re2(CO)10, Me3NO and MeOH with a 1:1 mixture of rac (d/l)- and meso-1,1,4,7,10,10-hexaphenyl-1,4,7,10-tetraphosphadecane (hptpd) yields a mixture of (d/l)- and meso-[{Re2(μ-OMe)2(CO)6}2(μ,μ′-hptpd)] 1. The diastereomers can be easily separated by selective dissolution of d/l-1 in benzene, and give clearly distinguishable 1H- and 31P-NMR spectra. The fluxional behavior of d/l-1 in solution has been studied by variable-temperature 1H- and 31P-{1H}-NMR spectroscopy. The crystal structures of both d/l- and meso-1 have been determined. Both molecules consist of two {Re2(μ-OMe)2(CO)6} moieties which are bridged by the two P---CH2---CH2---P moieties of the hptpd ligand. Whilst the molecules of meso-1 possess crystallographic i-symmetry, those of d/l-1 do not have any crystallographic symmetry. These diastereomers therefore give clearly distinguishable Raman spectra in the solid state. Reaction of tris[2-(diphenylphosphino)ethyl]phosphine (tdppep) with the activated mixture affords the complex [{Re2(μ-OMe)2(CO)6}(μ,η2-tdppep)] 2, and the analogous reaction involving bis[2-diphenylphospinoethyl)phenylphosphine (triphos) gives [{Re2(μ-OMe)2(CO)6}(μ,μ′,η3-triphos){Re2(CO)9}] 3 and [{Re2(μ-OMe)2(CO)6}(μ,η2-triphos)] 4.  相似文献   

16.
The interaction between Mo2(O2CCH3)4, Me3SiI and I2 in THF resulted in oxygen abstraction from the solvent and formation of [Mo2(μ-O)(μ-I)(μ-O2CCH3) I2(THF)4]+[MoOI4(THF)] and I---(CH2)4---I. The molybdenum complex has been characterized by X-ray diffractometry. Crystal data: triclinic, space group P , a = 13.827(3) Å; b = 15.803(7) Å; c = 9.950(3) Å; = 93.34(4)°; β = 102.40(2)°; γ = 90.09(2)°; V = 2120(2) Å3; Z = 2; dcalc = 2.559 g cm−3; R = 0.0476 (Rw = 0.0613) for 370 parameters and 3938 data with F02> 3σ(F02). The metal-metal distance in the cation is 2.527(2) Å and indicates a strong interaction. The magnetic behavior is consistent with the assignment of one unpaired electron to the Mo27+ core of the cation and one to the d1 Mo(V) center of the anion. The interaction between Mo(CO)6 and I2 in THF also results in the formation of 1,4-diiodobutane.  相似文献   

17.
Peter C. Junk  Jonathan W. Steed   《Polyhedron》1999,18(27):4646-3597
[Co(η2-CO3)(NH3)4](NO3)·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O were prepared by prolonged aerial oxidation of a solution of Co(NO3)2·6H2O and ammonium carbonate in aqueous ammonia. The formation of these side products highlights the richness of the chemistry of these systems and the possibility of by products if methods are not strictly adhered to. The X-ray crystal structures of [Co(η2-CO3)(NH3)4][NO3]·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O reveal a monomeric octahedral cobalt center with η2-bound CO32− in the former, while the latter consists of a dimeric array where the two cobalt centers are bridged by two OH and one μ2-CO32− groups with three terminal NH3 ligands for each Co center. In both complexes extensive hydrogen bonding interactions are evident.  相似文献   

18.
The reaction of [(CO)PPh3)2Re(μ-H)2(μ-NCHPh)Ru(PPh3)2(PhCN)] (2) with HBF4-Me2O generates [(CO)PPh3)2Re(μ- H)2(μ,η12HNCHPh)Ru(PPh3)2(PhCN)][BF4] (3). Monitoring the reaction by NMR spectroscopy shows the intermediate formation of [(CO)(PPh3)2 HRe(μ-H)2(μ-NCHPh)Ru(PPh3)2(PhCN)][BF4] (4). Attempted reduction of the imine ligand by a nucleophile (H or CN) failed, regenerating 2. Under dihydrogen at 50 atm, 3 is slowly transformed into [(CO)(PPh3)2HRe(μ-H)3Ru(PPh3)2(PhCN)][BF4] (5) with liberation of benzyl amine.  相似文献   

19.
The ionic coupling of [Os4H2(CO)12]2− with [Ru(η6-C6H6)(MeCN)3]2+ affords the neutral mixed metal cluster Os4Ru(μH)2(CO)12(η6-C6H6) 1. The reaction of 1 with trimethylphosphite leads to the initial formation of the addition product Os4Ru(μH)2(CO)12(η6-C6H6)P(OMe)3 2, but this complex rearranges in solution to give Os4Ru(μ-H)3(CO)12(μ3-η6-C6H5)P(OMe)3 3. An X-ray structure of 3 shows that the metal core of the cluster is a ruthenium-spiked Os4 tetrahedron, with one hydrogen atom from the arene having transferred to the Os4 core, and one arene carbon bridging an Os-Os edge, while the ring as a whole remains η6-bound to the Ru atom.  相似文献   

20.
Treatment of ruthenium complexes [CpRu(AN)3][PF6] (1a) (AN=acetonitrile) with iron complexes CpFe(CO)2X (2a–2c) (X=Cl, Br, I) and CpFe(CO)L′X (6a–6g) (L′=PMe3, PMe2Ph, PMePh2, PPh3, P(OPh)3; X=Cl, Br, I) in refluxing CH2Cl2 for 3 h results in a triple ligand transfer reaction from iron to ruthenium to give stable ruthenium complexes CpRu(CO)2X (3a–3c) (X=Cl, Br, I) and CpRu(CO)L′X (7a–7g) (L′=PMe3, PMe2Ph, PMePh2, PPh3, P(OPh)3; X=Br, I), respectively. Similar reaction of [CpRu(L)(AN)2][PF6] (1b: L=CO, 1c: P(OMe)3) causes double ligand transfer to yield complexes 3a–3c and 7a–7h. Halide on iron, CO on iron or ruthenium, and two acetonitrile ligands on ruthenium are essential for the present ligand transfer reaction. The dinuclear ruthenium complex 11a [CpRu(CO)(μ-I)]2 was isolated from the reaction of 1a with 6a at 0°C. Complex 11a slowly decomposes in CH2Cl2 at room temperature to give 3a, and transforms into 7a by the reaction with PMe3.  相似文献   

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