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1.
A study has been carried out of the catalytic activity of the systems formed by [HRh{P(OPh)3}4] or [HRh(CO){P(OPh)3}3] with the modifying ligands P(OPh)3, PPh3, diphos and Cp2Zr(CH2PPh2)2 in hydroformylation of hex-1-ene (at p = 5 bar). The best results were obtained with the system [HRh{P(OPh)3}4]+Cp2Zr(CH2PPh2)2 (75–85% yeild of aldehydes).  相似文献   

2.
The compounds Cp2VR (R = CH3, C2H5, n-C3H7, n-C4H9, n-C5H11, CH2C(CH3)3 or CH2Si(CH3)3) have been prepared from Cp2 VCl and RMgX in n-pentane. The air-sensitive compounds are stable at room temperature, but decompose between 65 and 138°C. The thermal stability decreases in the order R = CH3 CH2Si(CH3)3 > C2H5 > CH2C(CH3)3 > n-C5H11 > n-C4H9 > n-C3H7. Compounds with R = i-C3H7 or t-C4H9 could not be obtained.  相似文献   

3.
Synthesis of H3Ru33-CSEt)(CO)9, is accomplished by base-promoted attack of ethanethiol on H3Ru33-CBr)(CO)9. Thermolysis of this product under CO yields HRu3(CH2SEt)(CO)9. Reactions of H3Ru33-CSEt)(CO)9 with alkynes C2R2 form HRu333-EtSCCRCR)(CO)9 (R = Me or Ph) and Ru3 (cis-CR=CHR)(CSEt)(CO)9 (R = Me). The chemistry of H3Ru33-CSEt)(CO)9 differs significantly from that of the analogous ether derivative H3Ru33-COMe)(CO)9.  相似文献   

4.
Six new cluster derivatives [Rh2Co2(CO)6(μ-CO)442-HCCR)] (R=FeCp2 1, CH2OH 2, (CH3O)C10H6CH(CH3)COOCH2CCH 3) and [RhCo3(CO)6(μ-CO)442-HCCR)] (R=FeCp2 4, CH2OH 5, (CH3O)C10H6CH(CH3)COOCH2CCH 6) were obtained by the reactions of [Rh2Co2(CO)12] and [RhCo3(CO)12] with substituted 1-alkyne ligands HCCR [R=FeCp2 7, CH2OH 8, (CH3O)C10H6CH(CH3) COOCH2CCH 9] in n-hexane at room temperature, respectively. Alkynes insert into the Co---Co bond of the tetranuclear clusters to give butterfly clusters. [Rh2Co2(CO)6(μ-CO)442-HCCFeCp2)] (1) was characterized by a single-crystal X-ray diffraction analysis. Reactions of 1, 2 with 7, 8 and ambient pressure of carbon monoxide at 25 °C gave two known cluster complexes [Co2(CO)62, η2-HCCR)] (R=FeCp2 10, CH2OH 11), respectively. All clusters were characterized by element analysis, IR and 1H-NMR spectroscopy.  相似文献   

5.
Hydrogensulfido and hydrogenselenido complexes of general composition (η5-C5R5(CO)3M(EH) (R = H, CH3; M = Cr, Mo, W; E = S, Se) react at the EH functions by deprotonation, bimolecular elimination of H2E, or by loss of the chalcogen atoms E. Reactions with Lewis-acidic complex cations such as [((η5-C5R5)(CO)3M]+ (R = H, CH3; M = Mo, W) are useful for the synthesis of chalcogen bridged compounds (μ-E)[(η5-C5R5)(CO)3M]2. The heterodinuclear chalcogen bridge complexes thus generated form metathesis equilibria with their corresponding homodinuclear systems.  相似文献   

6.
Hydrogenchalcogenido complexes of general composition (η5-C5R5)(CO)3M(EH) (R = H, CH3; M = Cr, Mo, W; E = S, Se) can be obtained by three different routes, sometimes in quite good yields. Thus, the sulfur and selenium derivatives can be synthesized by insertion of the respective elements into the metal-hydrogen bonds of the precursor compounds (η5-C5R5)(CO)3MH. This species also reacts with potassium selenocyanate to yield the hydrogenselenido derivatives (η5-C5R5)(CO)3M(SeH) which can also be obtained by treatment of the methyl complexes (η5-C5R5)(CO)3M(CH3 (M = Mo, W) with HBF4 and Li[SeH]. The corresponding hydrogentellurido compounds are probably formed by these preparative methods but appear to be quickly converted into either the dinuclear tellurium bridge products (μ-Te)[(η5-C5R5)(CO)3M]2 (M = Mo) or into the hydrido complexes (η5-C5R5)(CO)3MH (M= Mo, W) by release of elemental tellurium.  相似文献   

7.
Reaction of [Cp*TiF3] (Cp* = (ν5-C5Me5)) with Me3SiOSO2- p-C6H4CH3, Me3SiOPOPh2 and 1,2-(Me3SiOCO)2C6H4 yields the dinuclear complexes [{Cp*TiF(μ-F)(μ-OSO2-p-C6H4CH4)}2] (1), [{Cp*TiF(μ-F)(μ-OPOPh2)}2] (2) and [{Cp*TiF(μ-F)(μ-OCO-o-C6H4CO2SiMe3)}2] (3). The molecular structures of 1 and 2 have been determined by single-crystal X-ray analysis. In complexes 1-3, the two titanium atoms are connected by bridging fluorine atoms as well as bridging sulfonate, phosphinate and carboxylate groups respectively. Each titanium atom is also bonded to a terminal fluorine atom. Reaction of [Cp2*ZrF2] with 1,2-(Me3SiOCO)2C6H4 leads to the mononuclear pentacoordinate 18-electron species [Cp2*ZrF(μ-OCO-o-C6H4CO2SiMe3)] (4) and its structure was determined by X-ray crystallographic methods.  相似文献   

8.
While each of the three organosamarium(III) title complexes: [Cp2Sm{μ-OC10H19}]2 (5; Cp = C5H5, OC10H19 = isomenthoxide), [Cp2Sm{μ-OCH(Me)COOiBU}]2 (6) and [Cp3SmOS(Me)-p-C6H4Me] (7) contains a chiral ligand atom (i.e. C or S) next to the metal-bonded oxygen atoms, only the dinuclear compounds 5 and, even better, 6 display (below ca. 600 nm) significant circular dichroism of discrete f---f-crystal field transitions. According to a successful single-crystal X-ray study of 5, the cyclohexyl ring of its (1S,2R,5R)-isomenthoxide ligand adopts a conformation with axial OSm- and iPr-substituents, which is energetically less favourable at least for neat (1S,2R,5R)-isomenthol.

Zusammenfassung

Obwohl jeder der drei neuen Organosamarium(III)-Komplexe: [Cp2Sm{μ-OC10OH19}]2 (5; Cp = C5H5, OC10H19 = Isomentholat), [Cp2Sm{μ-OCH(Me)COOiBU}]2 (6) und [Cp3SmOS(Me)-p-C6H4Me] mindestens ein chirales Ligandenatom (C oder S) unmittelbar am metallkoordinierten O-Atom enthält, zeigen nur die dimeren Systeme 5 und noch ausgeprägter 6 (unterhalb von ca. 600 nm) signifikanten Circulardichroismus von f---f-Kristallfeldübergängen des Sm3+-Ions. Auf Grund einer erfolgreichen Kristallstrukturanalyse von 5 liegt der Cyclohexylring des (1S,2R,5R)-Isomentholatliganden ausschließlich in der Konformation mit axialen OSm- und iPr-Substituenten vor, die für freies (1S,2R,5R)-Isomenthol energetisch deutlich unvorteilhafter ist.  相似文献   


9.
The reaction of [Cp2MoH2] and AgBF4 with the dithio ligands Na(S2CPh) and K(S2COiPr) afforded the complexes [(Cp2MoH2AgS2CPh)2] (1) and [(Cp2MoH2AgS2COiPr)2] (2). Using the monothio ligands Na(SC(O)Ph), K(SC(O)CH3) and Na(S(NHPh)C=C(CN)2) the complexes [(Cp2MoH2AgSC(O)Ph)2] (3), [((Cp2MoH2)2(AgSC(O)CH3)3)n] (4) and [(Cp2MoH2)2AgS(NHPh)C=C(CN)2] (6) were formed. The reaction of thiobenzamide and [(Cp2MoH2)2AgCl] gave the complex [(Cp2MoH2Ag(Cl)S(NH2)CPh)2] (5). Complexes 1 and 2 have a dimeric structure with the two dithio ligands bridging the two silver atoms. Complex 3 is also a dimer, however, the monothio ligands are coordinated with their single sulphur atoms to the silver atoms. In the polymer 4 the thioacetate ligand has the same bonding mode as in 3. The three-dimensional structure of 4 is built-up of parallel strings. In the dimer 5 the thiobenzamide ligands bind with the sulphur atom to a silver atom each. Complex 6 has a monomeric structure in which the silver atom is coordinated to two [Cp2MoH2] ligands and to the sulphur atom of the S(NHPh)C=C(CN)2 ligand. Compounds 1–6 were characterised analytically and spectroscopically and the structures were determined by single crystal X-ray analyses.  相似文献   

10.
The new terminal phosphinidene complex [Cp2Zr=PDmp(PMe3)] (Dmp=2,6-Mes2C6H3; 1) was prepared in 81% yield by the reaction of [Li(Et2O)][P(H)Dmp] with [Cp2Zr(Me)Cl] in the presence of excess PMe3. Compound 1 reacts with Ph2PCl to produce selectively the sterically congested triphosphane DmpP(PPh2)2 (2) and [Cp2ZrCl2] in high yields. The structure of 2 obtained by X-ray diffraction analysis of a single crystal reveals phosphorus–phosphorus bond lengths of 2.251(2) and 2.234(2) Å and a PPP bond angle of 105.46(6)°.  相似文献   

11.
Three families of heterobimetallic compounds were obtained by reaction of [Mo(CO)3(CH3CN)2(Cl)(SnRCl2)] (R = Ph, Me) with P(4-XC6H4)3 (X = Cl, F, H, Me, MeO). The type of compound obtained dependent on the solvent and concentration of the starting compound. So, [Mo(CO)2(CH3COCH3)2(PPh3)(Cl)(SnRCl2)]·nCH3COCH3 (R = Ph, n = 0.5; R = Me, n = 1) (type I) and [Mo(CO)3{P(4-XC6H4)3}(μ-Cl)(SnRCl2)]2 (R = Ph, X = Cl, F, H, Me, MeO; R = Me, X = Cl, F) (type II) were isolated from acetone solution in ca 0.05 M and 0.1 M concentrations, respectively. However, [Mo(CO)3(CH3CN) {P(4-XC6H4)3}(Cl)(SnRCl2)] (R = Ph, X = H; R = Me, X = Cl, F, H) (type III) were obtained from dichloromethane solution independently of the concentration used. All new complexes showed a seven-coordinate environment at molybdenum, containing Mo---Cl and Mo---Sn bonds. Mössbauer spectra indicated a four-coordination at tin for type III complexes.  相似文献   

12.
Oxidative addition of ethyl iodide to PdMe2(2,2′-bipyridyl) in (CD3)2CO gives the unstable “PdIMe2Et(bpy)”, which undergoes reductive elimination to form PdIR(bpy) (R = Me, Et), ethane, and propane. Ethene and palladium metal are also formed, and are attributed to decomposition of PdIEt(bpy) via β-elimination. Similar results are obtained with n-propyl iodide, although a palladium(IV) intermediate was not detected, but CH2=CHCH2X (X = Br, I) and PhCH=CHCH2Br give isolable complexes fac-PdXMe2(CH2CH=CHR)(L2) (R = H, Ph; L2 = bpy, phen). The propenyl complexes decompose at ambient temperature to form ethane, a trace of PdXMe(L2), and mixtures of [Pd(η3-C3H5)(L2)]X and [Pd(η3-C3H5)(L2)]-[Pd(η3-C3H5)X2]; for fac-PdBrMe2(CH2CH=CH2)(bpy) the major palladium(II) product is [Pd(η3-C3H5)(bpy)]Br.  相似文献   

13.
Cp2MoH2 reacts with methyl acrylate in the presence of acetylenes (L = C2H2, C2Me2, HCCtBu, HCCSiMe3, C2(SiMe3)2, HCCCH2OMe, HCCCH2NMe2) to form acetylene complexes Cp2Mo(L) 5. Protonation takes place with CF3CO2H at −80°C to give short-lived cations [Cp2MoH(L)+ (8) (L = C2Me2, HCCSiMe3, C2(SiMe3)2). The structure of [Cp2MoH{η2-C2(SiMe3)2}]PF6(9) was determined by an X-ray diffraction study.  相似文献   

14.
The heterobimetallic trinuclear sulfido clusters [(Cp*Ir)23-S)2MCl2] (M=Pd (3), Pt (4); Cp*=η5-C5Me5) were synthesized from the dinuclear hydrogensulfido complex [Cp*IrCl(μ-SH)2IrCp*Cl] (2) and [MCl2(COD)] (COD=cycloocta-1,5-diene), while the reaction of 2 with [Pd(PPh3)4] afforded the cationic trinuclear cluster [(Cp*Ir)23-S)2PdCl(PPh3)]Cl (5). Clusters 3 and 4 reacted with PPh3 to give a series of mono and dicationic clusters including 5, while the dicationic clusters [(Cp*Ir)23-S)2M(dppe)][BPh4]2 (M=Pd (9), Pt (10); DPPE=Ph2PCH2CH2PPh2) were obtained by the reaction with dppe followed by anion metathesis. The molecular structures of 5·CH2Cl2, 9·CH3COCH3, and 10·CH3COCH3 were determined by X-ray crystallography. Clusters 3 and 4 were found to catalyze the addition of alcohols to alkynes to give the corresponding acetals. Internal 1-aryl-1-alkynes were transformed by cluster 3 into the corresponding 2,2-dialkoxy-1-arylalkanes with high regioselectivity up to 99:1, while cluster 4 was a much less regioselective catalyst.  相似文献   

15.
The reaction of imidoylzirconocene complexes with zirconocene hydrides yields (N-alkylamido)zirconocene complexes. For a mechanistic study, the specifically substituted imidoylzirconocene complexes 3b–3d have been prepared and treated with the oligomeric metal hydrides (Cp2ZrH2)x (1b) and (Cp2ZrHCl)x (1c). (N-Benzyl formimidoyl)zirconocene chloride (3b) was obtained by treating 1c with benzyl isonitrile 2a. Treatment of dimethylzirconocene with 2a gave (N-benzyl acetimidoyl)methylzirconocene (3c), which was treated with PhICl2 to give (N-benzylacetimidoyl)zirconocene chloride (3d). The reaction of 3d with (Cp2ZrH2)x (1b) yielded (N-benzyl-N-ethylamido)zirconocene chloride (4b) as the only identified product. A 1/1 mixture of 4b and methylzirconocene chloride was obtained upon treatment of 3c with (Cp2ZrHCl)x (1c); in contrast, the reaction of 1c with 3b gave an equimolar mixture of Cp2ZrCl2 and (N-benzyl-N-methylamido)zirconocene chloride (4c). Reaction paths through binuclear (μ-CHR′=NR) zirconocene intermediates are proposed to explain these experimental observations.  相似文献   

16.
Reactions of -, β- and γ-hydrogen elimination in cyclopentadienylnickel compounds formed in the reactions of nickelocene with lithium or magnesium compounds are discussed. Elimination of -hydrogen from CpNiR where R is CH3, CH2C(CH3)3, CH2Si(CH3)3, CH2Ph or CH=C(CH3)2 leads to the formation of trinickel clusters (CpNi)3CR′, bis(cyclopentadienyl)(μ-cyclopentadiene)dinickel and (η5-cyclopentadienyl)(η3-cyclopenteny)nickel. β-hydrogen and γ-hydrogen elimination in vinylnickel compounds not possesing -hydrogen have been studied. Elimination and transfer of hydrogen forms (η3-allyl)(η5-cyclopentadienyl)nickel compounds. The mechanisms of these reactions are discussed.  相似文献   

17.
The reaction of the metallocene dichlorides Cp2MCl2 (Cp = η5-C5H5; M = Ti, Zr, Hf, Mo, W) and Cp2′TiCl2 (Cp′ = η5-C5H4CH3) with equimolar amounts of dilithium-benzene-o-diselenolate, 1,2-(LiSe)2C6H4, gives the chelate complexes Cp2M(Se2C6H4) (M = Ti (I), Zr (II), Hf (III), Mo (IV), W (V)) and Cp2′Ti(Se2C6H4) (VI). CpTiCl3 reacts with 1,2-(LiSe)2C6H4 to give CpTiCl(Se2C6H4) (VII). The ring inversion activation parameters for I–VI can be determined by means of temperature-dependent 1H NMR spectroscopy in solution. The fragmentation behaviour of I–VII in the mass spectrometer has been investigated by pursuing metastable transitions, using linked-scan techniques.  相似文献   

18.
Recent results (post-1990) on the synthesis and structures of bis(trimethylsilyl)methyls M(CHR2)m (R = SiMe3) of metals and metalloids M are described, including those of the crystalline lipophilic [Na(μ-CHR2)], [Rb(μ-CHR2)(PMDETA)]2, K4(CHR2)4(PMDETA)2, [Mg(CHR2)(μ-CHR2)], P(CHR2)2 (gaseous) and P2(CHR2)4, [Yb(CHR2)2(OEt2)2] and [{Yb(CR3)(μ-OEt)(OEt2)}2]; earlier information on other M(CHR2)m complexes and some of their adducts is tabulated. Treatment of M(CHR2) (M = Li or K) with four different nitriles gave the X-ray-characterized azaallyls or β-diketinimates , and (LL′ = N(R)C(tBu)CHR, L′L′ = N(R)C(Ph)C(H)C(Ph)NR, LL″ = N(R)C(Ph)NC(H)C(Ph)CHR, R = SiMe3 and Ar = C6H3Me2-2,5). The two lithium reagents were convenient sources of other metal azaallyls or β-diketinimates, including those of K, Co(II), Zr(IV), Sn(IV), Yb(II), Hf(IV) and U(VI)/U(III). Complexes having one or more of the bulky ligands [LL′], [L′L′], [LL], [LL″], [L″L], [LL] and [{N(R)C(tBu)CH}2C6H4-2]2− are described and characterized (LL = N(H)C(Ph)C(H)C(Ph)NH, L″L = N(R)C(tBu)C(H)C(Ph)NR, LL = N(R)C(tBu)CHPh). Among the features of interest are (i) the contrasting tetrahedral or square-planar geometry for and , respectively, and (ii) olefin-polymerization catalytic activity of some of the zirconium(IV) chlorides.  相似文献   

19.
The reaction of the anionic mononuclear rhodium complex [Rh(C6F5)3Cl(Hpz)]t- (Hpz = pyrazole, C3H4N2) with methoxo or acetylacetonate complexes of Rh or Ir led to the heterodinuclear anionic compounds [(C6F5)3Rh(μ-Cl)(μ-pz)M(L2)] [M = Rh, L2 = cyclo-octa-1,5-diene, COD (1), tetrafluorobenzobarrelene, TFB (2) or (CO)2 (4); M = Ir, L2 = COD (3)]. The complex [Rh(C6F5)3(Hbim)] (5) has been prepared by treating [Rh(C6F5)3(acac)] with H2bim (acac = acetylacetonate; H2bim = 2,2′-biimidazole). Complex 5 also reacts with Rh or Ir methoxo, or with Pd acetylacetonate, complexes affording the heterodinuclear complexes [(C6F5)3Rh(μ-bim)M(L2)] [M = Rh, L2 = COD (6) or TFB (7); M = Ir, L2 = COD (8); M = Pd, L2 = η3-C3H5 (9)]. With [Rh(acac)(CO)2], complex 5 yields the tetranuclear complex [{(C6F5)3Rh(μ-bim)Rh(CO)2}2]2−. Homodinuclear RhIII derivatives [{Rh(C6F5)3}2(μ-L)2]·- [L2 = OH, pz (11); OH, StBu (12); OH, SPh (13); bim (14)] have been obtained by substitution of one or both hydroxo groups of the dianion [{Rh(C6F5)3(μ-OH)}2]2− by the corresponding ligands. The reaction of [Rh(C6F5)3(Et2O)x] with [PdX2(COD)] produces neutral heterodinuclear compounds [(C6F5)3Rh(μ-X)2Pd(COD)] [X = Cl (15); Br (16)]. The anionic complexes 1–14 have been isolated as the benzyltriphenylphosphonium (PBzPh3+) salts.  相似文献   

20.
Reactions of FcCCH (a), HCCCCFc (b) and FcCCCCFc (c) with Ru3(CO)10(NCMe)2 (all) and Ru3(μ-dppm)(CO)10 (b and c only) are described. Among the products, the complexes Ru33-RC2R′)(μ-CO)(CO)9 (R=H, R′=Fc 1, CCFc 2; R=R′=Fc 5), Ru3(μ-H)(μ3-C2CCFc)(μ-dppm)(CO)7 3, Ru33-FcC2CCFc)(μ-dppm)(μ-CO)(CO)7 6 and Ru33-C4Fc2(CCFc)2}(μ-dppm)(μ-CO)(CO)5 7 were characterised, including single-crystal structure determinations for 1, 3, 5 and 7; that of 7 did not differ significantly from an earlier study of a mixed CH2Cl2–C6H6 solvate.  相似文献   

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