首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The preparation of the compounds {(η-C5H5)MoX}2{μ-(η5-C5H45-C5H4)} (X = Me, PhCH2, Me3SiCH2, Br) and {(η-C5H5)MoY2}2{μ-(η5-C5H45-C5H4)}, (Y = H, I, SMe, S-n-Bu) is described. Photolysis of {(η-C5H5)MoH}2 {μ-(η15 -C5H4)}2 and {(η-C5H5)MoH}2{(η5-C5H45-C5H4)} in benzene leads to a compound of stoichiometry C20H18Mo2.  相似文献   

2.
A large variety of (η5-borole)cobalt complexes have been prepared starting with η-(CO)2[Co(CO)(η5-C4H4BR)]2(CoCo) (IIIa: R = Me, IIIb: R = Ph), including inter alia, the sandwich complexes CpCo(η5-C4H4BR) (VIIa, b), the triple-decked complexes η-(η5-C4H4BR)[Co(η5-C4H4BR)]2 (VIIIa, b) and μ-(η5-C4H4BR)(FeCp)[Co(η5-C4H4BR)] (X, R = Ph), the dinuclear complex μ-(CO)2[Fe(CO)Cp][Co(CO)(η5-C4H4BPh)](FeCo) (IX), and salts M[Co(η5-C4H4BR)2](XVa, b: M = Na; XVIa, b: M = NMe4; XVII: M = Cs, R = Ph). The anions [Co(η5-C4H4BR)2] readily undergo stacking reactions to form multiple-decked complexes such as the triple-decker compounds μ-(η5-C4H4BR)[Mn(CO)3][Co(η5-C4H4BR)] (XIIa, b), μ-(η5-C4H4BR)[Co(η5-C4H4BR)][Rh(η-1,5-COD)] (XVIII), [NMe3Ph][μ-η5-C4H4BPh){Cr(CO)3}{Co(η5-C4H4BPh)}] (XX), and the quadruple-decker complex Ru[μ-(η5-C4H4BR)Co(η5-C4H4BR)]2 (XXI). The monofacially bound η5-borole ligands in VIIb and VIIIb shows regiospecific H/D exchange, at the α position of the boron, on treatment with CF3CO2D at room temperature. VIIb undergoes a Friedel-Crafts substitution to give the 2-acetyl derivative XXIV with MeCoCl/SnCl4 in CH2Cl2 at room temperature.The structure of VIIIa, as determined by X-ray diffraction studies is that of a typical triple-decker compound with nearly coplanar rings. The three borole rings form a helix with torsional angles of 59.8 and 72.2°. All intra-ring bond distances of the central ligand are longer than those of the outer ligands. The metal-ligand interaction is somewhat stronger for the outer ligands than for the central ligand.  相似文献   

3.
《Polyhedron》1999,18(20):2583-2595
The reaction of the novel ferrocenyl Schiff base: [(η5-C5H5)Fe{(η5-C5H4)-CH=N-(C6H4-2-C6H5)}] (1) with Na2[PdCl4] and Na(CH3COO)·3H2O in a 1:1:1 molar ratio in methanol is reported. In this reaction two different di-μ-chloro-bridged cyclopalladated complexes: [Pd{[(η5-C5H3)-CH=N-(C6H4-2-C6H5)]Fe(η5-C5H5)}(μ-Cl)]2 (2a) and [Pd{[(C6H4-2-C6H4)-N=CH-(η5-C5H4)]Fe(η5-C5H5)}(μ-Cl)]2 (2b) can be formed depending on the experimental conditions. Compounds 2a and 2b, which differ in the nature of the metallated carbon atom (Csp2,ferrocene or Csp2,biphenyl, respectively), undergo cleavage of the ‘Pd(μ-Cl)2Pd’ bridges in the presence of thallium (I) acetylacetonate, deuterated pyridine or triphenylphosphine giving the monomeric derivatives: [Pd(CN)(acac)] (3a, 3b) and [Pd(CN)Cl(L)] {with L=py- d5(4a, 4b), PPh3(5a, 5b)}. The reactions of 2 with 1,2-bis(diphenylphosphino)ethane (dppe) reveal that the two isomers (2a and 2b) exhibit different reactivity versus dppe. These results have been interpreted on the basis of steric effects.  相似文献   

4.
Preliminary reactions of the metal stabilized carbocationic species [(η-C5H5)Ni(μ-η2(Ni),η3(Mo)-HC2CMe2)Mo(CO)2(η-C5H4Me)]+ BF4 (Ni-Mo) with nucleophiles are reported. The Ni-Mo cationic propargylic complex undergoes nucleophilic attack by sodium methoxide to regenerate the neutral μ-alkyne complex [(η-C5H5)Ni{μ-η22-HC2CMe2(OMe)}Mo(CO)2(η-C5H4Me)] (Ni-Mo), from which the stabilized carbocation was originally derived by protonation. The new complexes [(η-C5H5)Ni{μ-η22-HC2CMe2(C5H5)}Mo(CO)2(η-C5H4Me)] (Ni-Mo), which exist as an inseparable mixture of 1(c)-1,3- and 2(c)-1,3-cyclopentadienyl isomers, were also obtained. When the Ni-Mo cations were treated with potassium t-butoxide, the alkyne isomers with pendant 1(c)-1,3- and 2(c)-1,3-cyclopentadienyl groups are also formed. The μ-hydroxyalkyne complex [(η-C5H5)Ni{μ-η22-HC2CMe2(OH)}-Mo(CO)(η-C5H4Me)] (Ni-Mo) was also isolated concurrently, and presumably arises from nucleophilic attack of fortuitously present hydroxide ions in the BuO reagent on the Ni-Mo cation. When NaBH4 was added to the Ni-Mo propargylic, nucleophilic attack by hydride resulted and the μ-iPrC2H heterobimetallic complex [(η-C5H5)Ni{μ-η22-HC2Pri}Mo(CO)2(η-C5H4Me)] (Ni-Mo) was recovered in good yield. Small quantities of other side-products were isolated and characterized spectroscopically. Some tantalizing differences in reactivity were observed when the corresponding Ni-W stabilized carbocation was reacted with methoxide ions. When the not fully characterized solid formed by protonating [(η-C5H5)Ni(μ-η22-{HC2CMe2)(OMe)}W(CO)2(η-C5H4Me)] (Ni-W) was treated with methoxide ions, regioisomers (1(c)-1,3- and 2(c)-1,3-cyclopentadienyl species) of composition [(η-C5H5)Ni{μ-η22-HC2CMe2(C5H5)}W(CO)2(η-C5H4Me)] (Ni-W) were formed. Direct reaction of the pure cation [(η-C5H5Niμ-η23-HC2CMe2)W(CO)2(η-C5H4Me)]+ (Ni-W) with methoxide also generated the same 1(c)-1,3- and 2(c)-1,3-cyclopentadiene-substituted alkyne complexes. Unlike the case with the Ni-Mo complexes, the initial μ-HC2CMe2(OMe) species was not regenerated.  相似文献   

5.
6.
The protonated species [Fe2(η-C5H5)2(CO)2(η-CO){μ-CN(Me)H}]X, [Fe2(η-C5H5)2(CO)(CNMe)(μ-CO){μ-CN(Me)H}][X], and [Fe2(η-C5H5)2(CO)2{η-CN(Me)H}2][X]2 react with one equivalent of AgY. The Ag+ and one H+ act together as a two-electron oxidant. Silver metal is precipitated quantitatively and the substrates cleaved to give mono-nuclear products of the type (a) [Fe(η-C5H5)(CO)(L)X] and [Fe(η-C5H5(CO)(L)Y] or (b) Fe(η-C5H5(CO)(L)(CNMe)][X] (L = CO, CNMe). If X and Y are both coordinating anions such as NO3, I, or Br or the solvent is MeCN products of type (a) are usually obtained with X = Y = MeCN+ if acetonitrile is used as the solvent. However, if either X or Y is a non-coordinating anion such as BF4 or PF6 and methanol is the solvent, the products are usually those of type (b). When X = [p-MeC6H4SO3], both types of products are obtained in significant amounts. If two equivalents of Ph3P are added to the methanol solution of [Fe2(η-C5H5)2(CO)2{-CN(Me)H}2[BF6]2, no reaction takes place until the third equivalent of AgNO3 has been added. The products have been isolated and characterized by analysis and infrared spectroscopy. The previously unreported [Fe2(η-C5H5)2(CO)(CNMe)(η-CO){η-CN(Me)H}] X salts are described for X = BF4, PF6, Br · 2H2O, I · H2O, NO3 · 0.5H2O, and p-MeC6H4SO3.  相似文献   

7.
Reaction of Li{(η5-C5H4Me)Mn(CO)2]C(O)Ph]} with one equivalent of RSiMe2Cl yields (η5-C5H4Me)Mn(CO)2[C(Ph)(OSiMe2R)] for R  CH3, CHCH2, and CH2CHCH2 (1a–c, respectively). Low temperature photolysis of the vinyl derivative, 1b, results in formation of a chelated manganese siloxycarbene-alkene complex, (η5-C5H4Me)MN(CO)[C(Ph)(η2-OSiMe2CHCH2)]. (2). Photolysis of the allyl derivative, 1c, under similar conditions leads to uncharacterized decomposition products. Infrared, 1H, 13C, and 29Si NMR data are reported for these new siloxycarbenemanganese derivatives.  相似文献   

8.
The salts [Fe2η55-C5H4CH{NMe3)CH(NMe2)C5H4}(CO)2(μ-CO)2][X] (X = I or SO3CF3) are the synthetic precursors to a wide range of [Fe2(η-C5H5)2(CO)2(μ-CO)2] derivatives in which the two cyclopentadienyl ligands are joined by a two-carbon bridge.  相似文献   

9.
The treatment of the aquocation [Co(η3-2-MeC3H4)(η5-C5H5)(H2O]+ with neutral and anionic ligands gives new cobalt complexes containing cations [Co(η3-2-MeC3H4)(η5-C5H5)L]n+, n = 0; L = CN, CH3COO, CF3COO and n = 1; L = P(p-MePh)3, NCEt, NCPh, CNCy, dppm and [{Co(η3-2-MeC3H4)(η5-C5H5)}2 (μ-L-L)]2+, L-L = bipy, dppm. The neutral cyano complex reacts with various electrophiles to give cationic isocyanide complexes containing the cation [Co(η3-2-MeC3H4)(η5-C5H5)(CNR)]+, which have been isolated in low yields. Chemical behaviour and structural implications of IR and 1H and 13C NMR spectra are discussed.  相似文献   

10.
Heteroleptic rhodium(I) complexes with the general formulations [(η4-C8H12)Rh(L)] [η4-C8H12 = 1,5-cyclooctadiene; L = 5-(4-cyanophenyl)dipyrromethene, cydpm; 5-(4-nitrophenyl)dipyrromethene, ndpm; and 5-(4-benzyloxyphenyl)dipyrromethene, bdpm; 5-(4-pyridyl)dipyrromethene, 4-pyrdpm; 5-(3-pyridyl)dipyrromethene, 3-pyrdpm] have been synthesized. The complex [(η4-C8H12)Rh(4-pyrdpm)] have been used as a synthon in the construction of homo-bimetallic complex [(η4-C8H12)Rh(μ-4-pyrdpm)Rh(η5-C5Me5)Cl2] and hetero-bimetallic complexes [(η4-C8H12)Rh(μ-4-pyrdpm)Ir(η5-C5Me5)Cl2], [(η4-C8H12)Rh(μ-4-pyrdpm)Ru(η6-C10H14)Cl2] and [(η4-C8H12)Rh(μ-4-pyrdpm)Ru(η6-C6H6)Cl2]. Resulting complexes have been characterized by elemental analyses and spectral studies. Molecular structures of the representative mononuclear complexes [(η4-C8H12)Rh(ndpm)] and [(η4-C8H12)Rh(4-pyrdpm)] have been authenticated crystallographically.  相似文献   

11.
The stereochemistry of propylene insertion/propagation reactions with a variety of Cs symmetric fluorenyl- containing single site catalysts is discussed. Our recent results indicate that independent of the chemical composition of the ancillary ligand fragments, or nature of the transition metal, active sites with local Cs symmetry and enantiotopic coordination positions behave syndioselectively in the general context of chain migratory insertion mechanism. Perfect bilateral symmetry neither exists nor is required in these processes. In this context the mechanism of syndiospecific polymerization is revisited by taking into account the structural characteristics and catalytic behavior of the original metallocene based (η5-C5H4-CMe25-C13H8) MCl2/ MAO; M = Zr ( 1 ), Hf ( 2 ) catalyst systems and new syndiotactic specific systems including (η5-C5H4-CPh2-η5-3,6-di-tBut-C13H6)ZrCl2 ( 3 ), η15-(μMe2Si)(3,6-di-tBut-Flu)(t-ButN)MCl2/ MAO; M =Ti ( 4 ), Zr ( 5 ) and η15-(μMe2Si)(2,7-di-tBut-Flu)(t-ButN)MCl2/ MAO; M = Ti ( 6 ), Zr ( 7 ).  相似文献   

12.
Reaction of [MoCo(CO)5(PPh3)25-C5H5)] (1) with diphenylacetylene in tetrahydrofuran at 50 °C yielded two heterobimetallic compounds, [MoCo(CO)4.(PPh3){μ-PhC ? CPh}(η5-C5H5)] (4) and [MoCo(CO)5{μ-PhC ? CPh} (η5-C5H5)] (5). However, an unexpected product, Co(CO)2(μ-CO)(μ:η24-C4Ph4)Co(CO)2(PPh3) (6), was observed while attempting to grow the crystals for structural determination of 4. The X-ray crystal structure of 6 was determined: triclinic, $ {\rm P}\bar 1 $, a = 11.654(2) Å, b = 12.864(2) Å, c = 13.854(2) Å, α = 89.67(2)°, β = 86.00(2)°, γ= 83.33(2)°, V = 2057.9(6) Å3 Z=2. In 6, two cobalt fragments are at apical and basal positions of the pseudo-pentagonal pyramidal structure, respectively. The electron count for the apical cobalt fragments is 20, which is rather unusual. It is believed that 6 was formed after the fragmentation and recombination of the fragmented species of 4.  相似文献   

13.
The compounds [M{(CH2)4C(η-C5H4)2}(η-C5H5)Cl] (M=Zr*, Hf), [M{(CH2)4C(η-C5H4)2}(η-C5H5)Me] (M=Zr, Hf), [(η-C5H5)MCl2{(CH2)4C(η-C5H4)2}MCl2(η-C5H5)] (M=Zr, Hf), [(η-C5H5)ZrCl2{(CH2)4C(η-C5H4)(η-C9H6)}ZrCl2(η-C5H5)], [(η-C5H5)MMe2{(CH2)4C(η-C5H4)2}MMe2(η-C5H5)] (M=Zr, Hf), [(η-C5H5)ZrCl2{(CH2)4C(η-C5H4)2}HfCl2(η-C5H5)], [(η-C5H5)MCl2{(CH2)4C(η-C5H4)2}Rh(η-C8H12)] (M=Zr*, Hf), [(η-C5H5)ZrCl2{(CH2)4C(η-C5H4)2}TiCl3], [(η-C5H5)ZrMe2{(CH2)4C(η-C5H4)2}HfMe2(η-C5H5)], [(η-C5H5)MMe2{(CH2)4C(η-C5H4)2}Rh(η-C8H12)] (M=Zr*, Hf) have been prepared and characterised. * indicates the crystal structure has been determined. Their catalytic properties for ethene and propene polymerisation have been explored.  相似文献   

14.
Dimeric palladium(I) complexes of the type [μ-(η3-C5H5)-μ-XPd2(PR3)2](X  Br, R  i-Pr, Ph, Cy; X  Cl, I, R  i-Pr) have been prepared by reduction of the complexes [(ν5-C5H5)(PR3)PdX] with a variety of reducing agents (Mg,Na/Hg, LiAlH(t-BuO)3, LiAlH4, NaBH4, n-BuMgBr). PMR and IR data and some properties of the new complexes are reported.  相似文献   

15.
《Tetrahedron: Asymmetry》1998,9(22):4035-4041
The resolution of cycloplatinated ferrocenylketimines was carried out by using S-leucine as chiral auxiliary and a pair of diastereomers was obtained. The optically active derivatives of the cycloplatinated ferrocenylketimines have been prepared and characterized. The structures and absolute configurations of (−)-(Sp,S)-[Pt{(η5-C5H3CMeNC6H4-4-CH3)Fe(η5-C5H5)}(S-leu)] and (−)-(Sp)-[Pt{(η5-C5H3CMeNC6H4-4-Br)Fe(η5-C5H5)}(PPh3)Cl] were determined by X-ray diffraction, on the basis of which the absolute configurations of other optically active compounds studied were ascertained.  相似文献   

16.
The complex η55-(CO)3Mn(C5H4-C5H4)(CO)2Fe-η15-C5H4Mn(CO)3 was synthesized by the reaction of η5-Cp(CO)2Fe-η15-C5H4Mn(CO)3 with BunLi (THF, ?78 °C) and then with anhydrous CuCl2. The complex μ-(C≡C)[C5H4(CO)2Fe-η15-C5H4Mn(CO)3]2 was prepared by the reaction of η5-IC5H4(CO)2Fe-η15-C5H4Mn(CO)3 with Me3SnC≡CSnMe3 (2:1) in the presence of Pd(MeCN)2Cl2.  相似文献   

17.
The synthesis and characterization of two new heterotetrametallic complexes are described. Reaction of [Cr(CO)36-C6H5)CC-{(η5-C5H4)Fe(η5-C5H5)}](1) with Co2(CO)8 or Cp2Mo2(CO)4 afford the heterotetrametallic complexes [Cr(CO)36-C6H5){Co2(CO)622-CC–}(η5-C5H4)Fe(η5-C5H5)}](2), and [Cr(CO)36-C6H5){Mo2Cp2(CO)422-CC–}(η5-C5H4)Fe(η5-C5H5)](3) in 80% and 41% yield, respectively. All complexes have been characterized by elemental analysis, multinuclear (1H, 13C) NMR, and by single-crystal X-ray diffraction studies for 1 and 3. Structural data reveal that the coordination of dimolybdenum moiety to the alkyne unit influence the orientation of the carbonyl groups coordinated to the chromium as well as the Cp rings bound to the iron metal centre.  相似文献   

18.
Synthetic routes to the cationic complexes [η5-C9H7Fe(CO)[2L]+, (L = CO, phosphine, phosphite, nitrile, pyridine) have been investigated. The most versatile method is oxidation of the dimer [η5-C9h7Fe(CO)2]2 with ferricinium ion. in the presence of the appropriate ligand. [η5-C9H7Fe(CO)3]+ is best prepared by oxidation of the dimer with Ph3CBF4. This tricarbonyl cation readily loses one CO group on reactiom with phosphines and P(OCH3). The acentonitrile ligand [η5-C9H7Fe(CO)2CH3CN]+ can also be replaced bny phosphines. Finally, reactions of η5-C9H7Fe(CO)2X, (X = Br, I) with phosphines also yield cationic products isolatedas PF6 salts.  相似文献   

19.
{Cu4Br5[(η 5-C5H4PPh2)(η 5-C5H5)Co]4}[PF6]3, [(η 5-C5H4PPh2)(η 5-C5H5)Co]+ = ((η 5-cyclopentadienyl)[η 5-1-(diphenylphosphino) cyclopentadienyl] cobaltocenium) and {Ag(NO3)(CH3COCH3)[(η 5-C5H4PPh2)(η 5-C5H5)Co]} n [PF6] n have been synthesized and characterized by elemental analyses, infrared spectroscopy, X-ray diffraction techniques, and by cyclic voltammetry. {Cu4Br5[(η 5-C5H4PPh2)(η 5-C5H5)Co]4}[PF6]3 contains four coplanar copper atoms bridged by four μ-Br and one central μ 4-Br occupying the apex of a square pyramid, and {Ag(NO3)(CH3COCH3)[(η 5-C5H4PPh2)(η 5-C5H5)Co]} n [PF6] n affording a 1-D coordination zigzag polymer.  相似文献   

20.
The following compounds were prepared and their pyrolysis in a stream of argon was studied: (η5-C5H5)2Ti(C?CC6H5)2, (η5-C5H4SiMe3)2-Ti(SH)2, [(η5-C5H5)Ti(μ-CH2)]2, (η5-C5H5)2ZrR2-(R?CH2, CH2C6H5, N(CH3)2), (η5-C5H4CH3)2-Zr(C?CC6H5)2, [(η5-C5H4SiMe3)2Zr(μ-S)]2, [(η5-C5H4SiMe3)2Hf(μ-S)]2 and (η5-C5H4SiMe3)2Hf-(C?CC6H5)2. The products of bulk pyrolysis of these materials were formed in 20–40% yield, based on the charged sample weight, and consisted mainly of titanium carbide together with small amounts of amorphous carbon.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号