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1.
Summary The [2.2]paracyclophane cluster, Ru6C(CO)14( 3- 2 2 2-C16H16) (1), undergoes reaction with Me3NO and triphenylphosphine to yield Ru6C(CO)13( 3- 2 2 2-C16H16)(PPh3) (2), which may also be produced from (1) by thermolysis with PPh3 in THF. Compound (2) has been fully characterized in solution by spectroscopy and in the solid state by a single crystal X-ray diffraction analysis at 277 K, and its structure is compared with that of the parent cluster, (1). Using the same synthetic procedures, the tricyclohexylphosphine analogue, Ru6C(CO)13( 3- 2 2 2-C16H16)(PCy3) (3), has also been prepared and characterized spectroscopically. A comparison of the chemical shifts of the 577-01 protons in the 1H-n.m.r. spectra of compounds (1)–(3) together with a variety of other [2.2]paracyclophane and benzene clusters has been made.  相似文献   

2.
The redox potentials of new Cr, Mn, and Fe polynuclear ladder complexes, (5-Cp)Fe(CO)2(1,5-C5H4)Fe(CO)2(1,5-C5H4)Mn(CO)3, (5-Cp)Fe(CO)2(1,5-C5H4)Mn(CO)3, (5-Cp)Fe(CO)2(1,6-Ph)Cr(CO)3, (5-Cp)Fe(CO)2(1,5-C5H4)Fe(CO)2CH2Ph, (5-Cp)Fe(CO)2(1,6-CH2Ph)Cr(CO)3, were measured and the mechanism of their electrochemical oxidation and reduction was suggested. It was shown that the - or -bonds of the bridging ligand can be cleaved selectively by applying cathodic or anodic potentials, respectively. On the basis of the obtained electrochemical data, a mechanism is suggested for the rearrangement observed when the complexes are metallated by butyllithium.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 362–366, February, 1995.This work was carried out with financial support from the Russian Foundation for Basic Research (Project No 94-03-08628a).  相似文献   

3.
Reaction of [(3-C4H7)2Rh(CH3CN)2]PF6(3-C4H7 = -methallyl) with [n-Bu4N](VO3) gives a new 3-allyl cluster [n-Bu4N]2[{(3-C4H7)2Rh}2 (V4O12)] (I) which is readily converted into a diene cluster, [n-Bu4N]2 [{(4-C8H14)Rh}2(V4O12)] (II) (C8H14=2,5-dimethyl-1,5-hexadiene) by reacting with CO or P(OEt)3;I andII have been characterized crystallographically.  相似文献   

4.
The quantum-chemical DFT calculations of the Cp2Zn structure confirm the conclusion made earlier from the vibrational spectra that the sandwich structure (5-C5H5)2Zn (A) is not energetically favorable and more favorable are the close in energy -structure (5-C5H5)(1-C5H5)Zn (B) and -structure (1-C5H5)2Zn (C). The vibrational spectra of structures B and C with the DFT-derived force fields were calculated. A comparison of the calculated spectra of the isolated Cp2Zn molecules with the experimental data gives no way of deciding between the B and C structures. It is most likely that the molecule is nonrigid and experiences a strong influence from the nearest environment in solution or in the crystalline state.  相似文献   

5.
It was found that the 16-C6H5Cr(CO)3 ligand migrates into the cyclopentadienyl ring when the 5-C5H5(CO)2Fe 16-C6H5Cr(CO)3 binuclear complex is metallated with BunLi. Under the same conditions, no migration of the phenyl ligand in the 5-C5H5(CO)2Fe 1-C6H5 complex was observed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 325–326, February, 1994.  相似文献   

6.
It has been shown by cyclic voltammetry in a THF medium in the temperature range from –70 °C to +20 °C that one-electron electrochemical reduction of (6-C13H10)Cr(CO)3 (1) to the corresponding 19-electron anion radical (1 ) is accompanied by splitting off of a H atom to form the 18-electron carbon-centered anion (6-C13H9)Cr(CO)3 (2 ), which at room temperature undergoes intramolecular haptotropic isomerization to the metal-centered (5-C13H9)Cr(CO)3 ( 3) anion. The reversible one-electron reduction of3 to the corresponding 19-electron radical dianion3 2.– induces 5 6 interannular isomerization. In contrast to the equilibrium shift to the 5-isomer in 18-electron complexes 2 and 3, in their 19-electron analogs the equilibrium is shifted to the 6-isomer.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 48–53, January, 1994.This work was carried out with financial support from the Russian Foundation for Basic Research (no. 93-03-5209)  相似文献   

7.
The problem of existence of 3—-complexes of C60 fullerene with transition metal atoms is discussed. The complexes C60R3Co(CO)3 (R = H, F, Cl, Br), C60H3NiCp, and C60H3Fe(CO)Cp, where C60R3 is an allyl derivative of C60 fullerene, were shown to be sufficiently stable. In these complexes the metal atoms are 3—-bound to the fullerene cage. In contrast to this, the metal atoms in the C60H3Li and C60H3FeCp complexes are 5—-coordinated to the carbon cage. Density functional calculations were carried out with the Perdew—Burke—Ernzerhof exchange-correlation potential (PBE). It was concluded that the type of bonding in the complexes of allyl derivatives of C60 fullerene depends on the nature of the species attached. Among the systems studied, the maximum energy of the 3—-bond was obtained for the C60H3NiCp complex. The results obtained can be useful in the design of synthesis of new fullerene derivatives with the 3—-coordination of the transition metal atoms to the carbon cage.  相似文献   

8.
Photochemical reactions of M(CO)3(5-C9H7), where M=Mn (1) or Re (2), with indene have produced 2-indene complexes M(CO)2(2-C9H8)(5-C9H7), where M=Mn (3) or Re (4). Deprotonation of complex3 witht-BuOK in THF at –60 °C gives the anion [Mn(CO)2(1-C9H7)(5-C9H7) (5), in which there occurs a rapid interchange of the Mn(CO)2(5-C9H7) group between positions 1 and 3 in the 1-indenyl ligand. The reaction of complex4 with Ph3CPF6 in CH2Cl2 at 0 °C leads to the complex [Re(CO)2(3-C9H7)(5-C9H7)PF6, whereas the similar reaction of complex3 gives only decomposition products even at –20 °C.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1280–1285, July, 1993.  相似文献   

9.
The metallocene derivative (21:2-Gaz)Lu(5-Cp)(DME) (1) (Gaz is 7-isopropyl-1,4-dimethylazulene) was prepared by reduction of guaiazulene with the lutetium naphthalene complex (5-Cp)Lu(21:2-C10H8)(DME) in 1,2-dimethoxyethane (DME). Complex 1 crystallized from a solution as blue crystals. According to the results of X-ray diffraction analysis, molecule 1 has a skewed pseudo-sandwich structure in which the Lu atom is 5-coordinated by the cyclopentadienyl ring and 21:2-coordinated by the seven-membered ring of the guaiazulene ligand. The coordination sphere of the metal atom in complex 1 is completed with the chelating DME molecule.  相似文献   

10.
Spectral detectivities (D *()) are commonly used to characterize the sensitivity of infrared detectors, but for most spectroscopic purposes they are very misleading.For photon detectorsspectral detector quantum efficiencies ( q ()) are needed in order to calculate the (S/N) ratio for the photon-noise limited situation. An equation to calculate q(#x03C3;) fromD *() values is presented. The results for some common IR-detectors are surprising.As an application for the use of q () values theS/N ratio of an FT-IR spectrum from an optimized FTS instrument under photon-limited conditions is given.  相似文献   

11.
Summary [RuCl2(CO)2] n reacts with the Schiff base 1-acetylferrocenethiosemicarbazone, [Fe(-Cp)(-C5H4MeC=NN-HCSNH2)] to give [Fe(-Cp)(-C5H4MeC=NN-HCSNH2)RuCl2(CO)2] and with 1-acetylferrocenesemicarbazone [Fe(-Cp)(-C5H4MeC=NN-HCSNH2)] to give [Fe(-Cp)(-C5H4MeC=NN-HCSNH2)RuCl2-(CO) 2]. Spectroscopic data indicate that the Schiff bases act as bidentate ligands and coordinate to ruthenium via the hydrazinic N and either the S or O atoms, respectively, giving stable heterobimetallic complexes, which have been characterized by i.r. and 1H-n.m.r. spectroscopies, and elemental analyses.Part of this work was presented at the First International Conference in Chemistry and its applications in Doha, Qatar, 1993.  相似文献   

12.
In this article we review the synthesis, reactivity, and characterization of a number of clusters bearing the [2.2] paracyclophane ligand with nuclearities ranging from two to eight. Particular attention is focused on the different coordination modes that paracyclophane adopts; these being µ1- 6, µ2- 3 : 3, µ3- 1 : 2 : 2, and µ3- 2 : 2 : 2. Structural modifications which take place within the ring system on bonding in these various modes are also discussed.  相似文献   

13.
Stacking reactions of the dicationic fragments [LM]2+ (LM = (-C6H6)Ru, (-C6H3Me3)Ru, or (-C5Me5)Rh) with the complex (-C5H5)Co(-C4H4BCy) (Cy = cyclo-C6H11) afforded new dicationic 30-electron triple-decker complexes [(-C5H5)Co(-:-C4H4BCy)ML](BF4)2 containing a cyclohexyl-substituted borole ligand in the central position.  相似文献   

14.
The viscosities of dilute solutions of a number of tetraalkylammonium and alkali metal halides, tetraphenylarsonium chloride, sodium tetraphenylborate, and tetrabutylammonium tetrabutylborate, as well as several nonelectrolytes have been measured in the high dielectric constant solvent N-methylacetamide (NMA) at 35 and 55°C. The relative viscosities were fitted to the extended Jones-Dole equation, = 1 + AC1/2 + BC + DC2. The pattern of behavior of the B coefficients is roughly similar to that observed in H2O. However, the small ions have exceptionally large B values in this solvent due to strong solvation effects, while the large organic ions do not display the sharp crossing of the Einstein law, B=2.5 V, characteristic in H2O of hydrophobic interaction. The D coefficients roughly parallel the B behavior and display remarkably regular ionic trends. This suggests that they arise largely from hydrodynamic origins. Nonelectrolytes have small or negative B coefficients showing that the Einstein law is not applicable at the molecular level and that nonelectrolytes are poor models for structurally similar ions. A simple mixture law is presented as an alternative to the Einstein law to explain the B coefficients.  相似文献   

15.
FTIR spectra have been studied for staircase cyclopentadienyl complexes containing two or three metal carbonyl fragments bound by the metal-carbon bond Cp(CO)2Fe-CpmMn(CO)3 (1), Cp(CO)2Fe-CpmFe(CO)2CH2Ph (2), Cp(CO)2Fe-Cpm(CO)2Fe-CpmMn(CO)3 (3), Cp(CO)2Mo-Cpm(CO)2Fe-CpmMn(CO)3 (4), Cp(CO)3W-Cpm(CO)2Fe-CpmMn(CO)3 (5), Cp(CO)2Fe-Cpm(CO)2Fe-BmCr(CO)3 (6), Cr(CO)3Bm-CpmFe(CO)2CH2Ph (7), where Cp = 5-C5H5, Cpm = 15-C5H4, Bm = 16-C6H5. Temperature-dependent FTIR spectra were measured inn-pentane solutions over a wide temperature range and in the low-temperature solid matrices of argon and nitrogen. Rotamers, formed due to rotation about the metal-carbon -bond, were found in solutions and matrices. A molecular mechanics calculation of1 proved the possibility of such rotation.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1952–1956, November, 1994.The authors are grateful to the Russian Foundation for Basic Research (project code No 93-03-18592) and to the International Science Foundation (project code No MEQ000).  相似文献   

16.
Summary Reactions between -Cp2V and PX3 (X=Cl, Br or I) yield the corresponding dihalogenated derivatives -Cp2VX2 (X=Cl, Br or I). The oxidative addition of ICl and IBr to -Cp2V gives mixed halogenated derivatives -Cp2VIX (X=Cl or Br). All the compounds have been characterized by elemental analyses, magnetic moment measurements and i.r. and e.p.r. spectra.  相似文献   

17.
The ruthenium arene complexes [(-arene)Ru(-9-SMe2-7,8-C2B9H10)]+ (arene = C6H6 (3a); arene = 1,3,5-C6H3Me3 (3b)) with the monoanionic carborane ligand were synthesized by the reactions of the [9-SMe2-7,8-C2B9H10] anion with [(-arene)RuCl2]2. The structure of the compound [3a]BPh4 was established by single-crystal X-ray diffraction analysis.  相似文献   

18.
Summary -(5:5-Fulvalene)-di--hydrido-bis(5-cyclopentadienyltitanium) (1) can be prepared by the reduction of Cp2TiCl2 with LiAlH4 in methylbenzenes and in tetralin at their boiling temperatures in yields greater than 90%. The reduction proceedsvia the bis(5-cyclopentadienyl)titanium(III) chloride dimer which is further transformed into the unstable [Cp2TiH] species. Thermal decomposition of the latter accompanied by hydrogen evolution gives rise to (1). -(5:5-Fulvalene)--hydrido--chloro-bis(5-cyclopentadienyltitanium), the first fulvalene containing compound observed in the system is formed by hydrido-chloro exchange of (1) with (Cp2TiCl)2 and aluminium chlorohydrides.  相似文献   

19.
The reactions of 8-amino-2,4-dimethylquinoline (L) (1) with polynuclear nickel(ii) and cobalt(ii) hydroxotrimethylacetato complexes under anaerobic conditions were studied. The nonanuclear cluster Ni9(4-OH)3(3-OH)3(n-OOCCMe3)12(HOOCCMe3)4 gave the mononuclear complex Ni(2-L)(2-OOCCMe3)2 (2). The tetranuclear complex Ni4(3-OH)2(-OOCCMe3)4(2-OOCCMe3)2(EtOH)6 produced the mononuclear complex Ni(2-L)(2-OOCCMe3)(OOCCMe3)L (3). At room temperature, the cobalt-containing polynuclear trimethylacetates, viz., the polymer [Co(OH) n (OOCCMe3)2–n ] x and the tetranuclear complex Co4(3-OH)2(-OOCCMe3)4(2-OOCCMe3)2(EtOH)6, were transformed into the trinuclear cobalt(ii) complex Co3(3-OH)(-OOCCMe3)4(2-L)2(OOCCMe3) (4). Meanwhile, at 80 °C these compounds generated the binuclear cobalt(iii) complex Co2(22-(HN)C9NMe2)2(-OOCCMe3)(L)(OOCCMe3)3 (5). The structures of the resulting compounds were established by X-ray diffraction analysis. Compounds 24 exhibit the antiferromagnetic spin-spin exchange coupling, whereas compound 5 is diamagnetic.  相似文献   

20.
Redox properties of mono- and binuclear -complexes of Cr with fluoranthene with the composition of (6-C16H10)Cr(6-C6H6), (6-C16H10)Cr(CO)3 and (-6,6-C16H10)Cr2(6-C6H6)(CO)3 are studied by cyclic voltammetry. Relations between half-wave potentials of redox processes and coordination sites of fragments Cr(6-C6H6)- and Cr(CO)3 with the ligand and their nature are found.  相似文献   

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