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1.
We study here the reactions between C60 and planar C5H5+ cations that lead to the formation of [C60C5H5]+ adduct cations in the chemical ionization source of the mass spectrometer. The structures, stabilities and charge locations of some possible isomers of [C60C5H5]+: σ-adduct, π-complex, [1,4]- and [l,2]-addition cations, are studied by AM1 semiempirical molecular orbital calculations. We find that the most stable is the σ-addition cation. Another interesting and stable structure is the π-complex cation which is bonded by the electrostatic interaction at the inter-ring distance of 1.589 Å with the C5v symmetry. The C5H5+ cyclopentadienium cation seems to be an “inverted umbrella” sitting on a five-membered ring of the C60 cage.  相似文献   

2.
LnCl3 (Ln=Nd, Gd) reacts with C5H9C5H4Na (or K2C8H8) in THF (C5H9C5H4 = cyclopentylcyclopentadienyl) in the ratio of 1 : to give (C5H9C5H4)LnCl2(THF)n (orC8H8)LnCl2(THF)n], which further reacts with K2C8H8 (or C5H9C5H4Na) in THF to form the litle complexes. If Ln=Nd the complex (C8H8)Nd(C5H9C5H4)(THF)2 (a) was obtained: when Ln=Gd the 1 : 1 complex [(C8H8)Gd(C%H9)(THF)][(C8H8)Gd(C5H9H4)(THF)2] (b) was obtained in crystalline form.

The crystal structure analysis shows that in (C8H8)Ln(C5H9C5H4)(THF)2 (Ln=Nd or Gd), the Cyclopentylcyclopentadieny (η5), cyclooctatetraenyl (η8) and two oxygen atoms from THF are coordinated to Nd3+ (or Gd3+) with coordination number 10.

The centroid of the cyclopentadienyl ring (Cp′) in C5H9C5H4 group, cyclooctatetraenyl centroid (COTL) and two oxygens (THF) form a twisted tetrahedron around Nd3+ (or Gd3+). In (C8H8)Gd(C5H9C5H4)(THF), the cyclopentyl-cyclopentadienyl (η5), cyclooctatetraenyl (η8) and one oxygen atom are coordinated to Gd3+ with the coordination number of 9 and Cp′, COT and oxygen atom form a triangular plane around Gd3+, which is almost in the plane (dev. -0.0144 Å).  相似文献   


3.
用B3LYP/6-311G(d,p)密度泛函方法对B2H5+阳离子和B2H5·自由基的几何异构体的空间构型进行了优化,并在此基础上用QCISD(T)/6-311++G(3df,2p)偶合簇法进行了单点能计算和零点能校正.结果表明,B2H5+单态有2种稳定的几何构型(D3h,C1),其中C1构型是新发现的.B2H5+三重态阳离子除已知Cs构型外,又发现两种稳定构型(C1).对于B2H5·自由基体系,共有4种异构体(包括两种新发现的构型Cs),其中,具有单桥结构的C2v最稳定.用二级多体微扰理论和密度泛函方法对前人所认为稳定的B2H5+单态的C2v构型进行了全优化,结果发现该构型始终具有一个虚频,不是稳定构型.对B2H5-阴离子体系的单态和三重态进行的全优化,理论上得出单态时具有C2v和Cs两种稳定构型,而三重态只有C2v一种稳定构型.  相似文献   

4.
The infrared spectra of solid samples of C4H7K and C4D7K have been investigated in the 4000 to 30 cm−1 range. A complete assignment of intramolecular fundamentals of C4H7 and C4D7 ions and of potassium-allyl vibrations is proposed and the intramolecular force constants are calculated. The C(CH2)32− anion has been identified spectroscopically. Structures of C3H5, C4H7 and C(CH3)32− are discussed and compared with those optimised by the MINDO/3 method.  相似文献   

5.
A series of heterodimetallic complexes of general formula (C5R5)M(μ-CO)3RuC5Me5 (M = Cr, Mo, W; R = Me, Et) has been prepared in good yields by the reaction of [C5R5M(CO)3] with [C5Me5Ru(CH3CN)3]+. (C5Me4Et)W(μ-CO)3Ru(C5Me5) 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 C5R5M-units. Using [CpRu(CH3CN)3]+ or [CpRu(CO)2(CH3CN)]+ as the cationic precursor leads to the formation of dimetallic species (C5R5)M(CO)5RuC5H5 with both bridging and terminal carbonyl groups.  相似文献   

6.
The dimethylphosphino substituted cyclopentadienyl precursor compounds [M(C5Me4CH2PMe2)], where M=Li+ (1), Na+ (2), or K+ (3), and [Li(C5H4CR′2PMe2)], where R′2=Me2 (4), or (CH2)5 (5), [HC5Me4CH2PMe2H]X, where X=Cl (6) or PF6 (7) and [HC5Me4CH2PMe2] (8), are described. They have been used to prepare new metallocene compounds, of which representative examples are [Fe(η-C5R4CR′2PMe2)2], where R=Me, R′=H (9); R=H and R′2=Me2 (10), or (CH2)5 (11), [Fe(η-C5H4CMe2PMe3)2]I2 (12), [Fe{η-C5Me4CH2P(O)Me2}2] (13), [Zr(η-C5R4CR′2PMe2)2Cl2], where R=H, R′=Me (14), or R=Me, R′=H (15), [Hf(η-C5H4CMe2PMe2)2]Cl2] (16), [Zr(η-C5H4CMe2PMe2)2Me2] (17), {[Zr(η-C5Me4CH2PMe2)2]Cl}{(C6F5)3BClB(C6F5)3} (18), [Zr{(η-C5Me4CH2PMe2)2Cl2}PtI2] (19), [Mn(η-C5Me4CH2PMe2)2] (20), [Mn{(η-C5Me4CH2PMe2B(C6F5)3}2] (21), [Pb(η-C5H4CMe2PMe2)2] (23), [Sn(η-C5H4CMe2PMe2)2] (24), [Pb{η-C5H4CMe2PMe2B(C6F5)3}2] (25), [Pb(η-C5H4CMe2PMe2)2PtI2] (26), [Rh(η-C5Me4CH2PMe2)(C2H4)] 29, [M(η,κP-C5Me4CH2PMe2)I2], where M=Rh (30), or Ir, (31).  相似文献   

7.
Rate constants for the tunneling reaction (HD + D → h + D2) in solid HD increase steeply with increasing temperature above 5 K, while they are almost constant below 4.2 K. The apparent activation energy for the tunneling reaction above 5 K is 95 K, which is consistent with the energy (91–112 K) for vacancy formation in solid hydrogen. The results above 5 K were explained by the model that the tunneling reaction was accelerated by a local motion of hydrogen molecules and hydrogen atoms. The model of the tunneling reaction assisted by the local motion of the reactans and products was applied to the temperature dependence of the proton-transfer tunneling reaction (C6H6 + C2H5OH → C6H7 + C2H5O) in solid ethanol, the tunneling elimination of H2 molecule of H2 molecule ((CH3)2 CHCH(CH3)2+ → (CH3)2 C = C(CH3)2+ + H2) in solid 2,3-dimethylbutane, and the selective tunneling reaction of H atoms in solid neo-C5H12-alkane mixtures.  相似文献   

8.
Synthesis and Characterization of Zinc Succinate, Zn(C4H4O4)   总被引:3,自引:0,他引:3  
Introduction  Succinateion (C4H4O4) 2 -(—OOCCH2 CH2 COO— )isaversatileligandsinceeachofthefourterminalcarboxyloxygensisabletoparticipateincoordinationtocentralmetalatom(s)inadditiontotheflexibilityoftheC—Cbone .Suchcoordinatingversatilityhasbeenreflectedinseve…  相似文献   

9.
Reaction of optically active ketone complexes (+)-(R)-[(η5-C5H5)Re(NO)-(PPh3)(η1-O=C(R)(CH3)]+ BF4 (R = CH2CH3, CH(CH3)2m C(CH3)3, C6H5) with K(s-C4H9)3BH gives alkoxide complexes (+)-(RS)-(η5-C5H5)Re(NO)(PPh3)-(OCH(R)CH3) (73–90%) in 80–98% de. The alkoxide ligand is then converted to Mosher esters (93–99%) of 79–98% de.  相似文献   

10.
Theoretical calculations (DFT, MP2) are reported for up to four sets of reaction products of trimethylphosphine, (CH3)3P, each with H2O, HCl and HF together with DFT calculations on up to three sets of reaction products of substituted phosphonium cations, (CH3)3P–R+. These products comprise (a) P(III) normal complexes (CH3)3PHY, (b) P(IV) ‘reverse’ complexes Y(H–CH2)3P–R, (c) P(IV) ylidic complexes YHCH2(CH3)2P–R and (d) P(V) covalent compounds Y–P(CH3)3–R for Y=HO, Cl and F and R=H, CH3, C2H5, C2H4OH and C2H4OC:OCH3. Calculations are carried out at the B3LYP/6-31+G(d,p) level in all cases and also at the MP2/6-31+G(d,p) level for systems in which R=H. Minimum energy structures are determined for predicted complexes or structures and geometrical properties, harmonic vibrations and BSSE corrected binding energies are reported and compared with the limited experimental information available. Potential energy scans predict equilibria between covalent trigonal bipyramidal P(V) forms and reverse complexes comprising hydrogen bonded or ion pair, tetrahedral P(IV) forms separated by low potential energy barriers. Similar scans are also reported for equilibria between reverse complexes and ylidic complexes for Y=OH and R=CH3, C2H5, C2H4OH and C2H4OC:OCH3. Corrected binding energies, structures and values of harmonic modes are discussed in relation to bonding The names ‘pholine’ and ‘acetylpholine’ are suggested for phosphorus analogues to choline and acetylcholine.  相似文献   

11.
The study of the reactivity of R---CH=N---(C6H4-2-SMe) with R=C6H5 or 2,4,6-Me3-C6H2 with palladium(II) salts is reported. These studies have allowed us to prepare and characterize the coordination complexes: cis-[Pd{R---CH=N---(C6H4-2-SMe)}Cl2] {R=C6H5 or 2,4,6-Me3-C6H2} and the cyclopalladated compounds [Pd{C6H4---CH=N---(C6H4-2-SMe)}Cl] and [Pd{(2-CH2-4,6-Me2-C6H2)---CH=N---(C6H4-2-SMe)}Cl]. The X-ray crystal structures of the latter complexes reveal that the thioimines act as a [Csp2, phenyl,N,S] and as a [Csp3, N,S] terdentate group, respectively. The study of the reactions of the cyclopalladated compounds with PPh3 is also reported.  相似文献   

12.
Liquid crystalline 4-XC6H4N=NC6H4X-4′ [X = C4H9 (1a), C1OH21 (1b), OC4H9 (1c), OC8H17(1d)] can be easily prepared in high yields from the corresponding anilines. In order to study the influence of metals on the thermal properties of these materials, we have obtained adducts [AuCl 3(4-C4H9OC6H4N=NC6H4OC4H9-4′)] (2) and [Ag(OC1O3)L2] [L = 4-XC6H4N=NC6H4X-4′; X = OC4H, (3a), OC8H17 (3b)]. The silver adducts show themotropic behaviour. Mercuriation of dialkylazobenzenes 1a-b takes place with [Hg(OAc)2] and LiCl to give [Hg(R)Cl] [R = C6H3(N=NC6H4X-4′)-2, X-5; X = C4H9 (bpap) (4a), C10H21 (dpap) (4b)] while dialkoxyazobenzenes 1c–d require [Hg (OOCCF3)2] to obtain [Hg(R)Cl] [R = C6H3(N---NC6H4X-4′)-2, X-5; X = OC4H9 (bxpap) (4c), OC 8H17 (4d)]. 4a-c react with NaI to give [HgR2] [R= bpap (5a), dpap (5b), bxpap (5c), oxpap (5d)l. Both chloroaryl-, 4a and 4c, and diaryl-mercurials, 5a and 5c, act readily as transmetailating agents towards [Me4N] [AuCl4] in the presence of [Me4N]Cl to give [Au(η2-R)Cl2] [R = bpap (6a), bxpap (6b)]. After reaction of [AuCl 3(tht)] (tht = tetrahydrothiophene) with [Me4N]Cl and 4b (1:2:1), [Me4N][Au(dpap)Cl3] (7) can be isolated. C---H activati bxpap (8b)]. None of the complexes 4–8 shows mesomorphic behaviour.  相似文献   

13.
Aiming to identify the spiro metallaaromatic systems with potential application value, (C10H10M)2?(M=Ni, Pd, Pt) derivatives were theoretically investigated. (C10H10M)2?-Iso1, which has two 6-membered rings(6MRs) connected by the M spiro atom, is a 14π-aromatic as a whole plane. (C10H10M)2?-Iso2 has one 6π-aromatic 5MR and one 10π-aromatic 7MR connected by the spiro atom. The free (C10H10M)2? dianions could not exist due to their rather high frontier orbital energies, while the neutral (C10H10M)Li2 compounds are extremely stable against dissociation. Since (C10H10M)Li2 coumponds are not fully coordinated, they trend to form (C10H10M)Li42+ dications, or even[(C10H10M)Li2]n polymers. Arguably, (C10H10M)2? planes are not the only examples for spiro metallaaromaticity, their derivatives are also potential material building blocks.  相似文献   

14.
The complexes [Zn2(S2CTR)4] (T = 2,5-disubstituted thiophene, R = C4H9 (1), C6H13 (2), C8H17 (3), C12H25 (4) and C16H33 (5)) have been synthesized and their structural features investigated. Compared to the analogous dithiobenzoate complexes, the crystal structure determination of 2 revealed that the thiophene induces a “step-rod” chain pattern instead of the linear, rodlike structure found for the corresponding dithiobenzoates. Complexes 1–5 did not display mesophases under thermal conditions, but an irregular melting pattern was observed for 3 and 4.  相似文献   

15.
Protonated acetaldehyde is methylated on the oxygen during interaction with methanol in the gas phase. The ionic product of the ion/molecule reaction between methanol and protonated acetaldehyde is identical with C-protonated methylvinyl ether (high-pressure ionization), and with the (M − C2H5)+ fragment ion of sec-butyl methyl ether (following electron ionization), and also with the (M − OCH3)+ fragment ion of acetaldehyde dimethylacetal (following electron ionization). The structures of these ions and the mechanism of their formation were established by isotope-labeling experiments and collision-induced dissociation mass spectra of model compounds obtained with three different types of tandem mass spectrometers (BEQQ, triple-quadrupole, and a penta-quadrupole instrument). Gas phase synthesis of the product ion from [2H3]-methanol or [2H4]-acetaldehyde provided insight into its mode of formation and collision-induced dissociation.  相似文献   

16.
The reaction between RMgCl (two equivalents) and 1,2-W2Cl2(NMe2)4 in hydrocarbon solvents affords the compounds W2R2(NMe2)4, where R = allyl and 1− and 2-methyl-allyl. In the solid state the molecular structure of W2(C3H5)2(NMe2)4 has C2 symmetry with bridging allyl ligands and terminal W---NMe2 ligands. The W---W distance 2.480(1) Å and the C---C distances, 1.47(1) Å, imply an extensive mixing of the allyl π-MOs with the WW π-MOs, and this is supported by an MO calculation on the molecule W2(C3H5)2(NH2)4 employing the method of Fenske and Hall. The most notable interaction is the ability of the (WW)6+ centre to donate to the allyl π*-MO (π3). This interaction is largely responsible for the long W---W distance, as well as the long C---C distances, in the allyl ligand. The structure of the 2-methyl-allyl derivative W2(C4H7)2(NMe2)4 in the solid state reveals a gauche-W2C2N4 core with W---W = 2.286(1) Å and W---C = 2.18(1) Å, typical of WW and W---C triple and single bonds, respectively. In solution (toluene-d8) 1H and 13C NMR spectra over a temperature range −80°C to +60°C indicate that both anti- and gauche- W2C2N4 rotamers are present for the 2-methyl-allyl derivative. In addition, there is a facile fluxional process that equilibrates both ends of the 2-methyl-allyl ligand on the NMR time-scale. This process leads to a coalescence at 100°C and is believed to take place via an η3-bound intermediate. The 1-methyl-allyl derivative also binds in an η1 fashion in solution and temperature-dependent rotations about the W---N, W---C and C=C bonds are frozen out at low temperatures. The spectra of the allyl compound W2(C3H5)2(NMe2)4 revealed the presence of two isomers in solution—one of which can be readily reconciled with the presence of the bridging isomer found in the solid state while the other is proposed to be W23-C3H5)2(NMe2)4. The compound W2R2(NMe2)4 where R = 2,4-dimethyl- pentadiene was similarly prepared and displayed dynamic NMR behaviour explainable in terms of facile η1 = η3 interconversions.  相似文献   

17.
CpCo(CO)2 is oxidised by [Cp2Fe]BF4 (Cp = C5H5) in the presence of neutral ligands L to give the dications [CpCoL3]2+ (L = SMe2, S(n-C4H9)2, PMe3, C5H5N, MeCN; Me = CH3). In [CpCo(SMe2)3]2+, sulfane ligands are substituted by neutral ligands L, L---L and L---L---L, to give the complexes [CpCoL3]2+ (L = SeMe2, TeMe2, PMe3, P(OMe)3, AsMe3, SbMe3, t-C4H9NC, C5H5N, MeCN), [Cp-Co(L---L)SMe2]2+ (L---L = R2P(CH2)nPR2, n = 1, 2, R = C6H5; bipyridine, o-phenanthroline, neocuproin) and [CpCo(L---L---L)]2+ (L---L---L = RP(CH2CH2PR2)2, R = C6H5). The dications react with iodide resulting in the monocations [CpCoL2I]+ and [CpCo(L---L)I]+. Azacobaltocinium cations [CpCo(C4R2H2N)]+ (R = H, CH3) are obtained by reaction of [CpCo(SMe2)3]2+ with metal pyrrolides.  相似文献   

18.
半乳糖醇与氯化稀土配合物的合成及荧光光谱研究   总被引:4,自引:1,他引:3  
测定了半乳糖醇铽配合物的晶体结构.结果表明,糖的羟基和水分子同时与稀土离子配位,糖的羟基、水分子及氯离子之间形成广泛的氢键网络.红外光谱结果表明,铕和铽对半乳糖醇具有相同的配位方式.本文还测定了荧光光谱,得到稀土离子的特征光谱.  相似文献   

19.
(C5H5)2Lu(μ-Cl2)Na(dme)2 reacts with LiSi(CH3)3 in dimethoxyethane with formation of [Li(dme)3][(C5H5)2Lu(Si(CH3)3)2]. The crystal structure study shows the compound to consist of discrete ions [Li(dme)3]+ and [(C5H5)2Lu(Si(CH3)3)2]. The compound crystallizes in the space group P2/n with a 14.497(5) b 9.041(2), c 14.672(6) Å, β 103.85(3)° and V 1867(2) Å3. The crystal and molecular structure was refined to R = 0.0473 for 2491 observed reflections with Fo 3σ(Fo).  相似文献   

20.
Herein, we reported the synthesis and investigation of highly luminescent quadruple-stranded helicate (C6H16N)4[Eu2(MBDA)4]2.3C4H10O·4C2H3N(1-Eu)[H2MBDA=N-methyl-4,4'-bis(4,4,4-trifluoro-1,3-dioxobutyl)di- phenylamine] for its stability toward metal ions in the solution. The material was characterized via X-ray crystallographic technique, Fourier transform infrared(FTIR) spectroscopy and electrospray ionization quadrupole time-of- flight(ESI-TOF) mass spectrometry. The results on the luminescence quantum yields clearly demonstrate that the ligand can effectively sensitize the luminescence of the Eu3+ ions(Φoverall=15%). Upon the addition of different metal ions(i. e., Ag+, Cd2+, Zn2+, Fe3+, Al3+ and Ni2+) to the CH3CN solution of compound 1-Eu, the emission intensities of Eu3+ ions at 612 nm were affected to some extent, which could be attributed to the presence of ion exchanges between Eu3+ ions and the metals ions, and the result was confirmed by ESI-TOF mass spectrometry.  相似文献   

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