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1.
We study here the reactions between C 60 and planar C 5H 5+ cations that lead to the formation of [C 60C 5H 5] + adduct cations in the chemical ionization source of the mass spectrometer. The structures, stabilities and charge locations of some possible isomers of [C 60C 5H 5] +: 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 C 5H 5+ cyclopentadienium cation seems to be an “inverted umbrella” sitting on a five-membered ring of the C 60 cage. 相似文献
2.
LnCl 3 (Ln=Nd, Gd) reacts with C 5H 9C 5H 4Na (or K 2C 8H 8) in THF (C 5H 9C 5H 4 = cyclopentylcyclopentadienyl) in the ratio of 1 : to give (C 5H 9C 5H 4)LnCl 2(THF) n (orC 8H 8)LnCl 2(THF) n], which further reacts with K 2C 8H 8 (or C 5H 9C 5H 4Na) in THF to form the litle complexes. If Ln=Nd the complex (C 8H 8)Nd(C 5H 9C 5H 4)(THF) 2 (a) was obtained: when Ln=Gd the 1 : 1 complex [(C 8H 8)Gd(C %H 9)(THF)][(C 8H 8)Gd(C 5H 9H 4)(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B 3LYP/6-311G(d,p)密度泛函方法对B 2H 5+阳离子和B 2H 5·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,B 2H 5+单态有2种稳定的几何构型(D 3h,C 1),其中C 1构型是新发现的.B 2H 5+三重态阳离子除已知C s构型外,又发现两种稳定构型(C 1).对于B 2H 5·自由基体系,共有4种异构体(包括两种新发现的构型C s),其中,具有单桥结构的C 2v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B 2H 5+单态的C 2v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B 2H 5-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C 2v和C s两种稳定构型,而三重态只有C 2v一种稳定构型. 相似文献
4.
The infrared spectra of solid samples of C 4H 7K and C 4D 7K have been investigated in the 4000 to 30 cm −1 range. A complete assignment of intramolecular fundamentals of C 4H 7− and C 4D 7− ions and of potassium-allyl vibrations is proposed and the intramolecular force constants are calculated. The C(CH 2) 32− anion has been identified spectroscopically. Structures of C 3H 5−, C 4H 7− and C(CH 3) 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 (C 5R 5)M(μ-CO) 3RuC 5Me 5 (M = Cr, Mo, W; R = Me, Et) has been prepared in good yields by the reaction of [C 5R 5M(CO) 3] − with [C 5Me 5Ru(CH 3CN) 3] +. (C 5Me 4Et)W(μ-CO) 3Ru(C 5Me 5) 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 C 5R 5M-units. Using [CpRu(CH 3CN) 3] + or [CpRu(CO) 2(CH 3CN)] + as the cationic precursor leads to the formation of dimetallic species (C 5R 5)M(CO) 5RuC 5H 5 with both bridging and terminal carbonyl groups. 相似文献
6.
The dimethylphosphino substituted cyclopentadienyl precursor compounds [M(C 5Me 4CH 2PMe 2)], where M=Li + (1), Na + (2), or K + (3), and [Li(C 5H 4CR′ 2PMe 2)], where R′ 2=Me 2 (4), or (CH 2) 5 (5), [HC 5Me 4CH 2PMe 2H]X, where X −=Cl − (6) or PF 6− (7) and [HC 5Me 4CH 2PMe 2] (8), are described. They have been used to prepare new metallocene compounds, of which representative examples are [Fe(η-C 5R 4CR′ 2PMe 2) 2], where R=Me, R′=H (9); R=H and R′ 2=Me 2 (10), or (CH 2) 5 (11), [Fe(η-C 5H 4CMe 2PMe 3) 2]I 2 (12), [Fe{η-C 5Me 4CH 2P(O)Me 2} 2] (13), [Zr(η-C 5R 4CR′ 2PMe 2) 2Cl 2], where R=H, R′=Me (14), or R=Me, R′=H (15), [Hf(η-C 5H 4CMe 2PMe 2) 2]Cl 2] (16), [Zr(η-C 5H 4CMe 2PMe 2) 2Me 2] (17), {[Zr(η-C 5Me 4CH 2PMe 2) 2]Cl}{(C 6F 5) 3BClB(C 6F 5) 3} (18), [Zr{(η-C 5Me 4CH 2PMe 2) 2Cl 2}PtI 2] (19), [Mn(η-C 5Me 4CH 2PMe 2) 2] (20), [Mn{(η-C 5Me 4CH 2PMe 2B(C 6F 5) 3} 2] (21), [Pb(η-C 5H 4CMe 2PMe 2) 2] (23), [Sn(η-C 5H 4CMe 2PMe 2) 2] (24), [Pb{η-C 5H 4CMe 2PMe 2B(C 6F 5) 3} 2] (25), [Pb(η-C 5H 4CMe 2PMe 2) 2PtI 2] (26), [Rh(η-C 5Me 4CH 2PMe 2)(C 2H 4)] 29, [M(η,κ P-C 5Me 4CH 2PMe 2)I 2], where M=Rh (30), or Ir, (31). 相似文献
7.
Rate constants for the tunneling reaction (HD + D → h + D 2) 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 (C 6H 6− + C 2H 5OH → C 6H 7 + C 2H 5O −) in solid ethanol, the tunneling elimination of H 2 molecule of H 2 molecule ((CH 3) 2 CHCH(CH 3) 2+ → (CH 3) 2 C = C(CH 3) 2+ + H 2) in solid 2,3-dimethylbutane, and the selective tunneling reaction of H atoms in solid neo-C 5H 12-alkane mixtures. 相似文献
8.
Introduction Succinateion (C4H4O4) 2 -(—OOCCH2 CH2 COO— )isaversatileligandsinceeachofthefourterminalcarboxyloxygensisabletoparticipateincoordinationtocentralmetalatom(s)inadditiontotheflexibilityoftheC—Cbone .Suchcoordinatingversatilityhasbeenreflectedinseve… 相似文献
9.
Reaction of optically active ketone complexes (+)-( R)-[(η 5-C 5H 5)Re(NO)-(PPh 3)(η 1-O=C(R)(CH 3)] + BF 4− (R = CH 2CH 3, CH(CH 3) 2m C(CH 3) 3, C 6H 5) with K(s-C 4H 9) 3BH gives alkoxide complexes (+)-( RS)-(η 5-C 5H 5)Re(NO)(PPh 3)-(OCH(R)CH 3) (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, (CH 3) 3P, each with H 2O, HCl and HF together with DFT calculations on up to three sets of reaction products of substituted phosphonium cations, (CH 3) 3P–R +. These products comprise (a) P(III) normal complexes (CH 3) 3PHY, (b) P(IV) ‘reverse’ complexes Y(H–CH 2) 3P–R, (c) P(IV) ylidic complexes YHCH 2(CH 3) 2P–R and (d) P(V) covalent compounds Y–P(CH 3) 3–R for Y=HO, Cl and F and R=H, CH 3, C 2H 5, C 2H 4OH and C 2H 4OC:OCH 3. 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=CH 3, C 2H 5, C 2H 4OH and C 2H 4OC:OCH 3. 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---(C 6H 4-2-SMe) with R=C 6H 5 or 2,4,6-Me 3-C 6H 2 with palladium(II) salts is reported. These studies have allowed us to prepare and characterize the coordination complexes: cis-[Pd{R---CH=N---(C 6H 4-2-SMe)}Cl 2] {R=C 6H 5 or 2,4,6-Me 3-C 6H 2} and the cyclopalladated compounds [Pd{C 6H 4---CH=N---(C 6H 4-2-SMe)}Cl] and [Pd{(2-CH 2-4,6-Me 2-C 6H 2)---CH=N---(C 6H 4-2-SMe)}Cl]. The X-ray crystal structures of the latter complexes reveal that the thioimines act as a [Csp 2, phenyl,N,S] − and as a [Csp 3, N,S] − terdentate group, respectively. The study of the reactions of the cyclopalladated compounds with PPh 3 is also reported. 相似文献
12.
Liquid crystalline 4-XC 6H 4N=NC 6H 4X-4′ [X = C 4H 9 (1a), C 1OH 21 (1b), OC 4H 9 (1c), OC 8H 17(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-C 4H 9OC 6H 4N=NC 6H 4OC 4H 9-4′)] (2) and [Ag(OC1O 3)L 2] [L = 4-XC 6H 4N=NC 6H 4X-4′; X = OC 4H, (3a), OC 8H 17 (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 = C 6H 3(N=NC 6H 4X-4′)-2, X-5; X = C 4H 9 (bpap) (4a), C 10H 21 (dpap) (4b)] while dialkoxyazobenzenes 1c–d require [Hg (OOCCF 3) 2] to obtain [Hg(R)Cl] [R = C 6H 3(N---NC 6H 4X-4′)-2, X-5; X = OC 4H 9 (bxpap) (4c), OC 8H 17 (4d)]. 4a-c react with NaI to give [HgR 2] [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 [Me 4N] [AuCl 4] in the presence of [Me 4N]Cl to give [Au(η 2-R)Cl 2] [R = bpap (6a), bxpap (6b)]. After reaction of [AuCl 3(tht)] (tht = tetrahydrothiophene) with [Me 4N]Cl and 4b (1:2:1), [Me 4N][Au(dpap)Cl 3] (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, (C 10H 10M) 2?(M=Ni, Pd, Pt) derivatives were theoretically investigated. (C 10H 10M) 2?-Iso1, which has two 6-membered rings(6MRs) connected by the M spiro atom, is a 14π-aromatic as a whole plane. (C 10H 10M) 2?-Iso2 has one 6π-aromatic 5MR and one 10π-aromatic 7MR connected by the spiro atom. The free (C 10H 10M) 2? dianions could not exist due to their rather high frontier orbital energies, while the neutral (C 10H 10M)Li 2 compounds are extremely stable against dissociation. Since (C 10H 10M)Li 2 coumponds are not fully coordinated, they trend to form (C 10H 10M)Li 42+ dications, or even[(C 10H 10M)Li 2] n polymers. Arguably, (C 10H 10M) 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 [Zn 2(S 2CTR) 4] (T = 2,5-disubstituted thiophene, R = C 4H 9 (1), C 6H 13 (2), C 8H 17 (3), C 12H 25 (4) and C 16H 33 (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 − C 2H 5) + fragment ion of sec-butyl methyl ether (following electron ionization), and also with the (M − OCH 3) + 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 [ 2H 3]-methanol or [ 2H 4]-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-W 2Cl 2(NMe 2) 4 in hydrocarbon solvents affords the compounds W 2R 2(NMe 2) 4, where R = allyl and 1− and 2-methyl-allyl. In the solid state the molecular structure of W 2(C 3H 5) 2(NMe 2) 4 has C2 symmetry with bridging allyl ligands and terminal W---NMe 2 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 W 2(C 3H 5) 2(NH 2) 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 (π 3). 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 W 2(C 4H 7) 2(NMe 2) 4 in the solid state reveals a gauche-W 2C 2N 4 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-d 8) 1H and 13C NMR spectra over a temperature range −80°C to +60°C indicate that both anti- and gauche- W 2C 2N 4 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 η 3-bound intermediate. The 1-methyl-allyl derivative also binds in an η 1 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 W 2(C 3H 5) 2(NMe 2) 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 W 2(η 3-C 3H 5) 2(NMe 2) 4. The compound W 2R 2(NMe 2) 4 where R = 2,4-dimethyl- pentadiene was similarly prepared and displayed dynamic NMR behaviour explainable in terms of facile η 1 = η 3 interconversions. 相似文献
17.
CpCo(CO) 2 is oxidised by [Cp 2Fe]BF 4 (Cp = C 5H 5) in the presence of neutral ligands L to give the dications [CpCoL 3] 2+ (L = SMe 2, S(n-C 4H 9) 2, PMe 3, C 5H 5N, MeCN; Me = CH 3). In [CpCo(SMe 2) 3] 2+, sulfane ligands are substituted by neutral ligands L, L---L and L---L---L, to give the complexes [CpCoL 3] 2+ (L = SeMe 2, TeMe 2, PMe 3, P(OMe) 3, AsMe 3, SbMe 3, t-C 4H 9NC, C 5H 5N, MeCN), [Cp-Co(L---L)SMe 2] 2+ (L---L = R 2P(CH 2) nPR 2, n = 1, 2, R = C 6H 5; bipyridine, o-phenanthroline, neocuproin) and [CpCo(L---L---L)] 2+ (L---L---L = RP(CH 2CH 2PR 2) 2, R = C 6H 5). The dications react with iodide resulting in the monocations [CpCoL 2I] + and [CpCo(L---L)I] +. Azacobaltocinium cations [CpCo(C 4R 2H 2N)] + (R = H, CH 3) are obtained by reaction of [CpCo(SMe 2) 3] 2+ with metal pyrrolides. 相似文献
18.
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.
(C 5H 5) 2Lu(μ-Cl 2)Na(dme) 2 reacts with LiSi(CH 3) 3 in dimethoxyethane with formation of [Li(dme) 3][(C 5H 5) 2Lu(Si(CH 3) 3) 2]. The crystal structure study shows the compound to consist of discrete ions [Li(dme) 3] + and [(C 5H 5) 2Lu(Si(CH 3) 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) Å 3. 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 (C 6H 16N) 4[Eu 2(MBDA) 4] 2.3C 4H 10O·4C 2H 3N(1-Eu)[H 2MBDA=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 Eu 3+ ions(Φ overall=15%). Upon the addition of different metal ions(i. e., Ag +, Cd 2+, Zn 2+, Fe 3+, Al 3+ and Ni 2+) to the CH 3CN solution of compound 1-Eu, the emission intensities of Eu 3+ ions at 612 nm were affected to some extent, which could be attributed to the presence of ion exchanges between Eu 3+ ions and the metals ions, and the result was confirmed by ESI-TOF mass spectrometry. 相似文献
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