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1.
《Polyhedron》1987,6(8):1703-1705
The acetone complex [Fe(CO)2(Me2CO)(η5-C5H5)][PF6] reacts with L (L = H2NNHCSNH2, cy-C5H10CNNHCSNH2, or R′R″CNNHCSNH2 where R′ = R″ = Me; R′ = H, R″ = Ph; R′ = H, R″ = p-NO2Ph; R′ = p-MePh) in refluxing trichloromethane to give the new complexes [Fe(CO)2L(η5-C5H5)][PF6]. The complexes are clearly coordinated through the sulphur atom since the thiosemicarbazide complex reacts with benzaldehyde to afford the corresponding thiosemicarbazone compound.  相似文献   

2.
The absolute integrated i.r. intensities of the CO and CS stretching bands of the thiocarbonyl complexes (η6C6H5R)Cr(CO)2(CS), where R = H, Me, Cl and CO2Me, have been determined in CS2 solutions. The intensities have been correlated with each other and with the band wavenumbers, and have been shown to be dependent on the nature of the substituent R in the aromatic ring. The intensities have been demonstrated to be better probes of the electronic effects occurring in these complexes than are the wavenumbers, and correlate well with the Hammett substituent parameters, σ0.  相似文献   

3.
The synthesis, IR spectra, and the temperatures of the transition into a ferromagnetic state (T c) of layered ferromagnetics [R3RX[MCr(C2O4)3 (M = Mn, Fe, Co, Cu, and Ni) with the [Ph3BuP]+, [Bu3RN]+ (R = Pr, Et, and Me) cations capable of subsequently changing the distances between metallooxalate layers have been considered. The temperatureT c has been found to be independent of the size of the organic cation. It is believed that the determining factors in the transition to a ferromagnetic state are exchange interactions inside the metallooxalate layer.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2327–2330, September, 1996.  相似文献   

4.
Introduction  Asarelativelynewmemberofnaturalalkaloidswith2 ,6 disubstituted 3 piperidinolskeleton ,irnigaine 1wasisolatedfromthetubersofArisarumVulgare (Araceae)in1995byMelhaouiandBode .1Itsstructureandrelativeconfigurationswereelucidatedby1HNMRstudiesandtheabsoluteconfigurationwasproposedonthebasisofitsopti calrotation .1Soonafterthen ,Meyerandhisco workersreportedthefirstsynthesisof (- ) (2R ,3R ,6S) irni gaineandtheconfigurationconfirmation .Althoughtheirsynthesisroutewasshortan…  相似文献   

5.
One-pot oxidation of R3Sb (R=Ph, Me, Cl, or C6F5) withtert-butyl hydroperoxide in the presence of 1,2-diols and monodentate donor compounds was studied. The structures of the resulting neutral organic donor-acceptor SbV complexes, Ph3(C6H4O2)Sb…OSMe2, Ph3(C6H4O2)Sb…ONC5H5, Me3(C6H4O2)Sb…ONC5H5, Me3(C6H4O2)Sb…NC5H5, Ph3(C2H4O2)Sb…ONC5H5, and Cl(C6F5)2(C2H4O2)Sb…OPPh3, were established by X-ray diffraction analysis. In these complexes, the coordination environment about the Sb atoms is a distorted octahedron. The Sb?O(N) distances and the Sb?O?E angles (E=S, N, or P) vary over wide ranges.  相似文献   

6.
The photo-induced decarbonylation of CpCr(NO)(CO)2 (1a) in MeCN solution in the presence of R2E2 (E = S, Se; R = Me, Ph) leads to the formation of chalcogenolato-bridged binuclear complexes Cp2Cr2(NO)2(-ER)2 [E = S; R = Me (2a), Ph (3a); E = Se, R = Me (4a), Ph (5a)] while reactions between CpM(NO)(CO)2 [M = Mo (1b), W (1c)] and Ph2E2 (E = S, Se) result in mononuclear complexes CpM(NO)(EPh)2 [M = Mo; E = S (9b), Se (10b); M = W, E = S (11c), Se (12c)]. The corresponding reactions of (1b) with Me2E2 (E = S, Se) yielded both mono and binuclear complexes: CpMo(NO)(SeMe)2 (8b), Cp2Mo2(NO)2(-EMe)2 [E = S (6b), Se (7b)]. The new complexes have been characterized by i.r., 1H-, 13C-n.m.r. spectra and by electron-impact mass spectrometry.  相似文献   

7.
The reaction of pentaphenylantimony and the oxime HON=CRR taken in 1 : 1 molar ratio in toluene gave tetraphenylantimony oximates Ph4SbON=CRR (CRR = C6H9–C6H9-2 (I) and R = Ph, R = C(O)Ph (II)). According to X-ray diffraction data, the Sb atoms in I and II have a distorted trigonal-bipyramidal coordination with oximate ligands in the axial positions. The CaxSbO angles are 177.6(1)° in I and 176.58(6)° in II. The Sb–C bond lengths lie in the ranges of 2.120(4)–2.203(4) Å for I and 2.122(2)–2.181(2) Å for II. The Sb–O bond lengths are 2.120(2) Å (I) and 2.166(1) Å (II). The lengths of the intramolecular Sb···N contacts are 2.806(3) and 2.918(2) Å in I and II, respectively.  相似文献   

8.
The heterobimetallic cyclosiloxanolate sandwich clusters Na[6-cyclo (PhSiO2)6]2[Fe(OR)]2Ni4(6-Cl) (R = H, Me) (1) were prepared from Na2[(PhSiO2)6]2Na4Ni4(OH)2 in the form of solvates. The new clusters 1 were characterized by spectra (UV-VIS, IR, 1H-NMR), cyclic voltammetry. conductivity, magnetic susceptibility, and single-crystal X-ray diffraction.  相似文献   

9.
The preparation and comprehensive characterization of a series of homoleptic sandwich complexes containing diphosphacyclobutadiene ligands are reported. Compounds [K([18]crown-6)(thf)(2)][Fe(η(4)-P(2)C(2)tBu(2))(2)] (K1), [K([18]crown-6)(thf)(2)][Co(η(4)-P(2)C(2)tBu(2))(2)] (K2), and [K([18]crown-6)(thf)(2)][Co(η(4)-P(2)C(2)Ad(2))(2)] (K3, Ad = adamantyl) were obtained from reactions of [K([18]crown-6)(thf)(2)][M(η(4)-C(14)H(10))(2)] (M = Fe, Co) with tBuC[triple bond]P (1, 2), or with AdC[triple bond]P (3). Neutral sandwiches [M(η(4)-P(2)C(2)tBu(2))(2)] (4: M = Fe 5: M = Co) were obtained by oxidizing 1 and 2 with [Cp(2)Fe]PF(6). Cyclic voltammetry and spectro-electrochemistry indicate that the two [M(η(4)-P(2)C(2)tBu(2))(2)](-)/[M(η(4)-P(2)C(2)tBu(2))(2)] moieties can be reversibly interconverted by one electron oxidation and reduction, respectively. Complexes 1-5 were characterized by multinuclear NMR, EPR (1 and 5), UV/Vis, and M?ssbauer spectroscopies (1 and 4), mass spectrometry (4 and 5), and microanalysis (1-3). The molecular structures of 1-5 were determined by using X-ray crystallography. Essentially D(2d)-symmetric structures were found for all five complexes, which show the two 1,3-diphosphacyclobutadiene rings in a staggered orientation. Density functional theory calculations revealed the importance of covalent metal-ligand π bonding in 1-5. Possible oxidation state assignments for the metal ions are discussed.  相似文献   

10.
利用稀土元素独特的光、电特性,成功地制备出稀土掺杂的CuIn1-xRxTe2(R=稀土)(CIRT)新型光伏半导体材料。应用X射线衍射、扫描电镜、拉曼散射等进行了相关的晶体结构、显微组织、光性能研究。研究表明:稀土元素的掺杂能够稳定黄铜矿型的晶体结构,点阵常数随稀土元素的掺杂呈现出涨落性。应用Rietveld方法测定原子占位,稀土元素部分替代In占据4b晶位。稀土元素的掺杂导致晶粒团聚现象,并形成柱状或层状单晶颗粒,具有透光性。CuInTe2和CuIn0.9Sm0.1Te2的Eg值分别为1.25和1.32 eV,这表明:CuIn0.9Sm0.1Te2与CuIn1-xGaxTe2具有接近的禁带宽度,适宜做光伏材料。拉曼散射实验证实:稀土元素的添加对于光散射诱发的原子振动频率有较大的影响,使得一些原有频率消失,有助于光谱频段的选择性吸收。  相似文献   

11.
The preparation and characterization of two new mixed-valence, trinuclear species, [Mn3O(O2CCF3)6(H2O)3]CF3COOH4/3H2O (1) and [Mn3O(O2CCF3)6(CH3COOH)3] (2), is reported. Compound 1 crystallizes in the triclinic space group, P¯1 (No. 2), with the parameters, a=12.3131(9) Å, b=12.4427(9) Å, c=12.965(1) Å, =72.593(4)°, =73.453(5)°, =68.345(4)°, V=1727.2(2) Å3, and Z=2. A total of 14060 reflections were collected in the range 1.6827.52°. The final weighted and non-weighted agreement indices, R1=0.0589 and wR2=0.1445 were based on a total of 6953 unique reflections with an R int value of 0.0542. Compound 2 crystallizes in the monoclinic space group, P21/n (No. 14), with the parameters, a=12.876(3) Å, b=12.212(4) Å, c=17.732(4) Å, =100.40(3)°, V=3640.4(1) Å3, and Z=4. A total of 32197 reflections were collected in the range 1.7227.13°. The final weighted and non-weighted agreement factors, R1=0.0647 and wR2=0.1609 were based on a total of 8018 unique reflections with an R int value of 0.0462. An investigation of the physical properties revealed that both compounds display an intermediate ground state of S=3/2 as a consequence of intramolecular antiferromagnetic coupling. The magnetic data for compound 1 was best fit to the parameters g=2.09, J=–5.5 cm–1, J=–3.4 cm–1, and D Mn(III)=–4.5 cm–1; the data for compound 2 was best fit to the parameters g=2.10, J=–2.9 cm–1, J=–5.5 cm–1, and D Mn(III)=–4.5 cm–1.  相似文献   

12.
INDO方法研究了C70R2(R=OH,CH3)4种异构体的结构和稳定性,表明1,9-C70(OH)2比7,8-C70(OH)2稳定,两者能量差为38.5kJ/mol,而7,8-C70(CH3)2比1,9-C70(CH3)2能量低23.0kJ/mol.以优化构型为基础,对C70R2(R=OH,CH3)的电子光谱进行了理论预测.  相似文献   

13.
李勤瑜  许旋 《物理化学学报》2007,23(12):1875-1880
In order to study the effects of R group on Fe-Hg interactions and 31P chemical shifts, the structures of mononuclear complexes Fe(CO)3(PPh2R)2 (R=pym: 1, fur: 2, py: 3, thi: 4; pym=pyrimidine, fur=furyl, py=pyridine, thi=thiazole) and binuclear complexes [Fe(CO)3(PPh2R)2(HgCl2)] (R=pym: 5, fur: 6, py: 7, thi: 8) were studied by using the density functional theory (DFT) PBE0 method. The 31P chemical shifts were calculated by PBE0-GIAO method. Nature bond orbital (NBO) analyseswere also performed to explain the nature of the Fe-Hg interactions. The conclusions can be drawn as follows: (1) The complexes with nitrogen donor atoms are more stable than those with O or S atoms. The more N atom there are, the higher is the stabilitity of the complex. (2) The Fe-Hg interactions play a dominant role in the stabilities of the complexes. In 5 or 6, there is a σ-bond between Fe and Hg atoms, However, in 7 and 8, the Fe-Hg interations act as σP-Fe→nHg and σC-Fe→nHg delocalization. (3) Through Fe邛Hg interactions, there is charge transfer from R groups towards the P, Fe, and Hg atoms, which increases the electron density on P nucleus in binuclear complexes. As a result, compared with their mononuclear complexes, the 31P chemical shifts in binuclear complexes show some reduction.  相似文献   

14.
采用DFT B3LYP和QCISD方法研究了不饱和类锗烯H2C=GeLiCl与RH(R=F, OH, NH2)的插入反应. 在B3LYP/6-311+G(d,p)水平上优化了反应势能面上的驻点构型. 结果表明, H2C=GeLiCl与HF、H2O 或NH3发生插入反应的机理相同. QCISD/6-311++G(d,p)//B3LYP/6-311+G(d,p)计算的三个反应的势垒分别为173.53、194.48和209.05 kJ·mol-1, 反应热分别为60.18、72.93和75.34 kJ·mol-1. 相同条件下发生插入反应时, 反应活性顺序都是H—F>H—OH>H—NH2.  相似文献   

15.
Photolysis of a benzene solution containing [Fe3(CO)93-E)2] (E=S, Se), [(η5-C5R5)Fe(CO)2(CCRI)] (R=H, Me; RI=Ph, Fc), H2O and Et3N results in formation of new metal clusters [(η5-C5R5)Fe3(CO)63-E)(μ3-ECCH2RI)] (R=H, RI=Ph, E=S 1 or Se 2; R=Me, RI=Ph, E=S 3 or Se 4; R=H, RI=Fc, E=S 5; R=Me, RI=Fc, E=S 6 or Se 7). Reaction of [Fe3(CO)93-S)2]with [(η5-C5R5)Mo(CO)3(CCPh)] (R=H, Me), under same conditions, produces mixed-metal clusters [(η5-C5R5)MoFe2(CO)63-S)(μ-SCCH2Ph)] (R=H 8; R=Me 9). Compounds 19 have been characterised by IR and 1H and 13C-NMR spectroscopy. Structures of 1, 5 and 9 have been established crystallographically. A common feature in all these products is the formation of new C-chalcogen bond to give rise to a (ECCH2RI) ligand.  相似文献   

16.
The geometries, energetics and spectroscopic properties of oxygen clusters, Oxy(x=2~6, y=-2~2), were investigated at the B3LYP/6-311G (d, p) level. The CASSCF calculations were carried out for the ground and excited states of3O2and2O2+. The total energy is3O2(3Σg-)<2O2-(2Πgi)<1O2(1Δg)<1O2-2(1Σg+)<2O2+(2Πg)<1O2+2(1Σg+). The relative energy of the active doublet anion of oxygen molecule,2O2-(2Πgi), is only 28 kJ/mol higher than the triplet neutral oxygen molecule,3O2(3Σg-). The calculated O-O vibrational frequencies all are in good agreement with the experimental values. They are 1577 (1580), 1139 (1090), 1563 (1484), 627 (615~545) and 1993 (1905) cm-1, where the O-O vibrational frequency values in parentheses are experimental values, for3O2(3Σg-),2O2-(2Πgi),1O2(1Δg),1O2-2(1Σg+) and2O2+(2Πg), respectively. Moreover, the O-O vibrational frequency of1O2+2(1Σg+) was computed as 2368 cm-1which has not been reported before at both experimental and theoretical levels. Both bent and linear geometries of O3were studied. The bent-types of O3are more favorable than the linear-type in energy. Three types of structure for oxygen trimers are calculated at the B3LYP/6-311G (d, p) level. They are the structure-I with an obtuse angle of O-O-O,the structure-II with an acute angle of O-O-O, and the structure-III of linear type. For a bent-type structure of O3species (structure-I), the total enegy is2O3-(2B1)<1O3(1A1)<3O3(3B2)<1O3-2(1A1)<2O3+(2A1). The optimization of geometry at B3LYP/6-311G (d, p) level indicated that the species of2O3-(2B1) with 1.3573 of O-O bond length and 115.6584o of O-O-O bond anger is the ground state of O3. The total energy of O4species and their ions is2O4-(Cs,2A′, bend-type)<2O4-(C2v,2A2,face-centered triangle-type)<2O4-(D∞h,2Σg, linear-type)<1O4(Cs,1A′, bend-type)<1O4(D∞h,1Σg, linear-type)<1O4(D4h,1A1g, square-type)<1O4(C2v,1A1, face-centered triangle-type)<2O4-(D4h,1A1g, square-type)<2O4+(D∞h,2Σg, linear-type)<2O4+(Cs,1A′, bend-type). The species with the lowest relative energy is an anion,2O4-(Cs,2A′, bendtype), with chair form geometry and characteristic vibronic frequencies of 1179 and 1349 cm-1. The relative energy of1O5(C2v,1A1) with coplanar-triangle-bicone geometry is the lowest among the O5species and their ions, which may be a resonance structure with1O5(C2v,1A1) of A type. Their characteristic vibronic frequency is 1302 cm-1. The relative energy of the O6species and their ions with hexagon geometry is lower than one with linear geometry. Their infrared vi-bronic intensity may be weak and unobservable but the Raman vibronic intensity may be strong and observable based on their symmetry.  相似文献   

17.
18.
The clusters Fe3(CO)9(RC2 R 1) (R=R 1=Ph, Et; R=Me, R 1=Ph), complexes 1a, 1b, 1c, containing an alkyne bound in perpendicular fashion with respect to a cluster edge, catalyze the hydrogenation of some acetylenes either under homogeneous and solid–gas conditions. We hypothesize that cluster catalysis occurs and that the catalytic activity is related to the coordinating ability of the alkynic substrates. Competition between hydrogenation and formation of metallacyclic byproducts occurs. The new metallacyclic derivatives Fe3(CO)6(-CO)2{(RC2 R 1)(R 2C2 R 3)}, Fe2(CO)6{(RC2 R 1)(R 2C2 R 3)} {R=R 1=Et, R 2=R 3=H, Ph; R 2=Me, R 3=Et, Ph; R 2=H, R 3=Bu t . R=R 1=Ph, R 2=Me, R 3=Et, Ph} (complexes 2, 3) were found both in the homogeneous reaction mixtures and after the solid–gas reactions. The formation of these products lowers the catalytic activity.  相似文献   

19.
Reaction of Fe3(CO)12 and Ph2PH in the presence of Et3N in THF at 0?°C immediately forms Fe2(CO)6(μ-PPh2)(μ-OH) (1), Fe2(CO)6(μ-PPh2)(μ-k2O,P-OPPh2) (2), and Fe2(CO)6(μ-PPh2)2 (3) in yields of 25, 14, and 19%, respectively. Experiments confirm that Et3N shortens the reaction time. The absence of O2 hinders the formation of 2. The presence of H2O can increase the yield of 1. Their structures have been determined by X-ray crystallography and the complexes have been completely characterized by EA, IR, and 1H, 13C, 31P NMR. Electrochemical studies reveal that they exhibit catalytic H2-producing activities.  相似文献   

20.
Two new title compounds have been prepared in powder form. Their spectral data are found to be consistent with the structure foundin Hofmann-Td-type clathrates.  相似文献   

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