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1.
The cyclopentadienylchromium carbonyl thiocarbonyls Cp2Cr2(CS)2(CO)n (n = 4, 3, 2, 1) have been studied by density functional theory using the B3LYP and BP86 functionals. The lowest energy Cp2Cr2(CS)2(CO)4 structure can be derived from the experimentally characterized unbridged Cp2Cr2(CO)6 structure by replacing the two terminal carbonyl groups furthest from the Cr-Cr bond with two terminal CS groups. The two lowest energy Cp2Cr2(CS)2(CO)3 structures have a single four-electron donor η2-μ-CS group and a formal Cr-Cr single bond of length ∼3.1 Å. In contrast to the carbonyl analogue Cp2Cr2(CO)5 these Cp2Cr2(CS)2(CO)3 structures are viable with respect to disproportionation into Cp2Cr2(CS)2(CO)4 and Cp2Cr2(CS)2(CO)2 and thus are promising synthetic targets. The lowest energy Cp2Cr2(CS)2(CO)2 structures have all two-electron donor CO and CS groups and short CrCr distances around ∼2.3 Å suggesting the formal triple bonds required to give the chromium atoms the favored 18-electron configurations. These Cp2Cr2(CS)2(CO)2 structures are closely related to the known structure for Cp2Cr2(CO)4. In addition, several doubly bridged structures with four-electron donor η2-μ-CS bridges are found for Cp2Cr2(CS)2(CO)2 at higher energies. The global minimum Cp2Cr2(CS)2(CO) structure is a triply bridged triplet with a CrCr triple bond (2.299 Å by BP86). A higher energy singlet Cp2Cr2(CS)2(CO) structure has a shorter Cr-Cr distance of 2.197 Å (BP86) suggesting the formal quadruple bond required to give each chromium atom the favored 18-electron configuration.  相似文献   

2.
With copper(I) iodide as catalyst, σ-alkynyls, compounds (η5-C5H5)Cr(NO)2(CC-C6H5) (5), [(η5-C5H4)-COOCH3]Cr(NO)2(CC-C6H5) (10), and [(η5-C5H4)-COOCH3]W(CO)3(CC-C6H5) (13), were prepared from their corresponding metal chloride 1, 6 and 12. Structures of compound 3, 5 and 12 have been solved by X-ray diffraction studies. In the case of 5, there is an internal mirror plane passing through the phenylethynyl ligand and bisecting the Cp ring. The phenyl group is oriented perpendicularly to the Cp with an eclipsed conformation. The twist angle is 0° and 118.4° for -CC-Ph and two NO ligands, respectively. The orientation is rationalized in terms of orbital overlap between ψ3 of Cp, dπ of Cr atom, and π of alkynyl ligand, and complemented by molecular orbital calculation. The opposite correlation was observed on the chemical shift assignments of C(2)-C(5) on Cp ring in compounds 6 and 12, using HetCOR NMR spectroscopy. The electron density distribution in the cyclopentadienyl ring is discussed on the basis of 13C NMR data and compared with the calculations via density functional B3LYP correlation-exchange method.  相似文献   

3.
The reaction of with p-CH3C6H4S(O)2O(CH2)3C6H5 produces (η5-C5H5)(OC)3Mo(CH2)3C6H5. This is only the second structurally characterized organometallic species in which an aromatic moiety is separated by three or more methylene groups. The alkyl chain adopts a staggered conformation, the Mo-C(1)-C(2)-C(3)-C(4) unit is nearly coplanar, and the alkyl chain eclipses the trans-carbonyl group on Mo. NMR evidence indicates that this conformation is preserved in solution.  相似文献   

4.
由侧链带有噻吩的环戊二烯基配体C5H5C6H10C4H3S与Fe(CO)5在二甲苯中加热回流,合成了1个新颖的四羰基二铁配合物[(η5-C5H4)C6H10(C4H3S)Fe(CO)2]2。通过元素分析、IR、1H NMR对其结构进行了表征,用X-射线单晶衍射确定了其结构。X-射线单晶衍射表明配合物中有2个桥羰基和2个端羰基,Fe-Fe的键长为0.25465(10)nm。  相似文献   

5.
合成了新型配合物{(n-Bu)2Sn[(η5-C5H5)Fe(η5-C5H4)COO]2}2,用元素分析、红外光谱和核磁共振谱( 1H、13C、119Sn)进行了表征,并用X-射线单晶衍射分析法测定其晶体结构。晶体属单斜晶系,空间群P21/c,晶胞参数a=11.753(4)?,b=21.133(7)?,c=23.374(9)?,β=101.62(3)°,V=5687(4)?3Z=4,Dc=1.614Mg·m-3,μ(MoKα)=1.912mm-1F(000)=2800,最终可靠因子R1=0.0827,wR2=0.2085。配合物分子呈中心对称,是具有Sn2O2中心内环的二聚体结构;每个锡原子与5个O原子和2个C原子形成扭曲的五角双锥几何构型,其中5个O原子为赤道配位原子,而C-Sn-C为配合物的轴。  相似文献   

6.
The crystal structure of the Os3(μ,η2-O=CC6H5)(η3-C3H5)(CO)9 cluster synthesized by the reaction of the (μ-H)Os3(μ-O=CC6H5)(CO)10 complex with allylamine in chloroform was determined by X-ray analysis. Prolonged storage of the reaction mixture led to N-C bond cleavage in allylamine and η3-addition of the allyl fragment at one of the Os atoms (Os-C 2.246 ?, 2.248 ?, and 2.273 ?). The unit cell parameters of the complex are a = 9.494(1) ?, b = 10.479(1) ?, c = 12.474(2) ?, α = 84.55(1)°, β = 70.08(1)°, γ = 70.72(1)°, V = 1255.8(4), ?3, space group P , Z = 2; C19H10O10Os3; d calc = 2.922 g/cm3, 3085 I hkl > 2σ I of 3611 collected reflections; R = 0.0252. The structure of Os3(μ,η2-O=CC6H5)(η3-C3H5)(CO)9 is molecular. The plane of the Os3 triangle and the OsCOOs plane are connected according to the “butterfly” principle with an angle of 103.4° between them. The Os-Os distances in the cluster core vary from 2.836(1) ? to 2.844(1) ?; the Os-Ccarb distances are 1.88(1)–1.97(1) ?; the distances to the atoms of the bridging ligands are Os-C 2.11(1) ?, Os-O 2.14(1) ?; the O-C bridging bond is 1.24(1) ?. of the Os3(μ,η2-O=CC6H5)(η3-C3H5)(CO)9 triosmium cluster were studied theoretically. The potential curve of the internal rotation of the allyl ligand relative to the Os(1)-C(9) bond was determined. The rotation barrier of the allyl ligand in crystal relative to the Os(1)-C(9) bond is 8.38 kJ/mol, and the rotation of the ligand is not hindered. The effects of the intra-and intermolecular interactions on the conformation state of the cluster complex are considered. Original Russian Text Copyright ? 2008 by V. A. Maksakov, N. V. Pervukhina, N. V. Podberezskaya, M. Yu. Afonin, V. A. Potemkin, and V. P. Kirin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 5, pp. 926–932, September–October, 2008.  相似文献   

7.
The reactivity of [Ru3Mo(μ42-CC)(μ-CO)3(CO)2(η-C5H4R)3(η-C5H5)] (R = H; Me) have been investigated, initially to elucidate the nature of the starting material, and, latterly, to define the reactivity of an interesting ethane-1,2-bis(ylidyne) species. While the mixed RuMo clusters were unreactive towards simple electrophiles and carbonyl substitution by phosphine ligands they did react with atmospheric oxygen or carbon monoxide to give substantially different products. In all instances oxygen was incorporated either at the metal centre or at the C2 fragment. High-pressure carbonylations yielded [Ru3(μ-CO)3(η-C5H5)33-C-C(O)O{Ru(CO)2(η-C5H5)})] and [{Ru2(μ-CO)(CO)2(η-C5H4Me)2}(μ42-CC){Ru(CO)(η-C5H4Me)Mo(η-C5H5)(=O)(μ-O)}], an ethane-1,2-bis(ylidene) complex, this exemplifying a relatively rare raft geometry which further reacted with Cl2CCCl2 to give [Mo34-C2(Ru(CO)2(η-C5H4Me))(CO)(μ-CO)(η-C5H5)3(Cl)2] having a similar geometry and undergone halogenation. In order to extend the extant examples of these raft clusters we explored the reaction of [{Ru(CO)2(η-C5H4R)2}2(μ-C2)] with [{Ru(CO)2(η-C5H5)2}2] to provide a rational synthetic pathway leading to very reactive [Ru(μ42-CC)(μ2-CO)2(CO)4(η-C5H4Me)2(η-C5H4R)2] rafts.  相似文献   

8.
The structure and dynamic behavior of complex [(η5-C5H4CH3)Cr(CO)2(μ-SBu)Pt(PPh3)2] in solution was studied by multinuclear (1H, 13C, 31P) NMR spectroscopy including a phase-sensitive NOESY experiment. Increasing temperature causes rupture of the Cr-Pt bond in the three-membered ring of the complex and rotation of the S-Pt(PPh3)2 unit around the Cr-S bond line, followed by formation of a new Cr-Pt bond to close the ring. All activation parameters for this dynamic process have been determined.  相似文献   

9.
The new ferrocenylmethylphosphines PH(CH2Fc)2 (1) [Fc = Fe(η5-C5H5)(η5-C5H4)] and P(CH2Fc)3 (2) and the phosphonium salt [P(CH2Fc)3(CH2OH)]I (3) were synthesised from P(CH2OH)3 and [FcCH2NMe3]I. [P(CH2Fc)(CH2OH)3]Cl (4) was obtained from P(CH2Fc)(CH2OH)2, CH2O and HCl. The new phosphines and phosphonium salts were fully characterised by NMR and IR spectroscopy and MS. [Mo(CO)6] reacts with 1 to give [Mo(CO)5{PH(CH2Fc)2}] (5) in high yield, but attempts to employ 2 as a ligand failed. The reaction of [P(CH2Fc)3(CH2OH)]I (3) and [PH(CH2Fc)3]I (obtained in situ from 3 and Na2S2O5) with [WI2(CO)3(NCMe)2] gave the complex salts [P(CH2Fc)3(CH2OH)][WI3(CO)4] (6) and [PH(CH2Fc)3][WI3(CO)4] (7), respectively. [P(CH2Fc)4]I (8) was synthesized from PH2CH2Fc and [FcCH2NMe3]I. Crystal structures were obtained for 1, 3-8.  相似文献   

10.
[Ce(NO3)5H2O]·(C3H5N2)2的合成、晶体结构及热分析   总被引:2,自引:0,他引:2  
Colorless crystal, [Ce(NO3)5H2O]·(C3N2H5)2, has been obtained from the reaction of Ce(NO3)3 with imdazole in the aqueous solution and its crystal structure has been determined by single crystal X-ray diffraction techniques.The crystal belongs to triclinic, space group P1. The cell parameters are: a = 0.7489(1) um, b = 0.7914(2) nm, c = 1.8139(3) nm, a = 89.39(2)°, β = 89.37(l) °,γ = 63.18(2)°, Dc = 2.1g·cm-3, Z = 2, R = 0.0319.In the compound, all of five nitrates are bidentate and one molecule of water is monodentate, the coordination number of Ce (Ⅲ) is 11.The processes of thermal decomposition of the compound was proposed by its TGcurve.  相似文献   

11.
Mononuclear compounds M(CO)23-C3H5)(en)(X) (X = Br, M = Mo(1), W(2); X = N3, M = Mo(3), W(4); X = CN, M = Mo(5), W(6)) and cyanide-bridged bimetallic compounds [(en)(η3-C3H5)(CO)2M(μ-CN)M(CO)23-C3H5)(en)]Br (M = Mo (7), W(8)) were prepared and characterized. These compounds are fluxional and display broad unresolved proton NMR signals at room temperature. Compounds 1-6 were characterized by NMR spectroscopy at −60 °C, which revealed isomers in solution. The major isomers of 1-4 adopt an asymmetric endo-conformation, while those of 5 and 6 were both found to possess a symmetric endo-conformation. The single crystal X-ray structures of 1-6 are consistent with the structures of the major isomer in solution at low temperature. In contrast to mononuclear terminal cyanide compounds 5 and 6, cyanide-bridged compounds 7 and 8 were found to adopt the asymmetric endo-conformation in the solid state.  相似文献   

12.
Bromination/nitrosylation of [η5-(carbomethoxy)cyclopentadienyl]dicarbonylnitrosylchromium (8) (hereafter called carbomethoxycynichrodene) with hydrogen bromide/isoamyl nitrite gives bromo [η5-(carboxymethoxy)cyclopentadienyl]dinitrosylchromium (10) in 84%. Compounds 15 in 74% and 16 in 90% were obtained from the corresponding cynichrodene derivatives via the same method. Compounds [η5-(carbomethoxy)cyclopentadienyl](isothiocyanato)dinitrosylchromium (13) and [η5-(carbomethoxy)cyclopentadienyl](isoselenocyanato)dinitrosylchromium (14) were prepared from [η5-(carbomethoxy)cyclopentadienyl]chlorodinitrosylchromium (9) with excess potassium thiocyanate and selenocyanate, respectively, after detaching the chloride by the action of silver nitrate. One of the nitrosyl groups in each compound is located at the site away from the exocyclic carbonyl carbon of the Cp(Cr) ring with twist angles of 168.5° and 172.3°, respectively. The chemical shifts of C(2)-C(5) carbon atoms of a series of substituted-cyclopentadienyldinitrosylchromium derivatives, [η5-(C5H4-sub)]Cr(NO)2X, have been assigned using two-dimensional HetCOR NMR spectroscopy. The assigned chemical shifts were compared with the NMR data of their analogues of ferrocene, and the opposite correlation on the assignments was observed. The electron density distribution in the cyclopentadienyl ring is discussed on the basis of 13C NMR data and those of 10 and 13 are compared with the calculations via density functional B3LYP correlation-exchange method.  相似文献   

13.
The title complex Cu[C5H3N(CCH3=N-C6H5)2]2(PF6)2 has been synthesized by reaction of Schiff base C5H3N(CCH3=N-C6H5)2 and cupric sulfate in toluene solution. The crystal structure was determined by X-ray diffraction method and the chemical formula weight of the complex is 1041.85. The crystal structure belongs to triclinic system with space group P1 and cell parameters: a=12.6470(10)?, b=14.123(2)?, c=15.613(2)?;α=66.150(10)°,β=79.470(10)°,γ=78.290(10)°, V=2481.6(5)?3, Z=2, Dc=1.394Mg·m-3 and F(000)=1064. The final R[I >2σ(I)]:R1=0.0668, wR2=0.1927; R(all data): R1=0.1133, wR2=0.2357. The Cu(Ⅱ) was coordinated by six nitrogen, at the same time the Cu(Ⅱ) formed a distorted octahedron, besides the angles and planes of this compound were discussed . The result of kinetics of the thermal decomposition indicated that the first step of it is 2 series chemical reactions, the function of machanism is f(a)=(1-a)2, and the activation energy is 144.64E/kJ. CCDC: 180872.  相似文献   

14.
cis-(η5-MeC5H4)W(CO)2P(OiPr)3I (1) was converted to the trans isomer 2 in the solid state (90-110 °C). The reaction was monitored by heating 1 in NMR tubes for periods of time (2-60 min), cooling the tubes to room temperature and determining the conversion by solution 31P and 1H NMR spectroscopy. The data were consistent with a first-order reaction and yielded an activation energy of 59 ± 3 kJ mol−1. Comparative kinetic data were obtained from an in situ analysis of a powder-XRD study of 1. The powder-XRD study was conducted at 80-100 °C (10-60 min), yielding an activation energy of 52 ± 2 kJ mol−1 (first-order reaction). The reaction could not be monitored by single crystal X-ray diffraction as the crystal disintegrated over time on heating. This disintegration process was monitored by optical microscopy and revealed that while the bulk crystal morphology was retained the crystal surface roughened with time. The compounds 1 and 2 were also structurally characterised by X-ray crystallographic techniques.  相似文献   

15.
为获得适中乙烯基含量的液体聚丁二烯为目的, 对Co(naph)2-Al2(C2H5)3Cl3-P(OPh)3催化体系进行了较为系统的研究, 考察了该体系的催化剂配比、浓度及供电子试剂对分子量、微观结构和转化率的影响. 实验结果表明, 该体系在一定的条件下可以制备出分子量在700~3500、1,2结构含量在35%~40%且转化率高于55%的液体聚丁二烯.  相似文献   

16.
0 引言 稀土是一类具有特殊结构和性质的元素,稀土元素不仅大量用于工业,而且在农业和医学领域也有广泛应用 [1,2].其中,镧系离子以其独特的光、电、磁、催化和分析等性能而受到人们的广泛关注,并进行了大量的研究.镧系离子本身发光效率低,目前,设计并合成含有稀土离子La3+和Eu3+的超分子配合物,作为发光分子器件和荧光探针成为稀土配位化学,材料科学,超分子化学,分析化学和生物化学等研究领域的热点课题之一 [3~8].但对它们的热化学行为的研究鲜见文献报道.  相似文献   

17.
用Co2(CO)8分别与两个杂环配体C(S)NHP(S)(C6H4OCH3)OC(Ph)CH (L1)和C(S)NHC(CH3)2P(S)(Cl)N(Ph) (L2)反应,合成两个新的三核钴羰基硫簇合物Co3(CO)73-S)[μ,η2-CNP(S)(C6H4OCH3)OC(Ph)CH]()和Co3(CO)73-S)[μ,η2-SCNC(CH3)2P(S)(Cl)N(Ph)]()。用元素分析,IR, 1H NMR, 31P NMR及MS谱表征了它们的结构,同时用X射线衍射法测定了它们的晶体分子结构,二者属于三斜晶系,空间群P1,的晶胞参数为:a=0.84768(1)nm,b=1.19049(3)nm,c=1.43639(1)nm,α=86.926(1)°,β=81.601(3)°,γ=88.535(2)°,V=1.4318(5)nm3,Z=2,Dc=1.641g·cm-3,F(000)=716,μ=1.893mm-1,R=0.0602,Rw=0.1515。的晶胞参数为:a=1.2050(2)nm,b=1.2448(2)nm,c=0.8951(2)nm,α=97.49(1)°,β=93.552(4)°,γ=108.432(3)°,V=1.2554(3)nm3,Z=2,Dc=1.841g·cm-3,F(000)=690,μ=2.419mm-1,R=0.0423,Rw=0.1075。的分子骨架Co3S为三角锥构型,S作为面桥基配体,所有CO作为端基配体与三个Co原子成键。中含有CoCoCN四元环组件,中含有CoCoSCN五元环组件。  相似文献   

18.
The title complex Ni3(C14H8N3O5)2(C5H5N)4 has been synthesized by the reaction of 2-hydroxy-N′-(4-nitrobenzoyl)benzohydraizide with nickel acetate in pyridine solution. Its molecular structure was characterized by elemental analysis, IR spectra and X-ray crystal structure determination. Crystal data for this compound: Mono-clinic, space group P21/c, Mr=1 089.00, a=0.249 27(5) nm, b=0.161 40(3) nm, c=0.121 81(2) nm, β=94.59(3)°, V=4.885 2(17) nm3, Z=4, Dc=1.481 Mg·m-3, F(000)=2 232, R1=0.049 7, wR2=0.106 8 (observed reflections with I>2σ(I)) and R1=0.105 1, wR2=0.119 4 (all reflections), GOF=1.021. The complex was evaluated for their antitumor activi-ties against two kinds of cell lines (K562 and BGC) by MTT method. A preliminary bioactivity study indicates that the complex shows distinct antitumor activity. CCDC: 627252.  相似文献   

19.
The complex Ru44-S)(μ,η3-C3H5)2(CO)12 is prepared and examined by IR and NMR spectroscopy; its crystal structure is determined (an automatic Bruker-Nonius X8 Apex four-circle diffractometer equipped with a 2-D CCD-detector, 100 K, graphite-monochromated molybdenum source, λ = 0.71073 ?). The crystal belongs to the orthorhombic crystal system with unit cell parameters a = 19.3781(9) ?, b = 12.2898(7) ?, c = 10.1726(4) ?, V = 2422.6(2) ?3, space group Pnma, Z = 4, composition C18H10O12Ru4S, d x = 2.343 g/cm3. The molecule of point symmetry C 1 is situated on the mirror plane of the space group Pnma, two carbonyl groups at Ru2 and Ru3 atoms overlapping with the allylic ligand with a weight of 50% so that carbon atoms coincide. Thus, we have a racemic structure with two overlapping enantiomers of the molecule of Ru44-S)(μ,η3-C3H5)2(CO)12. Original Russian Text Copyright ? 2008 by I. Yu. Prikhod’ko, V. P. Kirin, V. A. Maksakov, A. V. Virovets, and A. V. Golovin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 4, pp. 748–752, May–June, 2008.  相似文献   

20.
Equimolar reactions of molybdenum hexacarbonyl with tris(piperidino)phosphine (L1), bis(morpholino)(phenyl)phosphine (L2), and (Di-isopropylamino)(morpholino)(phenyl) phosphine (L3), which are examples of symmetrically and unsymmetrically substituted tertiary(amino)phosphines, afford the corresponding mono derivatives, Mo[P(NC5H10)3)](CO)5 (1), Mo[P(Ph)(NC4H8O)2](CO)5 (2), and Mo[P(Ph){N(i-C3H7)2}(NC4H8O)](CO)5 (3) in moderate yields as air stable crystalline solids. In the case of L1, some amount of trans-bis derivative, Mo[P(NC5H10)3)]2(CO)4 (4), was also isolated. X-ray structures of 1, 2, and 3 have been determined. Compounds 1 and 2 crystallize in the monoclinic system with space group P21/c, while 3 crystallizes in the triclinic system with space group Pī. While the Mo-P and Mo-Cax bond distances in these complexes are comparable with those of other P-C bonded phosphines, the presence of chiral phosphine seems to induce a relatively weaker interaction with the molybdenum center. Intermolecular hydrogen bonding is seen in compound 1.  相似文献   

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