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1.
The reaction of ammonium tetrathiometalate (NH4)2[MS4] (M = W or Mo) with the R(+) or S(?) forms of the organic amine α‐methylbenzylamine [PhCH(CH3)NH2] results in the formation of the corresponding non‐centrosymmetric bis(α‐methylbenzylammonium) tetrathiometalate complexes [PhCH(CH3)NH3]2[MS4] (R‐ammonium M = W 1 ; R‐ammonium M = Mo 2 ; S‐ammonium M = W 3 , S‐ammonium M = Mo 4 ) which were characterized by elemental analysis, IR, Raman, UV‐Vis and CD spectra, X‐ray powder diffractometry and single crystal X‐ray crystallography. Compounds 1 ‐ 4 crystallize in the chiral space group P21 and constitute the first examples of structurally characterized chiral organic ammonium group VI tetrathiometalates. The structures of 1 ‐ 4 consist of two crystallographically independent chiral organic ammonium cations and a tetrahedral tetrathiometalate dianion. The N‐H···S and C‐H···S interactions between the anions and cations organise them such that the organic ammonium ions always point towards the S atoms of [MS4]2?.  相似文献   

2.
Reactions of (NH4)2MS4 or (NH4)MOS3 (M = Mo, W) with CuSCN and the closo carborane diphosphine 1,2-(PPh2)2-1,2-C2B10H10 in CH2Cl2 yielded five heterobimetallic trinuclear Mo(W)–Cu–S clusters with the formula Cu2MS4L2 (M = Mo(1), W(3), L = 1,2-(PPh2)2-1,2-C2B10H10), Cu2MoS4L2 · CH2Cl2 (2) and Cu2MOS3L2 (M = Mo(4),W(5)). All the clusters have been characterized by elemental analysis, FT-IR, UV/Visible, 1H and 13C NMR spectroscopy and X-ray structure determination. X-ray crystal structure analysis showed that the metal skeleton of these clusters could be classified into two types. With (NH4)2MS4 (M = Mo, W), the three metal atoms (two Cu atoms and one M atom (M = Mo, W)) are almost in a linear conformation, while with (NH4)2MOS3 the conformation of the heterobimetallic trinuclear cluster core was a butterfly-shaped (or referenced as defective cubane-like with two corners missing). The coordination sphere of the metal atoms in all the clusters, either for Cu or M, should be described as a distorted tetrahedron. For each cluster, the closo carborane diphosphine ligand 1,2-(PPh2)2-1,2-C2B10H10 was introduced into the Cu2MS4 or Cu2MOS3 cluster cores and coordinated bidentately through the P atoms to Cu(I), and this resulted in a stable five-member chelating ring between the bis-diphosphine ligand and the metal.  相似文献   

3.
Four novel M/Cu/S polymers [Et4N][MS4Cu3(S2COEt)2] (1a: M=Mo; 1b: M=W) and Et4N][MS4Cu2SEt] (2a: M=Mo; 2b: M=W) have been prepared by reactions of [Et4N]2[MS4] with CuS2COEt and CuSEt. X-ray crystal structure determinations reveal that the polymeric anions of complexes 1a and 1b both consist of MS4Cu3 building blocks linked via bidentate [S2COEt] bridging ligands to form 1D polymeric chains. The anion structures of the polymeric compounds 2a and 2b contain MS4Cu2 repeating units which are connected via μ-SEt ligands forming a zigzag chain running down the crystallographic b axis.  相似文献   

4.
The electron transfer, i. r., RAMAN and photoelectron spectra and the powder diagrams of Tl2MO2S2, TI2MOS3 Tl2MS4 (M = Mo, W) and, in comparison, the photoelectron spectra of some other transition metal compounds The electron transfer, i. r., RAMAN and photoelectron spectra and the powder diagrams of Tl2MoO2S2, Tl2WO2S2, Tl2MoOS3, Tl2WOS3, Tl2MoS4 and Tl2WS4 are reported and discussed. The different methods allow a discussion of the strong polarising effect of the Tl(I) cation on the anions. For the purpose of comparison the photoelectron spectra of the salts Tl3MX4 (M = V, Nb, Ta; X = S, Se); Tl2MO4 (M = Mo, W); Cs2MX4, (M = Mo, W; X = S, Se) and other similar salts were also measured.  相似文献   

5.
前驱团簇[Et4N]4[MS4Cu4I6](M=Mo (1a); W (1b))与双齿桥连配体1, 2-双(4-吡啶基)乙烷(bpe)在苯胺溶液中反应, 生成2个结构相似的一维[MS4Cu4]团簇基配位聚合物{[MS4Cu4(bpe)2(ani)2I2]·3.5ani}n (M=Mo (2), W (3); ani=苯胺)。通过元素分析、红外光谱和X-射线单晶衍射对23进行了表征。晶体结构分析表明前驱团簇1a1b中五核马鞍形[MS4Cu4]簇核分别在23中得以保留, 2个桥连配体bpe连接相邻的簇核, 在[111]方向延伸形成一维“Z”字形链结构。  相似文献   

6.
Reactions of [NH4]2[MS4](M = Mo,W), CuX(X = Br, I) and PPh3 in the solid state produced four mixed-metal sulfur containing clusters {Cu3MS3X}(PPh3)3S(M = Mo, W; X = Br, I), two of which (1: M = Mo, X = I; 2: M = W, X = Br) were structurally determined. Crystals of 1 and 2 are triclinic, space group P1 (1: a = 11.895(3), b = 13.107(1), c = 20.473(2)Å, α = 74.95(6), β = 84.87(8), γ = 64.27(7)°, Z=2, V=2776.1 Å3, Rw = 0.064 for 6443 observed reflections. 2: a = 11.876 (1), b = 13.065 (2), c = 20.325(2)Å, α = 74.95(1), β= 85.39(1), γ = 64.09(1)°, Z = 2, V = 2737.3Å3, Rw = 0.055 for ·5303 observed reflections). The results of the structure determination showed that the central units of the two cubane-like cluster compounds are composed of four metal atoms and four non-metal atoms situated at alternate corners. The differences of cubane-like cluster compounds obtained from solid state reactions and from solution reactions are discussed.  相似文献   

7.
前驱团簇[Et4N]4[MS4Cu4I6](M=Mo(1a);W(1b))与双齿桥连配体1,2-双(4-吡啶基)乙烷(bpe)在苯胺溶液中反应,生成2个结构相似的一维[MS4Cu4]团簇基配位聚合物{[MS4Cu4(bpe)2(ani)2I2]·3.5ani}n(M=Mo(2),W(3);ani=苯胺)。通过元素分析、红外光谱和X-射线单晶衍射对23进行了表征。晶体结构分析表明前驱团簇1a1b中五核马鞍形[MS4Cu4]簇核分别在23中得以保留,2个桥连配体bpe连接相邻的簇核,在[111]方向延伸形成一维"Z"字形链结构。  相似文献   

8.
Reactions of (NH4)2MS4, AgBr and CuBr in γ-methylpyridine produced one new compound, [MS4Cu4(γ-MePy)8][M6O19] (1, M = W; 2 , M = Mo), of which 1 was characterized by single crystal X-ray analysis. The crystal data: orthorhombic, Pbcn, a = 15.434(4), b = 16.732(2), c = 28.657(7) Å, V = 7400.8(8) Å3, Z = 4 , R = 0.072 for 3121 independent data. The compound is the first example which contains both polyoxotungstate anion and heteropolynuclear cluster cation. In the structure of the cation four edges of the tetrahedral WS2?4 core are coordinated by four copper atoms, giving a WS4Cu4 aggregate of approximate D2h symmetry. The differences between the reaction of Cu+ with MS2?4 and that of Ag+ with MS2?4 in pyridine and its derivatives are discussed.  相似文献   

9.
WS2纳米颗粒的合成及摩擦学性能研究   总被引:4,自引:0,他引:4  
将自制的WO3纳米颗粒前驱体与S粉混合,在自制的反应装置氢气氛中,于550~750 ℃下煅烧得到二硫化钨纳米颗粒,反应中用H2代替H2S以减少对周围环境的污染。该合成路线简单且产物纯度高。用XRD、SEM、TEM和HRTEM对二硫化钨纳米结构进行了表征和分析,并将WS2纳米颗粒作为添加剂添加到N40基础油中,在MS-T3000摩擦磨损仪测试其摩擦学性能。结果显示:制备的二硫化钨颗粒平均粒径在50 nm以内,其形状为球形或类球形。WS2纳米颗粒作为普通润滑油的纳米级固体添加剂表现出了较优异的摩擦学性能。  相似文献   

10.
The reactions of the substituted Group VI metal carbonyls of the type M(CO)4(2-Mepy)2 (M = Mo, w) and M(CO)3(L)3 (L = py, M = Mo, W; L = NH3, M = Mo) with mercuric derivatives HgX2 (X = Cl, CN, SCN) have given rise to three series of tricarbonyl complexes: M(CO)3(py)HgCl2 · 1/2HgCl2 (M = Mo, W); 2[M(CO)3(L)]Hg(CN)·nHg(CN)x (L = py, M = Mo, W, n = 12, × = 2; L = 2- Mepy, × = 1; M = Mo, n = 3; M = W, n = 1); and [M(CO)3(L)Hg(SCN)2 · nHg(SCN)2] (L = py, M = Mo,W, n = 0; L = 2-Mepy, M = Mo, W, n = 12; L = NH3, M = Mo, n = 0) depending on which mercuric compound is employed. All the reactions with Hg(SCN)2 give isolable products whereas those with Hg(CN)2 and HgCl2 did so far only the reactions with [M(CO)4(2-Mepy)2] and M(CO)3(py)3. The greater reactivity of Hg(SCN)2 than of Hg(CN)2 and HgCl2 is consistent with the various acceptor capacities of the groups bonded to the mercury atom.The reactions studied always involve displacement of the N-donor ligand of the original complex and partial or total displacement of the halide or pseudohalide groups of the mercury compound to give in all cases compounds containing MHg bonds. In addition, elimination of a CO group in the tetracarbonyl complexes M(CO)4(2-Mepy)2occurs.  相似文献   

11.
Synthetic, spectroscopic (IR, UV/VIS/NIR, EPR), and electrochemical studies have been carried out for complexes of the type [Co(MO4–nSn)2]2? (M = Mo, W; n = 2, 3, 4) and most of the corresponding trianions [Co(MoO4–nSn)2]3?, which can be obtained from the dianions by reduction. The complexes have delocalized electronic ground states and remarkable metal-ligand interactions, leading to unusual electronic absorption spectra. The electronic structure and the electrochemical properties of the species existing with different electron populations are also discussed in relation to those of other 3 d transition metal thiometallato complexes. The crystal structures of [(Ph3P)2N]2[Et4N][Co(MS4)2] · 2 CH3CN (M = W ( 1 ), Mo ( 2 )) have been determined. The compounds crystallize in the orthorhombic space group P21212 (Z = 2) with unit cell dimensions: a = 1252.6(4), b = 3385.2(7), c = 1077.6(3) for 1 ; a = 1261.0(9), b = 3393.2(28), c = 1084.4(7) pm for 2 . The structure of the anions consists of two tetrahedral MS4 units acting as bidentate ligands to the central Co atoms with significant deviation from idealized D2d symmetry (W? ;Co? ;W = 168.3(2), Mo? ;Co? ;Mo = 169.6(8)°). Averaged interatomic distances (pm) for 1 are as follows (values for 2 in brackets): Co? ;Sbr = 224.4 (219), Co? ;M = 272.7 (275), M? ;Sbr = 223.0 (223), M? ;Sterm = 217.5 (215) pm. Investigations of complex formation in solution, using electronic absorption spectroscopy and cyclic voltammetry, allowed physical data of those species which could not be isolated in crystalline form to be obtained.  相似文献   

12.
Reactions of[NH_4]_2[MS_4](M=Mo,W),AgX(X=Cl,Br,I,CN,SCN)and PPh_3in the solid state produced six new mixed-metal sulfur containing cluster compounds,two ofwhich,{Ag_3MoS_3I}(PPh_3)_3S(1)and{Ag_3WS_3Cl}(PPh_3)_3S·0.5P(S)Ph_3·3H_2O(2),were determinedby single crystal X-ray analysis.The crystal data:1,triclinic,P,a=12.114(2),b=13.420(2),c=20.346(3),α=74.53(1),β=86.73(1),γ=63.74(1)°,Z=2,R=0.043 for 4805 independentdata;2,hexagonal,R3,a=b=16.201(3),c=45.091(10),Z=6,R=0.042 for 2729 independentdata.The central unit{Ag_3MS_3X}(M=Mo,W;X=Cl,I)of the two compounds can be des-cribed as a slightly distorted cube,four corners being formed by the MS_4~(2-) ligand(with a ter-minal S atom).The remaining corners are occupied by one X(Cl or I)atom and three Agatoms(with one PPh_3 ligand bound to each of the latter).The generation of different types ofAg-Mo(W)-S cluster compounds prepared from solid state reactions under different reactiontemperatues is discussed.  相似文献   

13.
本文在研究Mo(W)-Cu(Ag)-S原子簇化合物的低热固态合成化学基础上,详细地对该类簇合物进行了归纳,从中提出;1,MO4-nSn^2^-(M=Mo,W;n=2,3,4)作为配体中心。2,氧原子在簇合物中仅作为端基,不参与同其他金属成键。3,单个MS4(M=Mo,W)基团最多只能键合六个Cu(Ag)原子,即最大核数为七。4,迄今为止所有Mo(W)-Cu-S原子簇化合物中Cu均为+1价。5,预计  相似文献   

14.
Carbon-13 NMR spectral data for complexes having the general formula CpM(CO)nX (Cp = η5-C5H5; M = Mo or W, n = 3; M = Fe, n = 2; X = halogen, methyl or acetyl) and their phosphine and isocyanide substitution products are reported. For CpM(CO)3X complexes two carbonyl resonances (1 : 2 ratio) are observed in all cases, consistent with the retention of the “piano-stool” geometries observed in the solid state. Substituted complexes CpM(CO)2(L)X (M = Mo or W; L = PR3 or cyclohexyl isocyanide) are unequivocally assigned cis or trans geometries on the basis of the number of observed carbonyl resonances and values of 2J(PC) for the phosphine substituted derivatives. Spectral data for [M(CO)5X]? (M = Cr, Mo or W; X = Cl, Br or I) and η7-C7H7Mo(CO)2X and the halide derivatives above generally show an increase in the shielding for carbonyls adjacent to the halide ligand in the order Cl < Br < I. Carbonyl resonances are more shielded in isostructural complexes in the order Cr < Mo < W (triad effect).  相似文献   

15.
Models are proposed for the mixed transition metal-silicon bare clusters CuSi10 and MSi16 (M=Cr, Mo, W) in which the transition metals are located in the centers ofD 4d silicon polyhedra which are dual polyhedra of the square antiprism and 4,4-bicapped square antiprism (gyroelongated square bipyramid), respectively. In CuSi 10 + and MSi16 (M=Cr, Mo, W) the central transition metals have the favored 18-electron rare gas configurations receiving electrons from the silicon atoms through Si2M three-center bonds analogous to the three-center C2M bonds in metal-olefin complexes. Thus in CuSi10 the silicon polyhedron functions as a chelating persila-tetraolefin whereas in MSi16 (M=Cr, Mo, W) the silicon polyhedron functions as a persila-octaolefin in which six of the eight double bonds are complexed to the central metal atom leaving two uncomplexed double bonds.  相似文献   

16.
Reaction of RCCH (R  Ph, CO2Meor CO2Et) with trans-[M(N2)2(dppe)2] (M  Mo or W; dppe  Ph2PCH2CH2PPh2) or [Mo(dppm)3] (dppm  Ph2PCH2PPh2) gives the alkyne complexes [M(RCCH)2(diphos)2] (diphos  dppe, M  Mo, R = Ph; dihpos  dppm, M  Mo, R  Ph or CO2Me) and the alkynyl complexes trans-[M(cCR)2(dppe)2], [MH2(CCR)2 (dppe)2] (M  Mo or W. R  Ph, CO2Me or CO2Et) and cis-[WH(CCCO2Me)(dppe)2]: the X-ray structure of trans-[Mo(CCPh)2(dppe)2] is reported.  相似文献   

17.
18.
Reaction of cyanamide (NCNH2) with trans-[M(N2)2(dppe)2] (M = Mo or W, dppe = PH2PCH2CH2PPh2) leads to the formation of the bis(cyanoimido) complexes trans-[M(NCN)2(dppe)2]. The crystal structure of trans-[Mo(NCN)2(dppe)2] has been determined by an X-ray diffraction study.  相似文献   

19.
《Polyhedron》2005,24(3):435-441
The title compounds were synthesized by the reactions of [NH4]2[MS4] (M = Mo, W), AgI and Hmimt in acetone and characterized by IR, 1H NMR and UV–Vis spectroscopy. The polymeric structure of [WS4Ag2(Hmimt)2]n was determined by X-ray crystallography. In this compound, there are two distinctly different coordination modes for the silver atoms. One Ag atom has a pseudo-tetrahedral geometry with one terminal monodentate-S Hmimt, two μ2-S bridging Hmimt and one S atom of a monodentate WS4 unit. The other is surrounded by four sulfur atoms belonging in pairs to two WS4 fragments; the coordination geometry is distorted tetrahedral. The [WS4Ag2(Hmimt)2]n polymer represents the first example of tetrathiometalate anions [MS4]2− (M = Mo, W, or V) coordinated to another metal atom in a monodentate fashion. In both crystal structures determined the Hmimt ligands are present in the thione form, with coordination taking place via the sulfur atom only.  相似文献   

20.
The reduction of [WCl4(PMe3)3] with dispersed sodium, under dinitrogen, gives cis-[W(N2)2(PMe3)4], while under ethylene trans-[W(C2H4)2(PMe3)4] is obtained. The ethylene complex can also be prepared by displacement of the dinitrogen molecules in cis-[W(N2)2(PMe3)4] by ethylene at room temperature and pressure. Interaction of cis-[M(N2)2(PMe3)4] complexes (M = Mo, W), with PMe3, under helium or argon, yields [M(N2)(PMe3)5]. The molybdenum complex crystallizes in the orthorhombic space group Pnma, with a 22.063(6), b 12.106(4), c 9.745(4) Å. The Mo—P distance trans to the dinitrogen ligand (2.483(7) Å) is slightly longer than the average of the other four Mo—P bonds (2.460(5) Å).  相似文献   

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