首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 734 毫秒
1.
New cluster complexes [W3S4(Acac)3(PPh3)3]PF6 · 0.5CHCl3 (Acac = CH3C(O)CHC(O)CH3) (I) and [W3S4(Hfac)3(PPh3)2Br] · 2CHCl3 (Hfac = CF3C(O)CHC(O)CF3) (II) were synthesized. Their molecular and crystal structures were determined by X-ray diffraction. The cis-cis type of coordination of acetylacetonate and hexafluoroacetylacetonate ligands in I and II, respectively, was established, and the PPh3 ligands were found in the trans-positions with respect to the “capping” sulfide ligand (μ3-S).  相似文献   

2.
Novel anhydrous trinuclear 3-oxo complexes of Cr(III), Cr3(3-O)(CF3COO)6(CH3COOH)2(CF3COO) (I) and of Cr(III,III,II), Cr3(3-O)(CF3COO)6(CH3COOH)2(THF) (II) (where THF is (CH2)4O) are synthesized by anodic dissolution of metallic chromium in solutions of trifluoroacetic acid in acetonitrile and in tetrahydrofuran and their structures are studied by X-ray diffraction analysis. Complex I forms orthorhombic crystals with space group Pna21, a = 9.778(1) , b = 16.042(2) , c = 22.851(4) , Z = 4, R 1 = 0.0332; complex II crystallizes in monoclinic system: space group P21/c, a = 9.866(1) , b = 17.895(2) , c = 21.167(4) , = 100.75(2)°, Z = 4, R = 0.0422. The average Cr-(3-O) distances in compounds I and II are almost equal (1.943(3) and 1.927(3) ). An average length of the Cr-O bond in octahedral surrounding of metal atoms is different in complexes I and II (1.985(4) and 2.003(3) , respectively), which is specified by different oxidation states of the metal atom. The CrCr distances lie in an interval of 3.366(1)–3.337(1) .__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 4, 2005, pp. 266–272.Original Russian Text Copyright © 2005 by Glazunova, Boltalin, Troyanov.  相似文献   

3.
New half-sandwich titanocene complexes (η5-C5Me5)Ti(OC6F5)3 (1), (η5-C5Me5)Ti(OCH2C6F5)3 (2), and (η5-C5Me5)Ti(OCH2C6F2H3)3 (3) were synthesized via the displacement of methoxide ligands in (η5-C5Me5)Ti(OMe)3 by the corresponding aryloxy or benzyloxy ligands. These compounds have been fully characterized by various spectroscopic methods including X-ray crystallography. Compound 1 has a distorted three-legged piano stool structure. However, complexes 2 and 3 have the chariot-like structure, where chariot means a two-wheeled horse-drawn vehicle. The π electron donation of oxygen atom to Ti center in complexes 1-3 is considerable.  相似文献   

4.
The reduction of trans-[Pd(NHC)2Cl2] (NHC = IMes, 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene; IiPr2 = 1,3-bis-isopropylimidazol-2-ylidene) with potassium graphite under an atmosphere of CO affords the palladium NHC carbonyl clusters [Pd3(μ-CO)3(NHC)3] (NHC = IMes, 1; IiPr2, 3). Treatment of 1 with SO2 at room temperature yields the bridging SO2 complex [Pd3(μ-SO2)3(IMes)3] (4) in quantitative yield. Complexes 1, 3 and 4 have been structurally characterised by X-ray crystallography.  相似文献   

5.
The reaction of [Cu3(dppm)33-OH)](ClO4)2 (1) with heterocumulenes (XCS; X = NPh, NMe and S) has been studied. The μ3-OH ligand inserts into PhNCS and MeNCS only in the presence of methanol. Insertion products are formed in accord with earlier observations made with copper(I)-aryloxides. On heating, the insertion products convert to a S bridged cluster [Cu4(dppm)44-S)](ClO4)2 (8), having a tetrameric core. However, in the reaction with CS2, 1 is converted to 8 even at room temperature in the presence of methanol. On the other hand, the dimeric complex [Cu2(dppm)2(CH3CN)4](ClO4)2, reacts with CS2 to give (diphenylphosphinomethyl)-diphenylphosphine sulfide, Ph2P-CH2-P(S)Ph2 (dppmS), which forms the complex [Cu(dppmS)2]ClO4 (9). A single crystal X-ray crystallographic study of 9, the first copper(I) complex of dppmS has been taken up to confirm the mono-oxidation of the dppm ligand and the nuclearity of the complex. Reactions of complex 1 with heterocumulenes and with elemental sulfur, are compared.  相似文献   

6.
7.
Methods for the synthesis of trans-diammino complexes [RuNO(NH3)2(NO2)2(OH)] (I) and [RuNO(NH3)2(H2O)(NO3)2](NO3)·H2O (II) are suggested. The compounds were studied by IR spectroscopy and X-ray phase and X-ray structural analyses. Crystal data: space group P-1; a = 6.2328(2) ?, b = 11.0488(3) ?, c = 11.0981(4) ?, α = 71.942(1)°, β = 83.291(1)°, γ = 86.877(1)° (I); space group P21; a = 6.6290(2) ?, b = 13.4389(5) ?, c = 7.0180(2) ?, β 114.281(1)° (II). Complex II readily lost some part of crystal water on storage in open air. Original Russian Text Copyright ? 2009 by M. A. Il’in, E. V. Kabin, V. A. Emel’yanov, I. A. Baidina, and V. A. Vorob’yov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 2, pp. 341–348, March–April, 2009.  相似文献   

8.
Thermal behaviour of hexaamminenickel(II) nitrate and tris(ethylenediamine)nickel(II) nitrate have been investigated by means of simultaneous thermogravimetry/DTA coupled online with mass spectral (MS) studies and temperature resolved X-ray diffraction (TR-XRD) techniques under inert atmospheric condition. Both the complexes produce highly exothermic reactions during heating due to the oxidation of the evolved ammonia or ethylenediamine by the decomposition products of Ni(NO3)2. Evolved gas analysis by MS studies detected fragments like NH2 and NH ions with weak intensity. The decomposition of nitrate group generates N, N2, NO, O2 and N2O species. Ethylenediamine (m/z 60) is fragmented to H2 (m/z 2), N (m/z 14), NH3 (m/z 17) and CH2=CH2/N2 (m/z 28) species. The formation of the intermediates was monitored by in situ TR-XRD. The residue of thermal decomposition for both the complexes was found to be crystalline NiO in the nano range.  相似文献   

9.
The quantum yield for arene displacement from (η6-C6H5Y)Cr(CO)3 was measured in 1,1,2-trifluorotrichloroethane (Y = NH2, OCH3, H, CHO, or CO2CH3). Values of 0.24, 0.27, 0.15, 0.17, and 0.32 were obtained respectively (λexc. = 355 nm). These values are significantly higher than those measured for photoinduced arene loss in hydrocarbon solvents using the same excitation wavelength. Laser flash photolysis of (η6-C6H5Y)Cr(CO)3 in 1,1,2-trifluorotrichloroethane (λexc. = 355 nm) resulted in the rapid formation (<10 ns) of Cr(CO)6. Matrix isolation experiments on (η6-C6H5Y)Cr(CO)3 (Y = H or CHO) at 12 K in CH4 or CO-doped CH4 matrixes using monochromatic irradiation confirmed the presence of two discrete excited states, one leading to CO-loss and the other to arene-loss. The results correlate with the calculated electron drift in the excited state derived from density functional theory and time dependent density functional theory calculations.  相似文献   

10.
Reactions of Ru3(CO)12 with PhTeBr3 and of Re(CO)5Cl with PhTeI in benzene give the stable complexes (CO)2RuBr2(PhTeBr)2 (I) and (CO)3Re(PhTeI)33-I) (II) containing two and three ligands PhTeX (X = Br or I), respectively. The bonds between these ligands and the central metal atom are fairly shortened (on average, Ru-Te, 2.608 ?; Re-Te, 2.7554(12)-2.7634(13) ?). The Te-X bonds in the ligands PhTeBr (2.5163(5) ?) and PhTeI (2.7893(15) ?) are not lengthened appreciably. In complex II, the iodide anion is not coordinated by rhenium, yet being attached through weak secondary bonds to three Te atoms of the three ligands PhTeI.  相似文献   

11.
A reaction of the dimer [Mn(CO)4(SPh)]2 with (PPh3)2Pt(C2Ph2) gave the heterometallic complex (CO)4Mn(μ-SPh)Pt(PPh3)2 (I) and its isomer (CO)3(PPh3)Mn(μ-SPh)Pt(PPh3)(CO) (II). A reaction of complex I with a diphosphine ligand (Dppm) yielded the heterometallic complex (CO)3Mn(μ-SPh)Pt(PPh3)(Dppm) (III). Complexes IIII were characterized by X-ray diffraction. In complex I, the single Mn-Pt bond (2.6946(3) ?) is supplemented with a thiolate bridge with the shortened Pt-S and Mn-S bonds (2.3129(5) and 2.2900(6) ?, respectively). Unlike complex I, in complex II, one phosphine group at the Pt atom is exchanged for one CO group at the Mn atom. The Mn-Pt bond (2.633(1) ?) and the thiolate bridge (Pt-S, 2.332(2) ?; Mn-S, 2.291(2) ?) are retained. In complex III, the Mn-Pt bond (2.623(1) ?) is supplemented with thiolate (Pt-S, 2.341(2) ?; Mn-S, 2.292(2) 0?) and Dppm bridges (Pt-P, 2.240(1)?; Mn-P, 2.245(2) ?). Apparently, the Pt atom in complexes IIII is attached to the formally double bond , as in Pt complexes with olefins.  相似文献   

12.

Abstract  

Thermolysis of cis-Fe(CO)4(SiCl3)2 results in the formation of the novel compound Fe2(CO)62-SiCl2)3, which was characterized by single crystal X-ray diffraction. Density functional theory calculations were carried out to elucidate possible reaction steps leading to the formation of Fe2(CO)6(SiCl2)3, including CO dissociation and chlorine abstraction by a SiCl3 radical generated from homolytic Fe–Si bond cleavage involving a singlet–triplet intersystem crossing.  相似文献   

13.
Trinuclear M3tdt3(PEt3)3 (M = FeII for I, CoII for II) clusters have been synthesized from the reaction between M(PEt3)2Cl2 and Na2tdt (tdt = toluene-3,4-dithiolate) in MeCN. Both complexes have been characterized by elemental analyses, FT-IR, UV–Vis, FAB-MS, 1H NMR and cyclic voltammetry. Structures of Fe3tdt3(PEt3)3 (I) and Co3tdt3(PEt3)3 (II) were determined by single crystal X-ray crystallography. The Fe3 triangular core of the 48-electron complex I, with an isosceles triangular geometry, showed very short Fe–Fe distances of 2.4014(13) and 2.4750(12) Å, which are comparable to the extensive M–M frameworks found in the FeMo-cofactor in nitrogenase. The isostructural Co3tdt3(PEt3)3 (II), with an analogous Co3 coordination geometry, showed short Co–Co distances of 2.4442(9) and 2.5551(10) Å. The slightly longer M–M distances in complex II were explained by a total valence electron counting argument. Cyclic voltammetry of Fe3tdt3(PEt3)3 (I) showed robust reduction waves compared to Co3tdt3(PEt3)3 (II). Temperature-dependent effective magnetic moment measurements of I and II showed both clusters behave similarly and the magnetic property of the M3 equilateral triangle core with extensive metal–metal interactions was characterized as degenerate frustration.  相似文献   

14.
The crystal structure of [(C5Me4Et)3Rh33-Se)2](PF6)2 and [(C5Me4Et)2Rh22-Cl)3]PF6, obtained in the reaction of [(C5Me4Et)Rh(C6H6)](PF6)2 with ZnSe in 4M HCl under hydrothermal conditions, is determined. In agreement with the 18VE rule, the triangular cluster contains single metal-metal bonds (Rh-Rh 2.864(1) ?), whereas they are absent in the binuclear complex (Rh ...Rh 3,216(1) ?). Original Russian Text Copyright ? 2009 by P. A. Abramov, M. N. Sokolov, A. V. Virovets, and V. P. Fedin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 1, pp. 169–172, January–February, 2009.  相似文献   

15.
The products of the extraction treatment of Rh(III) and Pd(II) nitrate-nitrite solutions are studied. The [Rh(Thio)6](NO3)3·3H2O and [Pd(Thio)4](NO3)2 complex salts are extracted and an X-ray diffraction analysis of single crystals is performed (BRUKER X8 APEX automated diffractometer, MoK a radiation, graphite monochromator, two-dimensional CCD-detector). [Rh(Thio)6](NO3)3·3H2O crystallographic characteristics are as follows: a = 15.1857(3) ?, b = 10.7292(2) ?, c = 18.8524(4) ?, β = 105.165(1)°, P2 1 /c space group, Z =4; [Pd(Thio)4](NO3)2: a = 5.8013(4) ?, b = 7.0981(5) ?, c = 11.4991(8) ?, α = 99.963(2)°, β = 101.410(2)°, γ = 102.229(2)°, P —1 space group, Z = 1.  相似文献   

16.
New cluster complexes [Mo3S4(Dppen)3Cl3]PF6 · 1.5CH2Cl2 (Dppen = cis-Ph2PCH=CHPPh2) (I) and [W3S4(Dppe)3Br3]2(ZnBr4)2 · 5.5CH3CN (Dppe = Ph2PCH2CH2PPh2) (II) were synthesized. Their molecular and crystal structures were determined by X-ray diffraction. Diphoshine ligands in the complexes I and II are coordinated in the bidentate mode, providing an arrangement of three chelate rings, giving rise to chirality.  相似文献   

17.
李秀珍  吕永康 《无机化学学报》2009,25(10):1868-1872
利用物质在恒温相变过程中吸收或释放能量的特性,将暂时不用的能量储存起来,待需要时再加以利用,这类材料统称为相变储能材料,被广泛应用于空调节能、建筑节能、甚至空间技术等方面[1-5].  相似文献   

18.
Syntheses and crystal structures of [tBu3SbCr(CO)5] (1), [tBu3BiM(CO)5] [M = Cr (2), W (3)] and [tBu3BiMnCp′(CO)2] (4) (Cp′ = η5-C5H4CH3) are reported.  相似文献   

19.
Phases of a variable composition in the Ba3−x Sr x Y(BO3)3, system (0 < x < 3) have been investigated for the first time using the solid-phase reactions method. The formation of two series of solid solutions crystallizing in different structural types have been established using X-ray diffraction (D-8 Advance diffractometer, CuK α radiation, graphite monochromator). Crystal characteristics of obtained phases have been determined. Original Russian Text ? T.N. Khamaganova, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 4, pp. 553–556.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号