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1.
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   

2.
Oxo/hydoxo zirconium(IV) complex of the general formula [Zr63-O)43-OH)4(OOCCH2tBu)92-OH)3]2 has been isolated, when Zr(OiPr)4 reacted with a 2-fold excess of 3,3-dimethylbutyric acid. Single crystal X-ray diffraction data, collected at 103 and 153 K, showed that the studied compound crystallizes in hexagonal system (P63/m (no. 176)). Structure consists of dimers composed of [Zr63-O)43-OH)4(OOCCH2tBu)9] sub-units, linked by six μ2-OH bridges. Infrared spectroscopic studies proved the presence of hydroxo groups in the structure of studied clusters and formation of different types of oxo/hydroxo bridges. The application of variable temperature infrared spectroscopy and differential scanning calorimetry revealed that the structure of this complex undergoes the phase transitions at 143–183 and 203–293 K. Comparison of spectral and crystallographic data suggests that these phase transitions might be related to changes in the strength of Zr–O bonds of μ2-OH bridges linking complex sub-units, and change in symmetry of the crystal lattice (from hexagonal to trigonal). Analysis of thermogravimetric data showed that decomposition of [Zr63-O)43-OH)4(OOCCH2tBu)92-OH)3]2 proceeds with complete conversion to ZrO2 (monoclinic form) between 603 and 803 K.  相似文献   

3.
A new polymer azido-bridged copper(II) complex [Cu4(En)21,1-N3)41,1,1-N3)21,3-N3)2] n (I) (En = ethylenediamine) has been synthesized and crystallography characterized. Complex I shows one-dimensional coordination polymeric structure based on a tetranuclear cluster unit [Cu4(En)21,1-N3)41,1,1-N3)21,3-N3)2], in which the azido ions display three different bridging modes.  相似文献   

4.
The reaction between AuMe(PPh3) and Ru3(μ-H)33-CBr)(CO)9 (1) affords the novel heptanuclear cluster Au4Ru33-CMe)(Br)(CO)9(PPh3)3 (2), containing an Au/Ru3/Au trigonal pyramidal cluster face-capped by two Au(PPh3) groups and a CMe ligand, together with Au2Ru3(μ-H)(μ3-CMe)(CO)9(PPh3)2 (3), formed by isolobal replacement of two of the three μ-H atoms in 1 by Au(PPh3) groups. The latter co-crystallises with the analogous μ3-CH complex, as also shown spectroscopically.  相似文献   

5.
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   

6.
本文首次报道三元体系Cu(NO3)2-CO(NH2)2-H2O(30℃)和La(NO3)3-CO(NH2)2-H2O(25℃)的等温溶度及饱和溶液、折光率,绘制相应的溶度图及折光率-组成图。体系中发现有组成为Cu(NO3)2·4CO(NH相似文献   

7.
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   

8.
Reactions of [(dtc)2Mo2(S)2(μ-S)2] with one or two equivalents of CuBr in CH2Cl2 afforded two new heterobimetallic sulfide clusters, [(dtc)2Mo23-S)(μ-S)3(CuBr)] (1) and [(dtc)2Mo23-S)4(CuBr)2] (2). Both compounds were characterized by elemental analysis, IR, UV-vis and X-ray analysis. Compound 1 contains a butterfly-shaped Mo2S4Cu core in which one CuBr unit is coordinated by one bridging S and two terminal S atoms of the [(dtc)2Mo2(S)2(μ-S)2] moiety. In the structure of 2, one [(dtc)2Mo2(S)2(μ-S)2] moiety and two CuBr units are held together by six Cu-μ3-S bonds, forming a cubane-like Mo2S4Cu2 core.  相似文献   

9.
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   

10.
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   

11.
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   

12.
Mechanochemical reaction of cluster coordination polymers (Q=S, Se) with solid leads to the cluster core excision with the formation of anionic complexes . Extraction of the reaction mixture with water followed by crystallization gives crystalline (main product) and (1) (minor product). In the case of the Se cluster, the complex could not be isolated, and the treatment of the aqueous extract with PPh3 gave (2) in a low yield. Alternatively, it was obtained from and in high yield. Both 1 and 2 were characterized by X-ray structure analysis. Dedicated to Academician I. I. Moiseev on the occasion of his 75th birthday and in recognition of his outstanding contribution to cluster chemistry.  相似文献   

13.
《物理化学学报》1999,15(6):6-31G
用密度泛函理论UB3LYP/6-31G(d,p)方法研究了二甲胺自由基(CH  相似文献   

14.
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   

15.

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   

16.
New mixed-ligand coordination compounds[Cd(DMSO)5(NCS)][Cr(NH3)2(NCS)4] · 3DMSO (I) and [Mn(DMSO)4(H2O)2][Cr(NH3)2(NCS)4]2 · 6DMSO · 2H2O (II) have been synthesized and studied by IR spectroscopy and X-ray diffraction analysis. The crystals of compound I are monoclinic, a = 14.5275(7), b = 23.1692(11), c = 14.6969(6) ?, β = 97.057(2)°, V = 4909.4(4) ?3, space group P21/c, Z = 4, ρcalcd = 1.507 g/cm3, R = 0.0556. The crystals of compound II are triclinic, a = 11.7784(3), b = 12.1760(3), c = 13.1922(2) ?, α = 85.5420(10)°, β = 87.9000(10)°, γ = 70.3680(10)°, V = 1776.46(7) ?3, space group P , Z = 1, ρcalcd = 1.444 g/cm3, R = 0.0350. Original Russian Text ? E.A. Gerasimova, T.V. Utkina, E.V. Peresypkina, A.V. Virovets, T.G. Cherkasova, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 5, pp. 751–755.  相似文献   

17.
合成了希土高氯酸盐开环冠醚二缩乙二醇(EO2)晶体,(Ln=Nd, Ho),测定了结构,文内以Nd-L的数据为主要研究对象(方括号内是Ho-L的数据)。晶体属单斜晶系,P21/n空间群,化学式[Ln(EO2)3](ClO4)3·3H2O,晶胞参数为:a=14.124(1)[14.087], b=13.990(1)[14.039], c=15.265(1)[15.014]?; β=95.78(1)[95.64]°; V=3001.1(6)[2955]?3; Mr=815.01[835.70]; Z=4; Dc=1.804[1.865]g/cm3;石墨单色器,μ(MoKα)=2.09[3.07] mm-1,最终偏离因子R=0.055[0.074], RW=0.071[0.109]。研究结果表明晶体具有相同的结构,配位多面体为九配位三帽三棱柱。发现EO2醚链有绕C-C键呈STT分布的规律。弱配体高氯酸根不参加配位。  相似文献   

18.
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   

19.
The solubilities and nature of solid phases in the Co(NO3)2-(CH3)2SO-H2O system were studied at 25°C. A new congruently saturating compound was recovered: Co(NO3)2 · 4(CH3)2SO · 2H2O. The concentration boundaries of its crystallization in the system were determined. The compound was studied by the Schreinemakers wet residue method, X-ray powder diffraction, differential thermal analysis, crystal-optical analysis, and IR spectroscopy.  相似文献   

20.
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   

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