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1.
11NTRODUCTIONThetetrathiometalateanionsofseveraloftheear1yd-transitionmetalshavebeenshowntoactasligandstoawidevarietyofmetalionst1i.ThechemistryofFMoS'j'-and[WS'j'isbyfarthemosthighlydevelopedbecauseoftheirutilityasprecursorstolinearandcubane-typeMFe3S'clusters,someofwhich(M=Mo)arerelevanttothenativeMo-Fe-Sclusterofthenitrogenase"'.However,thedeepinvestigationonthecharacterizationof[VS'j'hasbeenhamperedfortheonlyknownisolatecompound(NH'),VS'isextremelyhydrolyticallysensitiveinwater…  相似文献   

2.
11NTRODUCTIONThetetrathiometalateanions[MS'j"-(M=Mo,W,V,Reetc.)havebeenshowntoactasligandstoawidevarietyofmetalions[li.Thechemistryof[MoS'j'-and[WS'j'-isbyfarthemosthighlydevelopedbecausesomeofthecubane-typeMoFe3S4clustersarerelevanttothenitrogenase"'andMo-Cuantagonismexistsinruminantst3i.However,[VS'j'hasnotbeendeeplyinvestigatedbecauseitissensi-tivetoairandmoisture.Evenso,theextensivevanadiumbiologicalfunctionhasim-pelledmoreandmorescientiststoprobeintothechemistryofthevanadiumco…  相似文献   

3.
StudiesontheV-Cu-SHeterometallicClusterCompounds(2).CrystalStructureof[VS_4(CuPPh_3)_5Br_2]·0.5CH_2Cl_2ZhengFa-Kun;YuXiu-Fen(Sta...  相似文献   

4.
标题两个化合物是在反应体系(NH4)3VS4/CuX/PPh3/NEt4X(X=Br,Ⅰ)中采用低温固相反应方法得到的,单晶X射线结构分析表明:VS4(CuPPh3)5Br2(Ⅰ)和VS4-(CuPPh3)5I2(Ⅱ)是同构的,其中晶体(Ⅰ)属于单斜晶系,空间群P211/c,Mr=19682,a=20.215(7),b=15.691(4),c=27.345(9)A,β=95.29(3)°,V=8637.0A3,Z=4,Dc=1.51g/cm3,F(000)=3968,μ(MoKa)=24.6cm-1,R=0.078。晶体(Ⅱ)亦属于单斜晶系,Mr=2062.2,空间群P21/c,a=20.1613(2),b=15.9718(2),c=27.7427(3)A,β=96.07(1)°,V=8883.4A3,Z=4,Dc=1.54g/cm3,F(000)=4112,μ(MoKa)=22.0cm-1,R=0.068。簇合物(Ⅰ)和(Ⅱ)的簇芯结构可描述为共面的2个开口的扭曲立方烷,在这两个簇合物中,V原子仍保持反应起始物[VS4]3-中的四面体配位,5个CU原子呈近似的四方锥排列,V原子基本上处于Cu5四方锥底面的中心。其中1个Cu原子为平面三角形配位,另外4个Cu原子为严重畸变的四面体配位。  相似文献   

5.
6.
Structural Studies of [V_2S_6O_2(CuPPh_3)_4(CuMeCN)_2]·2CH_2Cl_2·2PrOH   总被引:1,自引:0,他引:1  
StructuralStudiesof[V_2S_6O_2(CuPPh_3)_4(CuMeCN)_2]·2CH_2Cl_2·2PrOHZHANGHan-Hui;YUXiu-Fen;YANGRong-Sheng;ZHENGFa-Kun;HUANGLiao-Yu...  相似文献   

7.
合成了四个三核簇合物[A]2[MS4(CuCN)2](1A=Et4N,M=Mo;2A=PPh4,M=W;3A=Et4N,M=W;4A=PPh4,M=Mo),测定了[Et4N]2[MoS4(CuCN)2]*H2O(1*H2O)和[PPh4]2[WS4(CuCN)2]*0.5DMF*H2O(2*0.5DMF*H2O)的晶体结构.1和2的簇阴离子[MS4(CuCN)2]2-(M=Mo,W)均具有一个双齿配体MS42-和两个CuCN形成的近似D2d对称性结构.  相似文献   

8.
9.
刘泉  徐庆锋  张勇  陈金香  周志峰  郎建平 《中国化学》2002,20(12):1602-1607
IntroductionThechemistryofthethiometallateanionsiscurrentlyasubjectofintenseinterestduetotheirrichstructuraldi versity ,1 8theirrelevancetoindustrialcatalyticprocess9,10andmetalloenzymes ,11,12 andtheirpotentialutilityasnon linearopticalmaterials .13 16Wehaverep…  相似文献   

10.
新型六核双网兜状簇合物[MoS4Cu5Br3(Py)7]的合成与晶体结构   总被引:1,自引:0,他引:1  
以(NH4)2[Mo2S12]?H2O与过量CuBr在吡啶溶液中反应,得到了一个新型六核Mo/Cu/S簇合物[MoS4Cu5Br3(Py)7]。X-射线单晶结构分析表明它属于三斜晶系,空间群为P?C35H35Br3Cu5MoN7S4,Mr=1335.37,a=11.6274(4),b=12.0127(4),c=18.8872(5),a=82.46(2),b=73.25(2),g=62.800(13),V=2246.8(2)?,Z=2,F(000)=1300.0,Dc=1.974g/cm3,?=5.482mm-1,5718个独立可观察点(I>3(I)),最终偏离因子R和Rw分别为0.042和0.048。标题化合物是由2个相似的网兜状MoS3Cu3簇核通过共用MoSCuS平面形成的双网兜状结构,Mo…Cu距离在2.6830(11)~2.741(2)胖洹?  相似文献   

11.
The structural, electronic, bonding, magnetic, and optical properties of bimetallic [Cu(n)Ru(m)](+/0/-) (n + m ≤ 3; n, m = 0-3) clusters were computed in the framework of the density functional theory (DFT) and time-dependent DFT (TD-DFT) using the full-range PBE0 nonlocal hybrid GGA functional combined with the Def2-QZVPP basis sets. Several low-lying states have been investigated and the stability of the ground state spinomers was estimated with respect to all possible fragmentation schemes. Molecular orbital and population analysis schemes along with computed electronic parameters illustrated the details of the bonding mechanisms in the [Cu(n Ru(m)](+/0/-) clusters. The TD-DFT computed UV-visible absorption spectra of the bimetallic clusters have been fully analyzed and assignments of all principal electronic transitions were made and interpreted in terms of contribution from specific molecular orbital excitations.  相似文献   

12.
The solid state structures of seven tetrapropoxycalix[4]arene derivatives immobilised in a 1,3-alternate conformation were determined using single-crystal X-ray crystallography. The cavity shapes of investigated derivatives (upper rim unsubstituted, distally di-substituted and tetra-substituted) and the nature of intermolecular interactions in molecular packing were compared. The results indicate that there are only two structural types adopted by basic tetrapropoxycalix[4]arene derivatives in the 1,3-alternate conformation.  相似文献   

13.
在过去20多年里,人们对合成Mo(W)/Cu/S簇合物一直抱有浓厚的兴趣,这主要缘于此类簇合物丰富的结构化学,以及在生命科学和材料科学方面的潜在应用前景[1,2].在这些簇合物中,含吡啶类配体的Mo(W)/Cu/S簇合物的合成因具有良好的三阶非线性光学性质,近年来受到人们的青睐[3~8].  相似文献   

14.
The synthesis of a Cu4(OH)4 cube which is coordinated by four molecules of the dipyridyl ligand 1,6-[di(pyridin-4-yl)hex-3-ene] is reported. This compound has a trans double bond which restricts the conformational freedom of the ligand and favours coordination within a unique copper cube. The structure was solved by an X-Ray single crystal structure determination and low temperature magnetic susceptibility measurements examined its magnetic properties. The cube classification corresponds to the type I classification of Mergehenn and Haase and the short/long distribution of Cu ⋅⋅⋅ Cu separations in the cube as defined by Ruiz. The magnetic susceptibility measurements show paramagnetic behaviour down to 50 K but below this the copper cube shows weak ferromagnetic exchange interactions. The low temperature magnetic susceptibility characteristics are examined in detail then modelled and compared to other similar Cu4O4 copper cubes.  相似文献   

15.
Reaction of bis(pyrazol‐1‐yl)acetic acid with n‐Bu2SnO in a 1:1 molar ratio gives dimeric bis[dicarboxylatotetraorganodistannoxanes], {[(n‐Bu)2(Pz2CHCO2)Sn]2O}2 (Pz = pyrazol‐1‐yl or 3,5‐dimethylpyrazol‐1‐yl), which are characterized by IR and NMR (1H, 13C and 119Sn) spectra and elemental analyses. The X‐ray crystal structure analyses indicate that {[(n‐Bu)2(Pz2CHCO2)Sn]2O}2 is a centrosymmetric dimer with a cyclic Sn2O2 unit, in which each tin atom is situated in a distorted trigonal bipyramidal geometry. In addition, bis(3,5‐dimethylpyrazol‐1‐yl)acetic acid in the solid state forms a dimer through two intermolecular O? H···N hydrogen bonds. These organotin derivatives display low fungicide, insecticide and miticide activities, but display certain cytotoxicities for Hela cells in vitro. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

16.
According to the protonation of [PPh4]2[Ru6C(CO)16] (1b) withp-toluene-sulfonic acid, a hydrido ruthenium cluster [PPh4][Ru6C(CO)16H] (3b) was obtained in 53% yield, which readily decomposed in protic solvents even at –20°C to yield1b, Ru6C(CO)16H2, and Ru5C(CO)15. Cluster3b was characterized by single-crystal X-ray analysis. The six metal atoms are arranged in the form of an octahedron with the carbido ligand located in the center. There are 13 terminal carbonyl, three bridging carbonyl, and a bridging hydrido ligands.  相似文献   

17.
Studies using density functional theory (DFT) at the hybrid B3LYP level indicate that the relative energies of structures with three-fold, four-fold, and five-fold symmetry for centered 10-vertex bare germanium clusters of the general type M@Ge(10) (z) depend on the central metal atom M and the skeletal electron count. For M@Ge(10) clusters with 20 skeletal electrons the DFT results agree with experimental data on the isoelectronic centered 10-vertex bare metal clusters. Thus the lowest energy structure for Ni@Ge(10), isoelectronic with the known Ni@In(10) (10-), is a C(3v) polyhedron derived from the tetracapped trigonal prism. However, Zn@Ge(10) (2+) is isoelectronic with the known cluster Zn@In(10) (8-), which has the lowest energy structure, a D(4d) bicapped square antiprism. For the clusters Ni@Ge(10) (2-), Cu@Ge(10) (-), and Zn@Ge(10) that have 22 skeletal electrons the lowest energy structures are the D(4d) bicapped square antiprism predicted by the Wade-Mingos rules. For the clusters Ni@Ge(10) (4-), Cu@Ge(10) (3-), and Zn@Ge(10) (2-) that have 24 skeletal electrons the lowest energy structures are C(3v) polyhedra with 10 triangular faces and 3 quadrilateral faces derived from a tetracapped trigonal prism by extreme lengthening of the edges of the capped triangular face of the underlying trigonal prism. For the clusters Cu@Ge(10) (5-) and Zn@Ge(10) (4-) that have 26 skeletal electrons the lowest energy structures are the D(5d) pentagonal antiprisms predicted by the Wade-Mingos rules and the C(3v) tetracapped trigonal prism as a somewhat higher energy structure. However, for the isoelectronic Ni@Ge(10) (6-) the relative energies of these two structure types are reversed so that the C(3v) tetracapped trigonal prism becomes the global minimum. The effects of electron count on the geometries of the D(5d) pentagonal prism and D(4d) bicapped square antiprism centered metal cluster structures are consistent with the bonding/antibonding characteristics of the corresponding HOMO and LUMO frontier molecular orbitals.  相似文献   

18.
王开亮  汪清民  黄润秋 《有机化学》2008,28(10):1826-1829
以吡咯为起始原料, 以三氟氧钒(VOF3)氧化偶联重排反应为关键步骤, 经过7步反应, 合成了结构骨架全新的14-羟基菲并[9,10,3’,4’]吲哚里西啶化合物8, 总收率为55%. 采用1H NMR, 13C NMR, IR, MS和HRMS对中间体和目标产物进行了表征. 初步的抗烟草花叶病毒生物活性测试结果表明, 目标化合物8对烟草花叶病毒无明显抑制作用, 但具有较好的抗肿瘤活性, 中间体9-氧代-14-羟基-14a-甲氧基菲并[9,10,3’,4’]吲哚里西啶化合物7却表现出了很好的抗烟草花叶病毒活性.  相似文献   

19.
A suite of branched-chain pyrogallol[4]arene (Pg) macrocycles, most of which show activity in bilayer membranes, has been prepared and studied by X-ray crystallography. The little-known branched side-chain Pgs include 2-propyl, 2-butyl, 2-pentyl, 3-pentyl, 3-heptyl, 4-heptyl, 5-nonyl and cyclohexyl. The Pgs form self-assembled structures having bilayer, capsule or, in one case, a nanotube morphology. The nanotube structure observed for C-(di-n-ethyl)pyrogallol[4]arene was confirmed by X-ray structure analysis and by transmission and scanning electron microscopies.  相似文献   

20.
The tetranuclear nickel cluster {[Ni4(L)4(C2H5OH)4] · 7H2O} ( 1 ) was synthesized based on the tridentate Schiff base ligand H2L = 1‐phenyl‐3‐[(2‐hydroxyphenyl)imino]‐1‐butanone. The structure of 1 was determined by single‐crystal X‐ray diffraction. It exhibits a discrete [Ni4O4] cluster. Magnetic studies indicate that ferromagnetic interactions exist within compound 1 . Furthermore, thermogravimetric analysis and PXRD patterns in various solvents reveal thermal and solvent stability of compound 1 .  相似文献   

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