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1.
1 INTRODUCTION The complexes of syn- or anti-[(5-C5Me5)2- W2(S)2(-S)2] could be prepared in several ways[1~5]. For example, a mixture consisting of [Et3NH][(5-C5Me5)WS3] and anti-[(5-C5Me5)2- W2(S)2(-S)2] was generated from the reactions of [(5-C5Me5)WCl4] with H2S in the presence of NEt3[2]. The reactions of [(5-C5Me5)W(NO)I2] with H2S led a mixture of [(5-C5Me5)W(S)(S2)I] and anti-[(5-C5Me5)2W2(S)2(-S)2][3]. [(5-C5Me5)W- (StBu)3] was degraded in THF at room temperat…  相似文献   

2.
环戊二烯基希土氯化物是一类合成希土有机配合物的重要前身。尽管在1980年前没能成功地合成含轻希土元素的这类配合物,但目前已发现,采用具有较大体积的取代环戊二烯做配体,如C_5Me_5H,C_5H_3〔Si(CH_3)_3〕_2H,C_5Me_4C_3H_7H和桥联的配体(C_5H_4)_2(CH_2)_3H_2都可得到相应的取代环戊二烯基轻希土氯化物。控制LnCl_3和CpNa的反应摩尔比也可以成功地得到这类轻希土的环戊二烯基氯化物。  相似文献   

3.
合成了(η~5-C_5H_5)_2Nb[CH_2Si(CH_3)_3]_2化合物,并测定了它的晶体结构及溶液和玻璃态固体的EPR;通过计算机模拟玻璃态固体EPR得到了g和T的分量;测得最高占据分子轨道的a~2/b~2=10.3。  相似文献   

4.
本文报道了两个具有松散配位的三核钼簇合物{Mo_3(μ_3—S)(μ—S)_3[S_2P(OEt)_2]_4·(C_3H_3ON)}·CH_3GN(Ⅰ)、{Mo_3(μ_3—O)(μ—S)_3[S_2P(OEt)_2]_4(C_3H_3ON)}(Ⅱ)的合成和晶体结构。簇合物(Ⅰ)属单斜晶系,空间群为P2_2/n,晶胞参数为a=16.579(3),b=16.959(2),c=16.867(2);β=94.44(1)°;v=4728 3;Z=4;D_c=1.778g·cm~(-3),用Patterson法解出结构,最终偏离因子R=0.045。簇合物(Ⅱ)属三斜晶系,空间群为P1,晶胞参数为a=13.175(4),b=13.372(6),c=16.656(3);α=117.87(4)°,β=60.09(3)°,γ=109.03(3)°;ν=2231 3;Z=2;D_c=1.798g·cm~(-3),用直接法解出结构,最终偏离因子R=0.066。两个簇合物均为以具有一个松散配位为特征的单帽三核簇,而且松散配位上均被一嘿唑五员环所占据,其主要差别在于簇合物(Ⅰ)的簇胳为Mo_3S_4,而簇合物(Ⅱ)则为一Mo_3OS_3·文中对这一“松散”配位的三核钼簇合物的活泼性进行了讨论。  相似文献   

5.
标题晶体属斜方晶系,空间群Pbn2_1,a=9.086(2),b=13.439(3),c=22.858(11),V=2791,Z=4,Dc=1.927g/cm~3。在CAD—4衍射仪上收集强度数据,采用直接法和Fourier技术解出结构,并用全矩降最小二乘法修正。对于1180个独立衍射最终偏离因子0.067。结构中的阴离子与其同系物[(CH_3)_4-N]_2K(Mo_2O(S_2)_3(NO)_2]·H_2O中的阴离子配位情况相似。只是结构中的Mo—S与Mo—O键长有差异。这种差异在两者的红外光谱上有着相应的表现。  相似文献   

6.
本文通过η~5-Bz_5C_5MNa与氧化偶联试剂Fe_2(SO_4)_3/HOAc/H_2O的反应合成了含η~5-五苄基环戊二烯基配体的两个金属-金属单键化合物[η~5-Bz_5C_5(CO)_3M]_2(1:M=Mo;2:M=W),产率分别为45%和19%。1在沸腾的甲苯中可进一步脱羰而以98%的产率生成金属-金属三键化合物[η~5-Bz_5C_5(CO)_2Mo]_2(3)。1~3的结构均经碳氢分析,IR,~1H NMR和MS鉴定。3的结构尚被单晶X射线衍射分析确证。该晶体属单斜晶系,空间群P2_1/c,晶体学数据:。α=1.1335(5),b=1.3823(4),c=2.1655(6)nm;β=102.33(3)°;V=3.315(2)nm~3;Z=2;D_x=1.34g/cm~3;F(000)=1380。  相似文献   

7.
<正> The crystal structure of the complex [Li(THF)4]2[{(η5-CH3C5H4)Nd-Cl(μ2-Cl)NdCl2(η5-CH3C5H4)}2(μ4-O)] has been determined by X-ray diffraction technique. The crystal is monoclinic of space group C2/c with a = 22. 740(7) ,b= 18. 319 (6),c=18. 330(6) A,β=93. 04(3)°,V = 7624. 93A3,Dc= 1. 55g/cm3,Z = 4,F(000) = 2800,μ=15. 02cm-1. The complex is consisted of two [Li(THF)4]+cations and one [{(η5-CH3C5H4)NdCl(μ2-Cl)NdCl2(η5-CH3C5H4)}2(μ4-O)]2-dianion. The two units [Cη5-CH3C5H4)NdCl(μ2-Cl)NdCl2(η5-CH3C5H4)] in the tetra nnclear-neodymium dianion are connected by a μ4-O bridge with the average Nd -μ4-O 2. 36(1) A ,Nd -C(ring) 2. 76(3)A,Nd-Cl 2. 823(7)A and Nd-μ2-Cl 2. 798(7)A.  相似文献   

8.
The synthesis and crystal structure of two trinuclear molybdenum clusters containing a loosecoordination site, {Mo_3(μ_3-S)(μ-S)_3[S_2P(OEt)_2]_4(C_3H_3ON)}· CH_3CN (Ⅰ) and {Mo_3(μ_3- O)-(μ- S)_3[S_2P(OEt)_2]_4(C_3H_3ON)} (Ⅱ), are reported. Cluster (Ⅰ) belongs to the monoclinic spacegroup p2_1/n, a = 16.579 (3), b = 16.959 (2), c = 16.867 (2) A, β= 94.44 (1)°, V = 4728A~3,Z = 4, D_c = 1.778g·cm~(-3). The crystal structure was solved by the Patterson method with afina1 R value of 0.045. Cluster (Ⅱ) belongs to the triclinic space group Pi, a = 13.175 (4),b = 13.372(6), c = 16.656(3)A, α= 117.87(4), β= 60.09(3), γ= 109.03(3)°, ν= 2231A~3,Z = 2, D_3 = 1.798g·cm~(-3). Direct methods were used to solve the crystal structure with afinal R value of 0.066. Both clusters are monocapped trinuclear ones having an oxazoleoccupied coordination site as their main structural characteristic. The difference in cappingatoms results in the difference in their skeletons, Mo_S_4 in cluster (Ⅰ) vs. Mo_3OS_3  相似文献   

9.
1 INTRODUCTION In the last decade, we have been interested in the synthesis of [PPh4][(h5-C5Me5)MS3] (M = Mo, W)[1, 2] , Whose organometallic trisulfido anions show high reactivity towards various transition metals[3~6] . We once reported that the reaction of [PPh4][(h5-C5Me5)WS3] with CuBr in CH3CN afforded a double incomplete-cubane cluster [PPh4]2[(h5-C5Me5)WS3(CuBr)3]2[3], while the analogous reaction of [PPh4][(h5-C5Me5)WS3] with CuBr in CHCl3 gave rise to a 揻our-…  相似文献   

10.
The reaction of [(η5-C5Me5)2Mo2(μ3-S)4(CuCl)2] 1 with Na2S in MeCN produced a trinuclear cluster [(η5-C5Me5)2Mo2(μ3-S)(μ-S)3(CuCl)] 2. 2 crystallizes in the monoclinic system, space group P21/c with a = 15.563(3), b = 8.9547(18), c = 17.846(4) , β = 101.29(3)o, V = 2438.9(9) 3, Z = 4, Dc = 1.878 g/cm3, T = 193(2) K, C20H30ClCuMo2S4, Mr = 689.60, F(000) = 1376, μ(MoKα) = 2.335 mm–1, S = 1.050, R = 0.0305 and wR = 0.0688 for 4033 observed reflections with I > 2σ(I). In the structure of 2, one [(η5-C5Me5)2Mo2(μ-S)2S2] moiety and one CuCl unit are assembled into an incomplete cubane-like [Mo2S4Cu] core framework, in which the Cu center adopts a distorted tetrahedral geometry coordinated by one μ3-S atom, two μ-S atoms and one terminal chloride. The two Mo…Cu contacts are 2.7519(7) and 2.7689(8) , respectively.  相似文献   

11.
(C_5H_7S_2)_3[Mo_3(μ_3-S)(μ_2-S_2)_3Cl_7]晶体的空间群为Pnam;晶胞参数:a=17.226(4),b=14.306(7),c=15.074(4);z=4,ρ_(obs)=2.03克/厘米~(-3),ρ_(calc)=2.063克/厘米~(-3)。晶体结构由重原子法解出,并经全矩阵最小二乘方精修,偏离因子R值为0.068。研究结果显示出,晶体结构由三核钼簇阴离子[Mo_3(μ_3-S)×(μ_2-S_2 )_3Cl_7]~(3-)以及环绕着它的平面状的阳离子(C_5H_7S_2)~ 所组成。簇阴离子中,三个处在等边三角形顶点的Mo原子,由一个μ_3—S原子将其联系在一起,同时,每两个Mo原子之间还由一个S_2基团桥联,Mo—Mo间距分别为2.755(1),2.755(1),2.743(1)。此外,每个Mo原子还由两个Cl原子配位,使得Mo原子近邻的所有配位原子一起,形成接近五角双锥构型。簇阴离子中还有一个不与Mo原子直接配位的Cl原子,处在三个μ_2—S_2基团之间,而且与这三个S_2的一端S原子有一定程度的成键。簇阴离子整体接近c_(3v)对称性。用Cottonm~([1])等简化量化方法定性地分析了{Mo_3}体系的M—M成键情况,满意地解释了Mo—Mo间距和分子的磁性。  相似文献   

12.
1 INTRODUCTIONTransitionmetalclustercomplexeshavebeenreceivingconsiderableattentioninrecent yearslargelybecauseoftheir potentialapplicationsincatalysisaswellasthenoveltyandversatilityoftheirreactionsandstructures.[1~ 4] Ourinterestinmetalclustercatalysisp…  相似文献   

13.
<正> Introduction. In order to synthesize trinuclear Mo cluster compounds with three bridge-linked acetoxyle groups, we changed the reaction condition described in reference(1) thus obtaining two new cluster compounds with the formula(C_5H_7S_2)[Mo_3(μ_3-O)(μ-X)_3(μ-OAc)_3Cl_3] (referred to beIow as compound (Ⅰ) when X=C1 and compound (Ⅱ) when X=Br). The diffraction work shows that the crystals of these two compounds are isomorphic.  相似文献   

14.
标题配合物是以THF作溶剂,通过(C_5H_5)_2NdCl·ZLiCl和甲基萘钠的还原反应合成的。其晶体属单斜晶系,P 2/c空间群,晶胞参数α=9.235(2)A,b=11.695(2)A,c=20.810(3)A,β=92.88(1)°,Z=2。研究结果表明,标题配合物由相互不相联的〔Li3DME〕~ 和〔(η~5-C_5H_5)_3Nd(μ-H)Nd(η~5-C_5H_5)_3〕~-离子对组成。阳离子中,Li原子与由3个DME提供的6个O原子配位,形成八面体构型,Li—O平均键长为2.116A;阴离子中,2个Nd原子不直接键合,系通过桥H联接,Nd—H=2.19A。此外,每个Nd原子各有3个C_5H_5~-与之配位,Nd—C平均键长为2.812A。  相似文献   

15.
金属-氧簇合物因其结构多样性及在催化、材料和医药等方面的应用而引起人们的关注犤1犦。在众多金属-氧簇合物中,Keggin结构及金属取代Keggin结构金属-氧簇被大量报道,但由于很难获得高质量单晶,有关二帽Keggin结构的报道非常少,目前只有几例报道犤2~9犦。近年来,随着水热法应用到金属-氧簇的合成,陆续获得了一系列具有新颖结构的簇合物。1998年,通过水热法获得了第一个二帽pseudo-Keggin结构簇合物犤NH4犦4H犤PMo8VⅣ4VⅤ2O42犦·24H2O犤10犦。我们用水热法以三乙胺做模板剂获得了一种全新的二帽pse…  相似文献   

16.
(η5-C6H5)2 NbcCH2Si(CH3)3]2 has been prepared and characterized by X-ray diffraction method and solution and frozen-glass EPR.The compound crystallizes in a monoclinic space group P21/O with lattice parameters a=13.291(A),b=12.406(A),σ=13.901A,β=115.40,V=2070A and Z=4 Full-matrix least-squares refinement of the diffractometry data led to final discrepancy indices of K(F0)=0.043,R(F02)=0.057,Rw(F02)=0.071.From computer simulation of the frozen-glass spec trum of the compound,the principal components of the g and T tensors are gx=1.9840.gy=2.0075,gz=2.0020,Tx=-89.2G,Ty=-136.9G,Tz=-50.0G.The observed anisotropy for the hyperfine interaction arises from the admixture of 4dz2 and 4dx2-y2 character in the HOMO.The ratio of mixing coefficients a2/b2=10.3.  相似文献   

17.
[Mo_5P_2O_(23)]~(6-)[(CH_3)_2NH_2]_5~(5+)[H_3O]~+·1/2DMF·1/2H_2O(DMF=(CH_3)_2NC-HO)(M_r=1204.67)的晶体属三斜晶系,空间群P,晶胞参数a=16.438(6);b=22.22(1);c=11.325(5),α=104.25(4);β=108.97(3);γ=97.68(4)°,V=3688(3),Z=4,D_c=2.17gcm~(-1),R=0.056,R_w=0.074,晶胞中每个不对称单元含有两个[Mo_5P_2O_(23)]~(6-)[(CH_3)_2NH_2]_5~(5+)[H_3O]~+·1/2DMF·1/2H_2O,阴离子[Mo_5P_2O_(23)]~(6-)中的Mo、P原子成一个畸变五角双锥构型。有一个阴离子的所有原子(Mo、P、O)位置完全确定,而另一个阴离子有一个磷酸根的三个氧原子位置出现二重位置统计分布。化合物的阳离子为二甲胺阳离子和水合氢离子。  相似文献   

18.
含Ⅵ主族的混合金属原子簇化合物可作为重要的催化剂,这种催化剂在均相催化方面,由于异核原子簇中不同金属具有不同的反应性,可能表现出独特的催化性能,特别是Mo-Fe-S原子簇化合物,除了可作为加氢脱硫的催化剂外,又可能是固氮酶活性中心的模型物,  相似文献   

19.
用MoCl_5和C_ 6H_5COOH(或CH_3C6H_4COOH)在氯苯溶液中反应,得到四钼簇合物Mo_4(μ_3-O)_2O_4Cl_2-(OCOC_6H_5)_6(或[Mo_4(μ_3-O)_2O_4Cl_2(OCOC_6H_4CH_3)_6]·2C_6H_5Cl)晶体。用X射线单晶衍射法测定了簇合物的晶体结构,运用18电子规则及簇合物的晶体结构数据,得到金属Mo-Mo键键价为1,钼在簇合物中均呈+5价。进行了反应机理的探讨,簇合物中端基氧和桥基氧的存在来自于苯甲酸(对甲基苯甲酸),MoCl_5和C_6H_5COOH(CH_3C_6H_4COOH)作用时,首先生成钼的含氧配合物MoOCl_3,然后生成双核钼配合物Mo_2(μ_2-O)_2O_2Cl_2,进一步形成配合物。红外光谱、激光拉曼光谱和磁化率的测定证明了结构分析的结果。值得注意的是,固体表面光电压谱和固体光声光谱的测定,簇合物Mo_4(μ_3-O)_2O_4Cl_2(OCOC_6H_5)_6的表面光电压谱在~600nm处有一光致电荷分离谱带。  相似文献   

20.
[η~3-C_3H_5Fe(CO)_3]_2是由Fe_2(CO)_9和C_3H_5C1在常温下合成得到的。晶体属单斜晶系,空间群为P2_1/n,单胞参数为:a=8.248(1),b=9.021(5),c=9.238(2),β=91.99(1)°,V=686.9(6)°。根据fw=361.9和Z=2计算密度Dcal=1.75g/cm~3。在CAD4四圆衍射仪上用MoKα射线收集了独立衍射数据1643个(I>2σ(I))。[η~3-C_3H_5Fe(CO)_3]_2的晶体和分子结构是用直接法解出,所有非氢原子的坐标参数和各向异性热振动参数经全矩阵最小二乘法修正,最后偏离因子 R_1(F)=0.043。和R_2(F)=0.061,分子具有Ci—1对称性。分子中Fe—Fe距离为3.028,这个数值同Stucky和Muetterties合成的[η~3-C_3H_5Fe(CO)_3]_2中Fe—Fe距离为3.138有明显的差别。  相似文献   

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