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1.
<正> INTRODUCTION. More and more models of active center were suggested with wide study on the MoFe-protain and FeMo-cofactor of nitrogenase. Most of them contain MFe_3S_(3+4) (M=Mo,Fe) cubane-type core, so a great interest has been focused on the Studies of MoFe_4, cubane-type compounds. The type species have been reported by holm et al. We have also made researches on the single cubane-like compounds. Here we describe the synthesis and structure of [MoFe_3S_4(Et_2dtc)_5MeCN (1).  相似文献   

2.
Single cubane-like clusters, MFe_3S_4(R_2dtc)_5 (M=Mo, R_2=—(CH_2)_4—, Bz_2; M=W, R_2=Me_2, —(CH_2)4—; dtc=dialkyldithiocarbamate) were synthesized by assembly reaction of (NH_4)_2MS_4 (M=Mo, W), FeCl_2 with R_2dtcNa (or NH_4) in DMF. The structure, IR, EPR and cyclic voltammogram are described and discussed. MoFe_3S_4(C_4H_8dtc)_5 was also obtained from the conversion of linear cluster Fe(DMF)_6[(FeCl_2)_2MoS_4] in the presence of C_4H_8dtc NH_4. Both clusters MoFe_3S_4(C_4H_8dtc)_4·2C_2H_5CN and WFe_3S_4(C_4H_8dtc)_5·2DMF crystallize in the monoclinic space group C2/c with a=12.544(2), (Mo-cluster), 12.533(4) (W-cluster); b=20.478(4), 20.121(6); c=19.582(7), 19.659(2);β=102.82(2), 102.96(3)°; and Z=4, 4. Their structures were refined to R=0.057 and 0.064 with use of 2690 and 2179 reflections (ι>3Q(I)), respectively. Many similarities in structure for Mo and W clusters indicate that both Mo and W play a very similar role in the clusters.  相似文献   

3.
六氢吡啶基二硫代甲酸钠盐、氯化亚铁及四硫代钼酸铵在二甲基甲酰胺及二氯甲烷中,经一步自兜反应,分别得到了[MoFe_3S_4(C_5H_(10)NCSS)_5]DMF及[MoFe_3S_4(C_5H_(10)NCSS)_5]CH_2Cl_2。通过X射线衍射测定了后者的晶体结构,比较了它与[MoFe_3S_4(Et_2NCSS)_5]~-结构特点的异同,同时研究了反应物摩尔比对产物的影响以及溶剂分子的置换反应。  相似文献   

4.
Activity on catalytic reduction of C_2H_2 for seven Mo-Fe-S cluster compounds (I. (Et_4N_4)_4[Mo_2Fe_2S_(10)]·2CH_3OH, Ⅱ. Mo_2Fe_2S_4(S_2CNEt_2)_5·CH_3CN, Ⅲ. (Bu_4N)_3 [Mo_2FeS_8O]·Ⅳ·(Et_4N)_3[Mo_2FeS_8O_2], V. (Et_4N)_2[MoFeS_4(SCN)_2(OCH_3)_2]·3CH_3OH, Ⅵ. (Et_4N)_3[Mo_2FeS_8O(OCH_3)_2], Ⅶ. (Et_4N)_4Mo_2Fe_7S_(12)(SPh)_6·6CH_3OH), three Fe-S cluster compounds (Ⅷ.(Et_4N)_2[Fe_4S_4(S_2CNEt_2)_4], Ⅸ. (Bu_4N)_2[Fe_4S_3(SC(CH_3)_3)_4], Ⅹ. (Bu_4N)[Fe_2S_3(SCH_2Ph)_2]) and combination systems of related compounds, has been determined under anaerobic conditions at 25℃ and with KBH_4 as the reductant. In addition, at 15℃, under otherwise the same conditions, activity on catalytic reduction of C_2H_2 for different constituent systems from (NH_4)_2MoS_4 and FeCl_3 has also been determined.  相似文献   

5.
The reaction of Mo(0) complex [Mo(CO)_4(S_2CNEt_2)]~- with phenthiolate [Et_4N]SΦin acetonitrilo in the presence of small amount of air affords a new oxo-molybdenum com-plex [MoO(SΦ)_2(S_2CNEt_2)]~-,which crystallizes in two forms of crystals,[Et_4N][MoO(SΦ)_2(S_2CNEt_2)](1a) and [Et_4N][MoO(SΦ)_2(S_2CNEt_2)]·(CH_3)_2CHOH (1b).The structures of1a and 1b were determined from three-dimensional X-ray data.1a crystallizes in the mo-noclinie,space group C_c with a=12.321(4),b=15.245(4),c=16.087(9);β=98.44(4)°.V=2989~3,Z=4,D_c=1.35 g/cm~3 and R=0.031 for 2434 reflections [I>3(I)].1b crystallizes inthe monoclinic,space group P2_1/n with a=9.861(1),b=20.357(3),c=17.122(5)A;β=92.27(2)°,V=3434.3~3,Z=4;D_c=1.29 g/cm~3 and R=0.051 for 2852 independeut reflections [I>3σ(I)],The structures of 1a and 1b reveal that the anion [MoO(SΦ)_2(S_2CNEt_2)]~- contains asingle oxo ligand coordinating to a molybdenum(Ⅳ) and the geometry around Me(Ⅳ) atomis a distorted square pyramid.Interestingly,the solvate molecule isopropanol of 1b is linkedto oxo group by a hydrogen-bond of 1.928A,leading to the increase of Mo=O bond distance(1.718).Mo—S distances are 2.44 and 2,39.The electrochemical behavior of 1 wasdiscussed also.  相似文献   

6.
具[MoFe_3S_4]类立方烷结构单元的双类立方烷化合物[Et_4N]_4[Mo_2Fe_7S_8(SR)_(12)](1a,R=Ph;1b,R=tolyl-m)或单类立方烷化合物[MoFe_3S_4(dtcR_2)_5](2a,R=Me;2b,R=Et)与酰氯在乙腈中反应,分别得到不含Fe桥的双类立方烷化合物(Et_4N)_3[Mo_2Fe_6S_8(SR)_3Cl_6](3a,R=Ph;3b,R=tolyl-m)与[MoFe_3S_4]骨架支解后的Fe(dtcR_2)_2Cl(4a,R=Me;4b,R=Et)。说明在相同反应条件下,[MoFe_3S_4]单元在1中比在2中稳定。本文首次将1型与3型结构通过一步化学反应连系起来。3型化合物的产生得到X射线衍射测定及~1H NMR谱的证实。本文报道3b的单晶结构及3的~1H NMR数据。3b属六方晶系,P6_3/m,a=1.6827(3),c=1.5951(16)nm;V=3.91158nm~3;D_c=1.491g/cm~3;Z=2;F(000)=1780;偏离因子R=0.048。化合物2与酰氯反应产生4,由红外及紫外可见光谱证实。  相似文献   

7.
双齿含硫配位体,二乙胺基二硫代甲酸钠盐与氯化亚铁及四硫代钼酸铵在二甲基甲酰胺溶液中,经一步自兜反应得到(Et_4N)[MoFe_3S_4(Et_2NCSS)_5]CH_3CN(1).X射线单晶结构测定表明1具有类立方烷骨架,核心价态为[MoFe_3S_4]~(4+),通过对1的阴离子结构分析,指出配位基的双齿螯合作用对化合物的稳定性及结构的影响.化学键理论计算也解释了阴离子中的主要键长特点.  相似文献   

8.
The compound(n-Bu_4N)_2[W_2Cu_4S_8(S_2CNC_4H_8)_2]was obtained by the reaction of Bu_4NBr,(NH_4)_2WS_4,NaS_2NCC_4H_8 and CuCl in CH_3CN and CH_3OH.It crystallizes in the monoclinicspace group P2_1/c with unit cell parameters:a=21.875(5),b=16.843(4),c=17.745(5),β=101.69(6)°,V=6402(6)~3,Z=4,D_o=1.718 g·cm~(-3).The final R and R_w values converged to 0.055and 0.060 respectively.The structure consists of two‘butterfly’units[WS_4Cu_2]linked togetherby two weak Cu—S bonds and two bridging S_2CNC_4H_8 ligands.Infrared spectra gave charac-teristic absorptions at 495 cm~(-1) for W=S and 450,435,412 cm~(-1) for W—μ-S.  相似文献   

9.
以Fe(DMF)_6[(FeCl_2)_2MoS_4]与Et_2NCS_2Na在DMF中反应实现了三核链状簇骼向单立方烷簇骼的转化,得到了MoFe_3S_4(Et_2NCS_2)_5并测定了它的晶体结构.本文指出与配体有关的氧化还原过程及配体的配位特点对这一转化反应及其产物的影响,同时比较了由于核心氧化态的差异而造成的簇骼结构面貌的变化.  相似文献   

10.
<正> The compound [Et_4N]_2[Fe_2S_2(NO)_4] (M_r=556.36) crystallizes in the monoclinic,space group P 2_1/n with a=9. 688(3), b=10. 882(2), c=12. 625(2), β=97. 86(3)°, Z=2, V=1318. 4, D_c=1. 40g/cm~3, ;μ(MoK_a)=12. 8cm~(-1) and F(000)=588. The final R=0. 028 and R_w=0. 029 for 2041 reflections (I≥3σ(I)).The crystals of [Et_4N]_2[Fe_2S_2(NO)_4] consist of discrete cations [Et_4N]~+ and anions  相似文献   

11.
本文报道了标题簇合物的快原子轰击质谱(FAB—MS)研究,提出了标题簇合物质谱的可能断裂途径及其结构相关性。指出标题簇合物的FAB—MS与电子轰击谱(EI—MS)所表现的两种迥然不同的断裂模式。观察到单立方烷缺一个顶点和缺二个顶点的碎片离子如[WFe_2S_3(S_2CNC_4H_8)_2]~+、(MoFe_2S_3(S_2CNC_4H_8)_3]~+和[WFeS_3(S_2CNC_4H_8)_3]~+、[MoFe_3S_3(S_2CNC_4H_8)_2]~+等,而后者的簇芯(MoFe_3S_3)结构具有缺口的立方烷状构型特点,是目前合成工作者期待合成但尚未合成出的一种固氮模型物。  相似文献   

12.
The cluster compound[Mo_4S_4(μ-O_2CC_5H_5)_2(dtp)_4](dtp=S_2P(OEt)_2)wasobtained by the ligand substitution reaction of tetranuclear molybdenum cluster[Mo_4S_4(μ-dtp)_2(dtp)_4]in the mixed solvent of acetone,ethanol and water in thepresence of C_6H_5CO_2Na.It is monoclinic and crystallizes in space group C2/c,Mr=1495.09,a=12.175(5),b=22.01(1),c=20.875(9),β=99.04(4)°;V=5575(5);Z=4;Dc=1.78g/cm~3.Final R factor is 0.066.The result reveals that the[Mo_4S_4]clustercore and t-(dtp)~(-1)ligands are retained and only μ-bridged(dtp)~(-1)ligands aresubstituted by(C_6H_5CO_2)~(-1)in the substitution reaction,thus producing the newtitle cluster compound,the structure of which contains two species of bidentateligand.  相似文献   

13.
IR and NMR spectra of novel bionics insecticide—C_5NS_4O_6H_(12)Na·H_2O have been studied. The molecular and crystal structures of the compound also have been determined. The compound crystallizes in the monoclinic space group C_(2h)~5, - P2_1/n with α= 8.0972. (9) , b =16.262(4), c = 10.370(3), β= 94.26(2)° and z = 4.The result shows that N atom in this compound captures a proton to form HN~ group, Na~ is in statistical disorder. Therefore, the structural formula of tho compound is (CH_3)_2HN~ —CH(CH_2S_2O_3~-)_2·1/2 (Na~ )_2·H_2O.  相似文献   

14.
The crystal structure of two isomorphic cluster compounds with formula (C_5H_7S_2)-[Mo_3(μ_3-O)(μ-X)_3(μ-OAc)_3Cl_3] (X=Cl for compound (Ⅰ) and compound (Ⅱ)) has been investigated by X-ray diffraction method. The parameters of two crystals are: a=10.423(1),b=17.095(4), c=14.062(7), β=97.54(4)(°); Dc=2.20gcm~(-3), D_o=2.17g cm~(-3) for compound (Ⅰ). and a=10.511(3), b=11.213(2), c=14.053(3), β=96.12(2)(°); D_c=2.52g cm~(-3), D_o=2.53gcm~(-3) for compound (Ⅱ). The space groups are P2_1/C. Z=4. The 2621 and 2548 independent reflections with I>3σ(I) were collected on a CAD-4 four-circle diffractometer by means of MoKα radiation. The crystal structures were solved by heavy atom method and refined by full-matrix least-squares technique to a final discrepancy factors of R=0.061 and 0.051 respectively. The results of investigation show that the molecule consists of the cation (C_5H_7S_2)+ and the trinuclear Mo cluster anion, the configuration of which is similar to that of (Et_4N)_2[Mo_3(μ_3-O)(μ  相似文献   

15.
在二甲胺基二硫代甲酸钠、氯化亚铁及四硫代钼酸铵的自兜反应体系中,以分步结晶法分离出MoFe_3S_4(Me_2NCS_2)_5·CH_2Cl_2及 MoFe_3S_4(Me_2NCS_2)_6·2CH_3CN 等单立方烷簇合物,并测定了后者的结构.它的分子含两个 Me_2NCS_2桥,并具有最高核心氧化态[MoFe_3S_4]~(6+).本文报道该化合物的结构特点,指出在自兜反应体系中,可能存在几种不同氧化态的单立方烷原子簇化合物.  相似文献   

16.
The reactions of diorganotin dichloride [Ph_2SnCl_2, (PhCH_2)_2-SnCl_2 or (n-Bu)_2SnCl_2] with potassium salt of 2,5-dimercapto-4-phenyl-1, 3, 4-thiodiazole gave complexes R_2Sn (S_3N_2C_8H_5)_2(4: R=Ph; 5: R=PhCH_2 and 6: R=n-Bu), respectively.Characterizations were carried out for all complexes by IR, ~1HNMR spectra and X-ray crystallography analysis. Including theSn…N interaction, the three complexes all have six-coordinateddistorted octahedral geometry. Based on the requence of stereo-chemical constraint sequence, phenyl≈benzyl>n-butyl, the lessthe effect of the stereochemical constraint of R groups, the  相似文献   

17.
A new trithiocarbonato Mo complex(Et_4N)_2[(S_2)Mo2O_2(μ-S)_2(CS_3)]was obtained from asystem containing MoO_4~(2-),S_x~(2-),and CS_2 and characterized by IR and X-ray structural analysis.The complex crystallizes in the (?)onoclinic space group P2_1/c with a=9.539(3)(?),b=20.745(2)(?),c=15.452(2)(?),β=94.58(2)°,and Z=4.The structure was solved by direct anddifference Fourier synthesis methods.Least squares refinement using 2910 reflections withI>3σ(I)converged to R=0.054.The CS_3~(2-) iigand in the complex chelates to Mo atom andvalues of the C-S bond distances in the CS_3~(2-) ligend indicate a substantial contribution ofthree resonance forms.  相似文献   

18.
In this paper, a new complex {Mo[S_2CN(C_2H_5)_2]_4}~( 1){FeCl}~(-1){C_6H_5CH_2SSCH_2C_6H_5} is syn-thesized by the reaction of MoCl_5, FeCl_3, PhCH_2SH and diethyldithiocarbamate (DTC)in MeOH. The complex is characterized by X-ray, IR, UV-visible, reflection spectra, themeasurements of magnetic susceptibility, differential thermal and elemental analyses. The crystal of triadic complex containing multi-bond species is quite stable and rare.  相似文献   

19.
This paper presents a character table of S_4 wr S_2 wreathproduct group.Using this character table,~1H or ~(13)C NMR spectra analysisof molecula with S_4[S_2]symmetry,especially simplification of the seculardeterminant equation will be easy to carry out.Molecules with S_4[S_2]symmetry,are exemplified by octaphenylcyclo-tetrasiloxane and 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine chromium(Ⅲ)chloride.  相似文献   

20.
The features of synthetic processes are described on the basis of the studies of the syntheses of MoFe_3S_4 cubane-like cluster compounds either by self-assembly reactions or by the conversion of linear clusters. The redox properties and the structure of ligands as well as the stoichiometry of reactants have obvious effects upon the core oxidation state and the structure of products. It is indicated that the self-assembly reaction may pass through a combination process oflinear cluster intermediates having structural unit (M,M'=Mo) Fe).  相似文献   

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