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1.
采用1HNMR谱研究了通式为〔M3ⅢO(OOCR)6L3〕+(M=Cr,Fe,Mn;R=CH3,C2H5,CH2NH2;L=C5H5N,H2O)的一系列氧心三核过渡金属配合物,主要考察其1H化学位移随金属、配体、温度、溶剂等因素变化而变化的规律。结果表明,骨架金属对化学位移的影响最大,M3O中的3个金属离子间存在反铁磁交换相互作用。对Mn配合物中顺磁中心对化学位移和线宽的影响机制的研究表明,其1H各向同性位移主要由接触作用贡献  相似文献   

2.
SiO2负载的Pt-M(M=Cr,Mo,W)配合物双功能催化剂   总被引:2,自引:0,他引:2  
过渡金属异双核金属有机化合物的研究是一个活跃的领域,人们期望从中制取对极性小分子(如CO,CO2等)具有双功能活化的催化剂.周期表前区过渡金属或稀土元素(如Ti,Zr,Mo,La,Ce等)作为添加组分可明显地增加SiO2负载的铑催化剂催化CO氢化反应的活性和含氧化合物的选择性[1].虽然一些异双核金属氢基羰基化合物已被合成和表征[2],但是关于SiO2负载的异双核金属配合物催化剂的研究还未见文献报道.我们合成、表征了(PPh3)HPt(μ-PPh2)(μ-CO)M(CO)4(M=Cr,Mo,W)异双核配合物[3](I).本文研究了SiO2负载的该配合物催化剂对CO氢化反应和对丙烯氢甲酰化反应的两种催化功能.  相似文献   

3.
采用1H NMR谱研究了通式为[M3ⅢO(OOCR)6L3]+(M=Cr,Fe,Mn;R=CH3,C2H5,CH2NH2;L=C5H5N,H2O)的一系列氧心三核过渡金属配合物,主要考察其1H化学位移随金属、配体、温度、溶剂等因素变化而变化的规律.结果表明,骨架金属对化学位移的影响最大,M3O中的3个金属离子间存在反铁磁交换相互作用.对Mn配合物中顺磁中心对化学位移和线宽的影响机制的研究表明,其1H各向同性位移主要由接触作用贡献.  相似文献   

4.
在合成和表征了一系列新的异核异价三核过渡金属羧酸配合物〔Fe2 Ⅲ MⅡ O (OOCC2 H5 ) 6 L3〕 (M =Co ,Ni,Mn ;L =C5 H5 N ,H2 O)的基础上 ,利用多种NMR技术并结合UV谱研究了这些配合物在不同溶剂介质和温度下的谱学特征和动力学性质。利用谱峰积分比例、线宽、相同骨架分子的配体取代和纵向弛豫时间对1 HNMR谱进行了归属。实验结果表明 :这类配合物的金属离子间通过中心氧桥存在一定的反铁磁相互作用 ,从而在整体上削弱了顺磁性的影响 ,仍能观察到NMR谱。实验还发现这些配合物在CD3CN和DMSO溶剂中的结构与晶体结构一致 ,而在水中则分解为金属离子、羧酸盐和吡啶。这些结果有助于指导类似配合物的合成  相似文献   

5.
在四氢呋喃-甲醇介质中将环戊二烯基三羰基金属(钼或钨)氯化物与等摩尔羰基亚硝酰基钠盐在室温反应,产物经柱色谱分离和纯化得:橙色固体(η~5-C_5H_5)M(CO)_2NO、紫色固体[(η~5-C_5H_5)M(CO)_3]_2和黑色固体(η~5-C_5H_5)M(μ_3-NH)(μ_2-NO)(μ_2-CO)Fe_2(CO)_6(M=Mo或W)各两种.其中,后者是具有新颖结构的簇合物,分子中含有亚硝酰基(NO)被还原得到的亚胺基(μ_3-NH)配体.本文报道了它们的合成、表征和两种配合物X射线晶体结构研究的结果.  相似文献   

6.
运用G98W,采用Lanl2dz基组,对茂金属配合物[(eat5-C5H4R)Mo(CO)3]2 (R: SiMe3, Si2Me5)进行从头算研究,探讨配合物结构单元的稳定性、分子轨道能量、原子净电荷布居规律,以及一些前沿分子轨道的组成特征等,结果表明,标题配合物结构在能量上是稳定的,作为结构单元而存在.  相似文献   

7.
陈忠  蔡淑惠 《结构化学》2000,19(3):199-206
在合成和表征了一系列新的异核异价三核过渡金属羰酸配合物〖Fe2^ⅢMⅡO(OOCCH2H5)6L3〗(M=Co,Ni,Mn,L=C5H5N,H2O)的基础上,利用多种NMR技术并结合UV研究了这些配合物在不同溶剂介质和温度下的谱学特征和动力学性质。利用谱峰积分比例、线宽、相同骨架分子的配体取代和纵向驰豫时间对^1HNMR谱进行了归属。实验结果表明:这类配合物的金属离子间宫心桥存在一定的反铁磁作用,  相似文献   

8.
合成了离子对配合物(NO2Ql)2犤Ni(mnt)2犦,并用元素分析和红外光谱进行了表征。单晶结构分析结果表明:三斜晶系,空间群P1珔。晶胞参数a=8.2240(16)?,b=10.777(2)?,c=12.137(2)?,α=72.58(3)°,β=72.82(3)°,γ=68.78(3)°,V=935.4(3)?3,Z=1。(NO2Ql) 和犤Ni(mnt)2犦2-分别形成了完全分立的柱状堆积结构。在阴离子堆积柱内,Ni?离子形成了一维均匀链。阳离子间,比邻的芳环间存在弱的π…π作用。  相似文献   

9.
用NMR方法研究了氨三乙氧基乙酸(NTEA)的质子解离过程及其与La3+、Y3+、Lu3+和Ca2+的配合作用.NTEA的氮原子和羧基的质子解离常数分别为8.8和3.0.当pH>3.0时,La3+、Y3+和Lu3+配合物能稳定形成(>50%),而Ca2+配合物则需出>5.在pH3~6范围内,配合物与配体间的交换反应处于慢-中介交换速率区间,通过变温谱模拟得到了其交换反应的动力学参数.  相似文献   

10.
秦金贵 《有机化学》1989,9(5):422-425
H2Se与Cr(η-C5H4Me)2的反应产生了得率高达90%的原子簇化合物[Cr4(μ^3-Se)4(η-C5H4Me)4], 而LiSeH与Mo2(η-C5H4Pr^i)2(μ-Cl)4的反应则产生了其它的簇状化合物[Mo4(μ^3-Se)4(η-C5H4Pr^i)4], 它们都是通过元素分析和H核磁共振谱的研究, X射线单晶体结构分析加强了金属有机原子簇的还原性结构, 循环伏安法数据表明原子簇在溶液中的还原电极电位越低, 其气相第一电离势一般也越小, 光电子谱法研究也表明这些原子簇都具富电子的。  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.
<正> INTRODUCTION. Recently, researches on carbene metal complexes are very active, as they are of great importance in both theoretical study and catalytic activity. In a systematic research, the crystal structure of the title complex was analyzed and reported here to the advantage of understanding the catalytic action and searching for new and better carbene catalysts of novel kinds.  相似文献   

13.
<正> Both of the title complexes were produced by oxidative decarbony-lation of NH4 CMO (CO)5I]. The complexes CMo(S2CNC4H8)4]I3 ?C7H8(1) and Mo2S2O2 (S2CNC4H8)2(2) both crystallize in triclinic, space group P1 with cell dimensions for (1) : a=13. 554(4), b=13. 620(4), c= 13. 058 (4) A , α=95. 58 (3), β=105. 38(2), γ=115. 49(2)°,V = 2035(1) A3, Z=2, Dc=1. 89 g. cm-3, final R=0. 054 and Rw = 0. 062 for 2926 observed reflections; and for (2): a = 8.730(2), b=16.592(6), c = 6. 688(2)A, α=97. 67(3), β=98. 10(2), γ=80. 26(2)% V = 939. 2(5) A3, Z = 2, Dc = 2. 05 g. cm-3, final R = 0. 038 and Rw = 0. 046 for 2248 observed reflections. The Mo(V) atom is bonded to eight S atoms in distorted dodecahedron for (1). The Mo atoms in compound (2) are bridged by two S atoms and each Mo atom is coordinated by two S atoms from S2CNC4H8 and one O atom to form distorted tetragonal pyramid.  相似文献   

14.
<正> The title compound, cyclooctadienyl potassium tetrahydrofuranate was prepared by the reaction of cycloocta-1,5-diene with metallic potassium in tetrahydrof u-ran(THF) in the presence of triethylamine. Its crystal structure was determined by a low temperature X-ray diffraction analysis method. The crystal is monoclinic with space group Pc,a=6. 192(3),b=9. 444(8),c=14. 543(1) A ,β=94. 92(5)°,V = 847. 24 A3,Z = 2,DC= 1. 14 g/cm3 and μ(MoKa) = 5. 58cm-1. The structure was solved by heavy-atom methods and refined by least-squares to a final R value of 0. 049. The potassium cations, each with two complex THF molecules attached,are linked by bridging cyclooctadienyl an-ions,while the anions are connected to the bridging cations to form a puckered chain.  相似文献   

15.
Thetrimolybdenumclusterswithgeneralformula[Mo3(μ3S)(μS)3(μdtp)(dtp)3L](dtp=(S2P(OC2H5)2)-,L=H2O,py,SC(NH2)2etc.)[1](referredtoasM1type[2]),and[Mo3(μ3S)(μS2)3(dtp)3]X(X=Cl,I)[3](referredtoasM2type),aretwomaintypesoftrimolybdenumclusterseverinvestigatedbyourresearchgroup.Aswehavealready…  相似文献   

16.
<正> (Me_4N)[Mo(OC_6H_4S-o)_3] ,Mr=542. 57,orthorhombic,space group Pnb21 with a = 22. 708(1),b = 9. 737(4),c=10. 486(2) A;V=2318. 6A3;Z=4,Dc = 1. 55g/cm3,final R=0. 064 and Rw=0. 074.μ=8. 3cm-1, F(000) = 1108,The atom Mo( V ) of the anion issix-coordinated to three oxygen and three sulfur atoms in a distorted octahedral geometry.  相似文献   

17.
<正> {Mo4S4(μ-OAc)2(dtp)4H}3,(dtp=S2P(OEt)2),Mr=1371.60,Or-thorhombic, space group Pcab, a = 18. 90 (2) ,b = 21. 678 (4 ) , c = 24. 491 (4 ) A , V = 10031(7)A3,Z=8,Dc=1.818g/cm-3,F(000)=5464,λ(MoKa)=0.71073A,finalR= 0. 069 for 3738 independent reflections. This is a successful example of the formation of [Mo4S4]5+ from[3+1] reaction mode. The results of the structure determination indicate that the configuration of the title compound exhibits a tetranuclear cubane-type core [Mo4S4]5+ with six Mo - Mo distances in the range 2. 685~2. 969A and is very similar to that of the previously characterized compound {Mo4S4(μ-OAc)2(dtp)4}2, [Mo4S4]6+, which was obtained directly by the reaction of MoCl3·3H2O with dtp. Some notable differences, however, can be found when six Mo - Mo bond distances and bonding parameters of the four terminal bidentate ligands (dtp) are compared between these two compounds , That can be attributed to the difference in the oxidation state of these two clusters .  相似文献   

18.
<正> Complexes [(η8-C8H8)LnCl(OC4H8)2]2, (Ln = Pr(1), Nd(2)) both crystallize in monoclinic space group P21/n with cell dimensions for 1: a = 11. 860(3), b=12. 697(3), c=12. 161(2)(?), β=111. 88(2)°, V= 1699. 50(69) (?)3, Dc=1. 66gcm-3,Z==2 (4 monomers), μc=30. 2cm-1, F (000) = 848, the final R = 0. 031, Rw = 0. 032 for 2303 independent reflections with I≥ 3σ(I) ; and for 2: a=11. 834(4), b = 12. 666(5), c=12. 166(3)(?), β=111. 73(2)°, V= 1694. 03 (99)(?)3, Dc= 1. 68g. cm-3, Z = 2 (4 monomers), μc=32. 3cm-1, F(000) = 852, R=Rw = 0. 035 for 3487 independent reflections with I≥3σ(I). In each complex, there are two Ln atoms in a dimeric unit which are bridged asymmetrically by two chloride ions with Ln - Cl bond lengths of 2. 847(2) and 2. 924(2)(?) for 1, or 2. 836(1) and 2. 919(2)(?) for 2. The cyclooctatetraene COT dianion ring is planar with eightfold molecular symmetry and an average C -C bond length of 1. 392(?). It is symmetrically coordinated to the Ln atom with an average Ln - C distance of  相似文献   

19.
<正> Introduction. In an attempt to synthesize Mo cluster compounds from the high-valenced Mo compounds in P_2S_5/EtOH-HC1 system we have obtained a brownblack rhombohedral crystal. The composition of it Mo_2O_3[S_2P(OC_2H_5)_2]_4 has been confirmed by X-ray single crystal structure determination, which reveals that the crystal structure is different from that by Knox, J. R. & Prout, C. K. (1969).  相似文献   

20.
黄子祥  卢绍芳 《结构化学》1991,10(3):213-217
<正> Cu8C24H60O12P6S13,Mt= 1651. 73,trigonal,R3,a=b = c= 12. 667(4) A,α= β=γ=111. 42(1)°.V=1441(2)A3,Z=1,Dc=1. 903g·cm-3,λ(MoKa) = 0. 71073 A ,μ(MoKa) = 35. 671cm-1, F ( 000 ) = 830, 293K. Final R = 0. 066,Rw= 0. 077 for 850 unique intensity data (I≥3σ(I)). Each unit cell of the crystal comprises of a neutral molecule of formula Cu8S(dtp)6[dtp=S2P(OEt)2],wherein the eight copper atoms are arranged at the corners of regular cube,with each dtp ligand μ4-bridged to each face of the cube and a μ8-S in the center bonded to all the eight copper atoms. Each copper atom is coordinated by four sulfur atoms in a tetrahedral configuration. The bond lengths of Cu-(μ8-S) are in the range of 2. 627(2)-2. 543(2) A ,those of Cu-S(dtp)in the range of 2. 251-2. 280A.The adjacent Cu-Cu bond lengths (2. 950(5)-3. 070(2) A) show a weak interaction between the copper atoms  相似文献   

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