含金属基团的四价锡化合物的合成和取代反应动力学

通式为[Fe(CO)~2Cp]~2Sn(Ar)Cl的化合物为一组新的化合物,由[Fe(CO)~2Cp]~2SnCl2与AgMgX反应合成.[Fe(CO)~2Cp]~2Sn(Ar)Cl与各种亲核试剂Y发生取代反应给出另一组新的化合物[Fe(CO)~2Cp]~2Sn(Ar)Y,其中[Fe(CO)~2Sn(p-MeC~6H~4)Br经X射线衍射分析确定结构.[Fe(CO)~2Cp]~2Sn(1,3,5-Me~3C~6H~3)Cl与NAS~2CNMe~2或KSCN在不同溶剂中的反应动力学表明,由于锡易形成高配位中间体,尽管锡上两个较大的金属基团带来一定空间障碍,反应仍主要按SN2机理进行.     

呋喃与双卤分子间卤键的电子密度拓扑研究

用DFT和MP2(full)方法研究了呋喃-XY (XY＝ClF, BrF, BrCl)体系分子间的相互作用, 讨论了两种卤键类型 Y—X…O和Y—X…π的作用. 研究表明: Y—X…π的相互作用比Y—X…O的作用强, 计算得到的分子间相互作用能按照呋喃-BrF＞呋喃-ClF＞呋喃-BrCl的顺序依次降低. 形成卤键后, 两种类型卤键复合物中的电子受体X—Y键伸长, 其振动频率发生红移. 利用电子密度拓扑方法对卤键的电子密度拓扑性质进行了分析.     

(Mo_3S_4)_2M~(8+)(M=Mo,Sn,Cu_2)型夹心簇合物的电子结构研究

经对一系列夹心簇合物(H_2O)_9Mo_3S_4MS_4Mo_3(H_2O)_9~(8+)(M=Mo,Sn,Cu_2)的量子化学计算和分析,发现该簇合物是通过配体Mo_3S_4~(4+)中的多中心d-pπ轨道与中心原子键合成簇,其成簇机理与经典的以有机共轭环为配体的夹心配合物十分相似,研究了夹心簇的构型、磁性及电子光谱等性质的分子轨道本质,揭示了多中心d-pπ键的变化与簇合物性质的内在联系。     

Sn(II)―X和Sn(IV)―X (X=O,S, N,C, P,As, Se,Te, F,Cl, Br,I)键价参数

基于剑桥晶体数据库中同配配合物的Sn(Ⅱ)―X和Sn(Ⅳ)―X(X=O,S,N,C,P,As,Se,Te,F,Cl,Br,I)键长数据,采用键价参数B=0.037nm拟合得到Sn(Ⅱ)―X和Sn(Ⅳ)―X的键价参数R0,这样拟合的经验参数R0中有一些是首次推出.本文所报道的Sn(Ⅱ)―O键基于B=0.037nm的R0值(0.1956nm)可适用于多数Sn(Ⅱ)呈各种配位数时的氧化态指定,而文献报道的B=0.055nm和R0=0.1859nm主要对于低配位的情况能取得Sn(Ⅱ)原子价态指定的较好结果.本研究证明,进一步研究键价参数对键价和(BVS)计算至关重要的那些可能的因素实乃当务之急.     

Tb(Co_(1-x)Sn_x)_2合金的结构和磁热效应

通过X射线衍射和磁性测量研究了Tb(Co1-xSnx)2(x=0,0.025,0.050,0.075,0.100)合金的相结构和磁热性能。经分析可知Sn在TbCo2中的替代是有限的,X粉末衍射分析确定TbCo2具有MgCu2结构,其他样品由TbCo2,TbCo3和Tb5Sn3三相组成,TbCo2为主要相。随着Sn成分的增加,杂质相TbCo3和Tb5Sn3的含量增加,所有样品保持第二序磁相变。Sn的替代使磁相变的温度稍微有所提高,样品TbCo2的TC值为230 K,样品Tb(Co0.950Sn0.050)2的TC值为233 K,但Sn的成分继续增加,样品的TC值有所下降。在外加磁场2 T的作用下,样品Tb(Co1-xSnx)2(x=0,0.025,0.050,0.075)最大磁熵变值分别为3.44,2.29,1.64,1.16 J.kg-1.K-1。     

具有新颖嵌合作用的金属配合物的微波合成、晶体结构及性质研究

在微波辐射条件下合成了两种新的离子液体金属配合物[Ni(m-HNDA)2(H2O)4](1),[Zn(m-HNDA)2(H2O)4]·H2O(2),用元素分析、红外光谱、紫外光谱对它们进行了表征,通过X射线单晶衍射测定了它们的晶体结构.在晶体结构中,标题物通过基团间的嵌合作用,π-π相互作用和分子间氢键自组装成了三维网状的多孔结构.由氢键和π-π相互作用的强弱推测标题物的稳定性次序2>1,与实测热稳定性次序完全吻合;电化学性质表明,金属的配位改变了配体的循环伏安性质.另外,两种配合物可在水溶液中高选择性的识别氟离子.     

Synthesis and Characterization of Diorganotin Compounds {[R2Sn（ON =CHC6H5）]2O}2 and Crystal Structure of {[（C6H5CH2）2Sn（ON=CHC6H5）]2O}2

Introduction Dimeric tetraorganodistannoxanes are a kind of in-teresting organotin oxo clusters and have attracted con-siderable attention during the last several decades, in view of their unique structural features1-5 as well as their applications as biocides6,7 and in homogenous cataly-sis.8,9 In the solid state, they contain characteristic Sn4O2X2Y2 structural motifts with staircase or ladder arrangements, a planar four-membered Sn2O2 ring and, generally, penta-coordination around the tin…     

密度泛函理论在分子磁学中的应用

通过对桥联双核铁的磁耦合常数的计算，探讨了密度泛函理论计算条件对计算 结果的影响。基于密度泛函理论下的破损态方法，着重讨论了双核 Fe(III)_2的 d~5-d~5电子通过氧桥的超交换作用。研究发现分子的反铁磁通道主要是Fe(III) d_yz和d_z~2与μ-O的p轨道形成的，具有π*/π*和σ*/σ*特征的超交换通道。     

密度泛函理论在分子磁学中的应用

通过对桥联双核铁的磁耦合常数的计算，探讨了密度泛函理论计算条件对计算 结果的影响。基于密度泛函理论下的破损态方法，着重讨论了双核 Fe(III)_2的 d~5-d~5电子通过氧桥的超交换作用。研究发现分子的反铁磁通道主要是Fe(III) d_yz和d_z~2与μ-O的p轨道形成的，具有π*/π*和σ*/σ*特征的超交换通道。     

基于八配位铁的化合物(H2prz)[Fe(bpdc)2]·3H2O的合成、晶体结构及磁性质

通过水热方法,采用H2bpdc(H2bpdc=2,2′-bipyridine-6,6′-dicarboxylic acid)和prz(prz=piperazine)与FeSO4.7H2O反应,合成了一个质子传递化合物(H2prz)[Fe(bpdc)2].3H2O(1),并对其结构、热稳定性和磁性质进行了研究。结构分析结果表明该化合物的晶体属于单斜晶系,P21/n空间群。该化合物的分子由1个[Fe(bpdc)2]2-阴离子,1个H2prz2+阳离子和3个水分子组成。其中,Fe原子采取了少见的八配位畸变的十二面体构型。这些化合物分子通过分子间的氢键和π-π堆积作用形成了1个三维的超分子框架。     

固相配位化学反应研究 XXIII: 一取代基五氰合铁(II)类配合物热分解反应的研究

本文以气相色谱法为主要手段, 配合Mossbauer谱、红外光谱等结构分析方法, 研究了一系列一取代基五氰合铁(II)类配合物Na2[Fe(CN)5L]·mH2O及Na3[Fe(CN)5L']·nH2O(L=NO^+、N2H5^+、enH^+, L'=NH3、H2O、Py)的热分解反应。结果表明所有一取代五氰合铁(II)配合物热分解过程中都形成相同的中间化合物Na4[Fe(CN)6]和Fe2[Fe(CN)6], 各配合物热分解放出取代基L(L')的温度次序与L(L')在光谱化学序列中的次序一致。本文以亚硝基铁氰化钠为代表, 详细讨论了该系列配合物的热分解反应机理以及热稳定性的规律性。     

Schiff碱配合物的研究II: 一些Fe(III)配合物的磁性质与电化学行为

Fe(III)schiff碱配合物的磁性质和电化学还原性是该类配合物的基本特性, 本文研究三种配合物, 单核高自旋配合物, 单核低自旋配合物以及氧桥双核配合物的核磁共振性质电化学还原性。     

双(π-芳烃)铁(II)化合物的Mossbauer分析

铁的简单配合物及羰基化合物的Mossbauer研究已有报道, 对有机铁化合物的相应工作进行得较少. 本文报道一类具有夹心结构的有机铁化合物的^5^7FeMossbauer参数及其与结构的一些关系.     

一些含半夹心结构VIB族金属的1, 1'-二硫(硒)二茂铁化合物的 合成

Cp^*Cr(NO)(CO)~2与Fe(C~5H~4S)~2S反应,形成氧化-还原产物Cp^*Cr(NO)(SC~5H~4)~2Fe(1)。双杂核二茂铁化合物Cp^*M(NO)(EC~5H~4)~2Fe[M=Mo,E=S(2a),Se(2b);M=W,E=S(4a),Se(4b)]、CpMo(NO)(SC~5H~4)~2Fe(3)、Cp~2Mo(SeC~5H~4)~2Fe(6)和Cp~2W(SC~5H~4)~2Fe(7)可通过Fe(C~5H~4ELi)~2.2THF(E=S,Se)与Cp^*M(NO)I~2(M=Mo,W)、[CpMo(MO)I~2]~2或Cp~2MCl~2(M=Mo,W)反应制得。三核杂原子二茂铁化合物[Cp^*Cr(NO)~2]~2(EC~5H~4)~2Fe[E=S(8a),Se(8b)],由Fe(C~5H~4ELi)~2.2THF(E=S,Se)与二倍摩尔量的Cp^*Cr(NO)~2I反应制备。通过AgBF~4氧化2a得到二茂铁离子型化合物[Cp^*Mo(NO)(SC~5H~4)~2Fe]^+BF~4^-(5)。采用元素分析、红外光谱、^1H和^1^3CNMR谱以及EI-MS表征了所合成的新型化合物。     

斯德酮化全物的反应

用3-苄基-4-苯基斯德酮和4-甲酰基-3-芳基斯德酮的硝化研究了在斯德酮环4-取代的去定域化效应和斯德酮环的电子效应的二重性。     

Spectroscopic and physicochemical studies on nickel(II) complexes of isatin-3,2'-quinolyl-hydrazones and their adducts

Nickel(II) complexes of isatin-3,2'-quinolyl-hydrazones of the type [Ni(L)X] (where X=Cl-, Br-, NO3-, CH3COO- and ClO4-] and their adducts Ni(L)X.2Y [where Y=pyridine or dioxane and X=Cl-, Br-, NO3- and ClO4-] have been synthesized under controlled experimental conditions and characterized by using the modern spectroscopic and physicochemical techniques viz. mass, 1H NMR, IR, electronic, elemental analysis, magnetic moment susceptibility measurements and molar conductance, etc. On the basis of spectral studies a four coordinated tetrahedral geometry is assigned for Ni(L)X type complexes whereas the adducts (Ni(L)X.2Y) were found to have a six coordinated distorted octahedral geometry.     

Building blocks for coordination polymers: self-assembled cleft-like and planar discrete metallo-macrocyclic complexes

Discrete dinuclear metallo-macrocyclic complexes have been prepared from the flexible amide ligand N-6-[(3-pyridylmethylamino)carbonyl]pyridine-2-carboxylic acid (L1-CH(3)), and its more rigid analogue, N-6-[(3-pyridylamino)carbonyl]pyridine-2-carboxylic acid (L3-CH(3)). With ligands L1-CH(3) and L3-CH(3), discrete dinuclear metallo-macrocyclic complexes with the generic formula [Cu(2)(L1-CH(3))(2)(X)(2)(Y)(2)] (7, X = NO(3); 8, X = Cl, Y = H(2)O; 9, X = ClO(4), Y = CH(3)OH) and [Cu(2)(L3-CH(3))(2)(X)(2)(Y)(2)] (10, X = NO(3), Y = H(2)O; 11, X = ClO(4), Y = CH(3)OH) are obtained. For complexes 7-9, containing the more flexible link L1-CH(3), these complexes are cleft-shaped and hinged at the methylene spacer, which allows the cleft to widen and contract to accommodate different packing modes in the solid-state. In contrast, the rigid link L3-CH(3) gives near planar metallo-macrocyclic structures. These metallo-macrocyclic compounds may be useful building blocks for coordination polymers.     

Spectroscopic approach in the characterization of the copper(II) complexes of isatin-3,2'-quinolyl-hydrazones and their adducts

Copper(II) complexes of isatin-3,2'-quinolyl-hydrazones of the type [Cu(L)X] (where X=Cl(-), Br(-), NO(3)(-), CH(3)COO(-) and ClO(4)(-)] and their adducts Cu(L)X.2Y [where Y=pyridine or dioxane and X=Cl(-), Br(-), NO(3)(-) and ClO(4)(-)] have been synthesized under controlled experimental conditions and characterized by using the modern spectroscopic and physicochemical techniques viz. IR, electronic, EPR, elemental analysis, magnetic moment susceptibility measurements and molar conductance, etc. On the basis of spectral studies a four coordinated square planer geometry is assigned for Cu(L)X type complexes whereas the adducts (Cu(L)X.2Y were found to have a six coordinated octahedral geometry.     

Synthesis and self-association, absorption, and fluorescence properties of differentially functionalized hexakis(p-substituted-phenylethynyl)benzenes

The dual Sonogashira coupling reactions of 1,3,5-tribromo-2,4,6-triiodobenzene with p-X-phenylacetylene followed by another p-Y-phenylacetylene (X, Y = OSiMe(2)Bu-t or CO(2)Et) produced a series of differentially functionalized hexakis(p-substituted-phenylethynyl)benzenes with D(3)(h)() symmetry (3h: 1,3,5-X-2,4,6-Y) and C(2)(v)() symmetry (3g,i: 1,2,3,5-X-4,6-Y; 3f,j: 1-X-2,3,4,5,6-Y). In a similar manner, 1,3,5-tris(p-X-phenylethynyl)-2,4,6-tris(p-Y-phenylethynyl)benzenes and 1,2,3,5-tetrakis(p-X-phenylethynyl)-4,6-bis(p-Y-phenylethynyl)benzenes (3l: X = OSiMe(2)Bu-t, Y = NO(2); 3m,n: X = N(n-octyl)(2), Y = NO(2); 3o,p: X = N(n-octyl)(2), Y = CH(OCH(2)CH(2)O); 3q,r: X = N(n-octyl)(2), Y = CHO; 3s,t: X = N(n-octyl)(2), Y = CH=C(CN)(2)) were prepared. Compounds 3 with electron-withdrawing groups self-aggregated by a pi-pi stacking interaction and solvophobic effect. In the absorption and fluorescence spectra of 3, lambda(max)(abs) and lambda(max)(em) showed red shifts as the donor-acceptor dipole at the end functional groups of the para position was increased. In the absorption spectra, lambda(max)(abs) showed red shifts upon increasing the number of combination of electron-donating and -withdrawing groups on the diagonal line in a molecule, whereas lambda(max)(em) in the fluorescence spectra exhibited red shifts upon decreasing the molecular symmetry.     

K5LnLi2F10(Ln=La,Gd, Y)的合成和Ce^3^+在其中的发光

在Ar气氛中, 采用高温固相反应法合成了K5LnLi2F10(Ln=La, Ce, Gd, Y)化合物,X射线衍射图表明: 除K5YLi2F10外, 均具有与K5NdLi2F10(KNLF)相同的结构。计算了K5LnLi2F10(Ln=Ln, Ce, Gd)的晶胞参数和晶胞体积, 它们随着La^3^+, Ce^3^+,Gd^3^+的离子半径减小而有规律地减小, 测定了K5CexLn1-xLi2F10化合物的激发光谱和荧光光谱, 发现Ce^3^+的激发波长和发射波长随着La^3^+, Gd^3^+, Y^3^+离子的改变几乎不变, 并对这种现象进行了讨论。