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1.
The reaction of CuX(2) (X(-) ≠ F(-)) salts with 1 equiv of 3-pyridyl-5-tert-butylpyrazole (HL) in basic methanol yields blue solids, from which disk complexes of the type [Cu(7)(μ(3)-OH)(4)(μ-OR)(2)(μ-L)(6)](2+) and/or the cubane [Cu(4)(μ(3)-OH)(4)(HL)(4)](4+) can be isolated by recrystallization under the appropriate conditions. Two of the disk complexes have been prepared in crystalline form: [Cu(7)(μ(3)-OH)(4)(μ-OCH(2)CF(3))(2)(μ-L)(6)][BF(4)](2) (2) and [Cu(7)(μ(3)-OH)(4)(μ-OCH(3))(2)(μ-L)(6)]Cl(2)·xCH(2)Cl(2) (3·xCH(2)Cl(2)). The molecular structures of both compounds as solvated crystals can be described as [Cu?Cu(6)(μ-OH)(4)(μ-OR)(2)(μ-L)(6)](2+) (R = CH(2)CF(3) or CH(3)) adducts. The [Cu(6)(μ-OH)(4)(μ-OR)(2)(μ-L)(6)] ring is constructed of six square-pyramidal Cu ions, linked by 1,2-pyrazolido bridges from the L(-) ligands and by basal, apical-bridging hydroxy or alkoxy groups, while the central Cu ion is bound to the four metallamacrocyclic hydroxy donors in a near-regular square-planar geometry. The L(-) ligands project above and below the metal ion core, forming two bowl-shaped cavities that are fully (R = CH(2)CF(3)) or partially (R = CH(3)) occupied by the alkoxy R substituents. Variable-temperature magnetic susceptibility measurements on 2 demonstrated antiferromagnetic interactions between the Cu ions, yielding a spin-frustrated S = (1)/(2) magnetic ground state that is fully populated below around 15 K. Electrospray ionization mass spectrometry, UV/vis/near-IR, and electron paramagnetic resonance measurements imply that the heptacopper(II) disk motif is robust in organic solvents.  相似文献   

2.
自1969年首次报道稀土环辛四烯基化合物Eu(C_8H_8)和Yb(C_8H_8)的合成以来,相继合成K[Ln(C_8H_8)_2],[Ln(C_8H_8)Cl·2THF]_2和[Ln(C_8H_8)·2THF]等,还报  相似文献   

3.
Dinuclear non-heme iron clusters containing oxo, hydroxo, or carboxylato bridges are found in a number of enzymes involved in O(2) metabolism such as methane monooxygenase, ribonucleotide reductase, and fatty acid desaturases. Efforts to model structural and/or functional features of the protein-bound clusters have prompted the preparation and study of complexes that contain Fe(micro-O(H))(2)Fe cores. Here we report the structures and spectroscopic properties of a family of diiron complexes with the same tetradentate N4 ligand in one ligand topology, namely [(alpha-BPMCN)(2)Fe(II)(2)(micro-OH)(2)](CF(3)SO(3))(2) (1), [(alpha-BPMCN)(2)Fe(II)Fe(III)(micro-OH)(2)](CF(3)SO(3))(3) (2), and [(alpha-BPMCN)(2)Fe(III)(2)(micro-O)(micro-OH)](CF(3)SO(3))(3) (3) (BPMCN = N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)-trans-1,2-diaminocyclohexane). Stepwise one-electron oxidations of 1 to 2 and then to 3 demonstrate the versatility of the Fe(micro-O(H))(2)Fe diamond core to support a number of oxidation states with little structural rearrangement. Insight into the electronic structure of 1, 2', and 3 has been obtained from a detailed M?ssbauer investigation (2' differs from 2 in having a different complement of counterions). Mixed-valence complex 2' is ferromagnetically coupled, with J = -15 +/- 5 cm(-)(1) (H = JS(1).S(2)). For the S = (9)/(2) ground multiplet we have determined the zero-field splitting parameter, D(9/2) = -1.5 +/- 0.1 cm(-)(1), and the hyperfine parameters of the ferric and ferrous sites. For T < 12 K, the S = (9)/(2) multiplet has uncommon relaxation behavior. Thus, M(S) = -(9)/(2) <--> M(S) = +(9)/(2) ground state transition is slow while deltaM(S) = +/-1 transitions between equally signed M(S) levels are fast on the time scale of M?ssbauer spectroscopy. Below 100 K, complex 2' is trapped in the Fe(1)(III)Fe(2)(II) ground state; above this temperature, it exhibits thermally assisted electron hopping into the state Fe(1)(II)Fe(2)(III). The temperature dependence of the isomer shifts was corrected for second-order Doppler shift, obtained from the study of diferrous 1. The resultant true shifts were analyzed in a two-state hopping model. The diferric complex 3 is antiferromagnetically coupled with J = 90 +/- 15 cm(-)(1), estimated from a variable-temperature M?ssbauer analysis.  相似文献   

4.
Selective dimetalation of a sandwich complex featuring the cyclooctatetraene ligand has been accomplished for the first time. The isolation of the dilithiated species 1 subsequently enabled the isolation of a paramagnetic [2]stannatitanoarenophane (2) via salt elimination reaction. Chemical oxidation resulted in the formation of a rare example of a cationic ansa-complex (3).  相似文献   

5.
SCHUMANN  H.  DIETRI  孙俊全 《有机化学》1993,13(5):523-527
本文用(C~8H~8)Y(μ-Cl)(THF)]~2与NaOC~6H~5以1:2摩尔比在四氢呋喃中反应, 合成了新的中性配合物[(C~8H~8)Y(μ-OC~6H~5)(THF)]~2, 经过分离, 在-30℃下培养得到无色晶体, 用元素分析, 核磁共振和质谱进行了鉴定, 并以X-射线衍射测定了晶体结构。  相似文献   

6.
采用浓硫酸对白杨素进行磺化,磺化产物与Ca(Ⅱ)络合,合成了结构新颖的四核钙配位标题化合物[{Ca(C15H8O7S)(H2O)(DMSO)}3{Ca(C15H8O7S)(DMSO)2}]·4DMSO.采用IR,1HNMR和X射线单晶衍射法对其进行了表征和晶体结构测定.标题化合物属于三斜晶系,空间群P,晶胞参数a=1.4725(6),b=1.6480(7),c=2.1006(8)nm,a=83.928(7)?b=85.938(7)?g=85.212(7)?V=5.041(3)nm3,Dc=1.476g/cm3,Z=2,m=0.568nm-1,F(000)=2324,R=0.0778,wR=0.1821.标题化合物为四核钙配位化合物,4个Ca(Ⅱ)被4个配体5-羟基氧负离子-7-羟基黄酮-6-磺酸根的羰基和羟基氧负离子桥联,形成近似正方形.Ca(Ⅱ)的配位数都是7,配位原子分别来自5-羟基氧负离子-7-羟基黄酮-6-磺酸根的羟基、羰基、磺酸根的氧原子,以及水和DMSO的氧原子.4个配体位于4个配位Ca(Ⅱ)组成的正方形平面两侧,同侧配体两两平行且它们之间存在p-p堆积作用,异侧配体之间近似垂直.同时,发现了标题化合物固体具有光致发光现象,在lex=410nm条件下可发出lem=520nm的绿色荧光,并对其发光机制进行了探讨.  相似文献   

7.
刘飞  贺佑丰  罗志福 《化学学报》2002,60(9):1716-1721
合成了未见文献报道的[ReO(MPMEP)(BMPBA)][ReO(MPMEP)(BMPBA)]配合物,其 中MPMEP = 1-(2-甲氧基苯基)-4-(2-巯基乙基)哌嗪,BMPBA = N,N-二(2-巯 基乙基)苄胺,并在适当的溶剂中培养出单晶,用X射线单晶衍射法测定了单晶结 构,晶体属三斜晶系,空间群P1,晶胞参数a = 0.93604(19) nm,b = 1.1044(2) nm,c = 1.3823(3) nm;α = 89.19(3)°,β = 74.50(3)°,γ = 75.04(3)° ;Z = 1,V = 1.3281(5) nm~3,μ = 4.836 mm~(-1),F(000) = 677,R = 0. 0403,wR = 0.0673。配合物的两个[ReO(MPMEP)(BMPBA)]部分均采取扭曲的三角双 锥几何结构,基底面由三齿配体的两个硫原子与氧原子构成,三齿配体的一个氮原 子和单齿配体的一个硫原子分别占取两个顶角位置,硫原子的离子化致使配合物呈 电中性。  相似文献   

8.
Quantum mechanical analysis reveals that carbonyl reduction of aldehydes and ketones by the imine-based reductant cis-[Os(III)(tpy)(Cl)(NH═CHCH(3))(NSAr)] (2), which is accessible by reduction of the analogous nitrile, occurs by hydride-proton transfer (HPT) involving both the imine and sulfilimido ligands. In carbonyl reduction, water or alcohol is necessary to significantly lower the barrier for proton shuttling between ligands. The -N(H)SAr group activates the carbonyl group through hydrogen bonding while the -NC(H)CH(3) ligand delivers the hydride.  相似文献   

9.
Journal of Structural Chemistry - Porous framework coordination polymer (enH)(enH2)[{Cu2(μ-CN)}Re6S8(CN)6] (1) is obtained by a reaction of Cs2.67K1.33[Re6S8(CN)2(OH)4]·4H2O, CuCN, and...  相似文献   

10.
本文研究了在1:1丙酮-水混合溶剂中回流条件下, cis-[Pt(diphos)Cl2]与NaCNS之间的取代反应, 第一次合成了CNS的混合键合异构体的depe铂配合物cis-[Pt(depe)(NCS)(SCN)], 进行了分子结构测定, 属单斜晶系, 空间群为P21/n晶胞参数: a=7.296(5), b=14.434(4), c=18.042(4)A, β=95.72(8)°,V=1890.7A^, Z=4, Rf=0.0564, 在相同条件下用dPr'pe作了对照实验, 得到的是cis-[Pt(dPr'pe)(NCS)2], 属单斜晶系, 空间群为Cc, 晶胞参数, a=12.279(6),b=9.330(8), c=20.102(7)A, β=108.90(9), V=2179.0(3)A^3, Z=4,Rf=0.0419. 此外, 还从双膦烷基的空间效应和电子效应讨论了对取代反应产物的影响。  相似文献   

11.
12.
本文研究了在1:1丙酮-水混合溶剂中回流条件下, cis-[Pt(diphos)Cl2]与NaCNS之间的取代反应, 第一次合成了CNS的混合键合异构体的depe铂配合物cis-[Pt(depe)(NCS)(SCN)], 进行了分子结构测定, 属单斜晶系, 空间群为P21/n晶胞参数: a=7.296(5), b=14.434(4), c=18.042(4)A, β=95.72(8)°,V=1890.7A^, Z=4, Rf=0.0564, 在相同条件下用dPr'pe作了对照实验, 得到的是cis-[Pt(dPr'pe)(NCS)2], 属单斜晶系, 空间群为Cc, 晶胞参数, a=12.279(6),b=9.330(8), c=20.102(7)A, β=108.90(9), V=2179.0(3)A^3, Z=4,Rf=0.0419. 此外, 还从双膦烷基的空间效应和电子效应讨论了对取代反应产物的影响。  相似文献   

13.
The self-assembly of [Cu(II)(dien)(H(2)O)(2)](2+) and [W(V)(CN)(8)](3-) in aqueous solution leads to the formation (H(3)O){[Cu(II)(dien)](4)[W(V)(CN)(8)]}[W(V)(CN)(8)](2)·6.5H(2)O (1). The crystal structure of 1 consists of an unprecedented {[Cu(II)(dien)](4)[W(V)(CN)(8)]}(5+)(∞) chain of (2,8) topology, nonbridging [W(CN)(8)](3-) anions, and crystallization water molecules. The analysis of magnetic behavior of 1 was performed by the density functional theory (DFT) method and magnetic susceptibility measurements. The DFT broken symmetry approach gave two J(CuW) coupling constants: J(ax) = +2.9 cm(-1) assigned to long and strongly bent W-CN-Cu linkage, and the J(eq) = +1.5 cm(-1) assigned to short and less bent W-CN-Cu linkage, located at the axial and the equatorial positions of square pyramidal Cu(II) centers, respectively, in the hexanuclear {W(2)Cu(4)} chain subunit. The dominance of weak-to-moderate ferromagnetic coupling within the chain was confirmed by magnetic calculations. Zero-field susceptibility of the full chain segment {WCu(4)}(n) was calculated by a semiclassical analytical approach assuming that only one W(V) out of five ? spins of the chain unit WCu(4) is treated as a classical commuting variable. The calculation of the field dependence of the magnetization was performed separately by replacing the same spin with the Ising variable and applying the standard transfer matrix technique. The intermolecular coupling between the chain segments and off-chain [W(CN)(8)](3-) entities was resolved using the mean-field approximation set to be of antiferromagnetic character. The magnetic coupling parameters are compared with those of other low dimensional {Cu(II)-[M(V)(CN)(8)]} systems.  相似文献   

14.
A new complex [Cu(H2tea)(H2O)(imi)][Cu(H3tea)(imi)][Na{Mo8O26}] · 4H2O (H3tea =triethanolamine, imi = imidazole) has been synthesized in aqueous solution and characterized by elemental analysis, IR spectroscopy, thermal gravimetric analysis, and single-crystal X-ray diffraction. X-ray diffraction reveals that β-[Mo8O26]4? polyanions are linked by sodium ions to form a chain. The coppers are five- and six-coordinate for [Cu(H3tea)(imi)]2+ and [Cu(H2O)(H2tea)(imi)]+, respectively. Crystal packing is due to hydrogen bonds and π ··· π stacking interactions, giving a 3-D polymeric network. The magnetic properties of the title compound are also presented.  相似文献   

15.
本文研究了在1∶1丙酮-水混合溶剂中,回流条件下,cis-[Pt(diphos)Cl_2]与NaCNS之间的取代反应,第一次合成了CNS-的混合键合异构体的depe铂配合物cis-[Pt(depe)(NCS)(SCN)],进行了分子结构测定,属单斜晶系,空间群为P2_(1/n),晶胞参数:a=7.296(5),b=14.434(4),c=18.042(4) ,β=95.72(8)°,V=1890.7 ~3,Z=4,R_F=0.0564.在相同条件下用dPr~ipe作了对照实验,得到的是cis-[Pt(dPr~ipe)(NCS)_2],属单斜晶系,空间群为Cc,晶胞参数:a=12.279(6),b=9.330(8),c=20.102(7) ,β=108.90(9)°,V=2179.0(3) ~3,Z=4,R_F=0.0419。此外,还从双膦烷基的空间效应和电子效应讨论了对取代反应产物的影响。  相似文献   

16.
在中温混合溶剂热条件下合成了两个金属铜配位聚合物Cu3(2,2′-bipy)2(C8H4O4)2(C8H5O4)2和Cu(Ⅰ)Cu(Ⅱ)(4,4′-bipy)1.5(C8H4O4)(C8H5O4)(bipy=联吡啶,C8H4O4=1,3-间苯二甲酸),并对其进行了单晶结构解析及相关性能表征.配合物Cu3(2,2′-bipy)2(C8H4O4)2(C8H5O4)2(1)晶体属三斜晶系,P1空间群,a=1.03314(4)nm,b=1.08350(3)nm,c=1.15826(4)nm,α=83.104(2)°,β=84.609(2)°,γ=66.125(2)°,Z=1.配合物Cu(Ⅰ)Cu(Ⅱ)(4,4′-bipy)1.5(C8H4O4)(C8H5O4)(2)晶体属三斜晶系,P1空间群,a=1.06979(3)nm,b=1.09209(3)nm,c=1.47887(3)nm,α=91.795(2)°,β=93.2460(10)°,γ=118.6170(10)°,Z=2.通过使用不同的有机碱配体(2,2′-联吡啶和4,4′-联吡啶),并调节不同有机碱配体的用量,得到了结构不同的两个目标晶体产物相.产物均可稳定到3...  相似文献   

17.
18.

In absolute ethanol and in the presence of triethylorthoformate, reactions of metal(II) nitrates with linear tridentate amines afforded metal complexes of the formula M(NNN)(NO3)2, where M = Ni2+, Cu2+ and Zn2+, and NNN = dien and Medpt. The compounds fall into three categories in accordance with their stereochemistry and mode of binding of the nitrato ligands. Compounds I, [Ni(dien)(O2NO)(ONO2)] and III, [Zn(dien)(O2NO)(ONO2)] are isomorphous and isostructural. They crystallize in the monoclinic space group P21/n with nearly identical cell constants. The stereochemistry of these two compounds is such that the terdentate dien ligand forms a fac MN3 moiety with the two oxygens of the bidentate nitrato ligand trans to the terminal NH2. These ligands form the base of the octahedral arrangement in which the sixth position, trans to the secondary nitrogen of the dien, is an oxygen of the monodentate nitrato ligand. Compound IV, [Ni(Medpt)(O2NO)(ONO2)] falls into the same category as I and III despite the fact that the two rings in the Ni-Medpt moiety are six-membered rings, unlike those in compounds I and III which are five-membered rings. Nevertheless, the nickel-amine arrangement is fac. The bidentate nitrato-oxygens are trans to the terminal NH2 of the amine ligand, and the oxygen of the monodentate nitrato ligand is trans to the tertiary amine-nitrogen. Such stereochemistry is prevalent for nickel and zinc compounds. Interestingly, compound IV crystallizes as a conglomerate (space group P212121). Compound II, {[Cu(dien)(μ-ONO2)]NO3} belongs to the second category and has a polymeric structure. The repeating fragment in the polymeric chain is a Cu(dien)-O fragment with the monodentate nitrato ligand occupying an equatorial position of the base. A second oxygen of the equatorial nitrate becomes an axial ligand for an adjacent Cu-N3O fragment. In this way the substance propagates into an infinite chain. The repeating unit has an effective square pyramidal, five-coordinate, configuration. Finally, the compound crystallizes as a racemate. The second nitrate necessary for charge compensation of this copper(II) compound is ionic and its function is to hold the infinite chains of the lattice. The third category represented by compound V, [Cu(Medpt)(ONO2)2] contains two molecules in the asymmetric unit of the racemic lattice (monoclinic, space group P21/a). The structure of Cu-Medpt is unlike that of IV in that both species present in the asymmetric unit have the amine ligand in a mer configuration which together with a monodentate oxygen of a nitrato ligand form a base plane of a square pyramid. The fifth ligand of both Cu2+ ions is a second monodentate nitrato ligand. The stereochemical differences between the two Cu2+ ions are insignificant for the Cu-Medpt fragment, which share the same conformation and configuration. The major difference between the two species is the torsional angles defined by the Cu-O-N-O angles. The difference arises from variation in the hydrogens of the primary amine moieties selected by nitrato-oxygens to form intramolecular hydrogen bonds. Finally, there is a little variation in the equatorial Cu-ONO2 stereochemistry because of steric hindrance, imposed by the Medpt, preventing large torsional angles by these nitrato ligands. This is evident by comparing the two copper species shown in Finally, nitrate-to-Br ligand exchange was found to take place when KBr pellets are prepared for IR spectral measurements.  相似文献   

19.
高氯酸诺氟沙星铜(Ⅱ)(英)   总被引:3,自引:0,他引:3  
0CommentExtensiveinvestigationshavebeendoneaboutthesupramolecularchemistryofmetalionswithNor-floxacin(H-Norf,1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxylicacid)sincemanyorganiccompoundsusedinmedicinedonothaveapurelyorganicmodeofaction;someareacti-vatedorbiotransformedbymetalions,othershavedi-rectorindirecteffectonthemetalionmetabolism[1~5].ThereactionofCu(ClO4)2·6H2OwithH-Norfunderhydrothermalconditionsgivesamonomericcomplex[Cu(H-Norf)2](ClO4)2(1)inwhichCu髤i…  相似文献   

20.
《Polyhedron》1999,18(6):811-815
Oxidative addition of H–R (H--Ph and H2) to trans-Ir(--Ph)(CO)(PPh3)2 (2) gives the initial products, cis, cis-Ir(H)(--Ph)2(CO)(PPh3)2 (3a) and cis, cis-Ir(H)2(--Ph)(CO)(PPh3)2 (3b), respectively. Both cis-bis(PPh3) complexes, 3a and 3b undergo isomerization to give the trans-bis(PPh3) complexes, trans, trans-Ir(H)(--Ph)2(CO)(PPh3)2 (4a) and cis, trans-Ir(H)2(--Ph)(CO)(PPh3)2 (4b). The isomerization, 3b4b is first order with respect to 3b with k1=6.37×10−4 s−1 at 25°C under N2 in CDCl3. The reaction rate (k1) seems independent of the concentration of H2. A large negative entropy of activation (ΔS=−24.9±5.7 cal deg−1 mol−1) and a relatively small enthalpy of activation (ΔH=14.5±3.3 kcal mol−1) were obtained in the temperature range 15∼35°C for the isomerization, 3b4b under 1 atm of H2.  相似文献   

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