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1.
The [Cr(NCS)(edtrp)], [Cr(NCS)(R-pdtrp)] and [Cr(NCS)(S-pdtra)] complexes, that are derivatives of the trans-equatorial isomers of [Cr(edtrp)(H2O)]° and [Cr(R-pdtrp)(H2O)]° and the cis-equatorial isomer of [Cr(S-pdtra)-(H2O)]° (edtrp = ethylenediamine-N,N,N′-tripropionate, R-pdtrp = R-propane-1,2-diamine-N,N,N′-tripropionate, S-pdtra = S-propane-1,2-diamine-N,N,N′-triacetate) undergo aquation in alkaline media with a strong dependence of the rate on [OH] for the trans-equatorial isomers and a very weak dependence for the cis-equatorial isomer. The thiocyanate ligand release follows a stereoretentive course for all reactants. Based on kinetic data the reaction mechanism has been discussed. Rate differences between the isomers are interpreted in terms of an interchange via a conjugate base (I c.b.) mechanism, assuming an equilibrium between the cis-equatorial-CrIII-S-pdtra complexes with penta- and tetradentate coordination of the edta-like ligand. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

2.
3.
Summary The reaction between the title compound, ,,,-tetra(p-sulphonatophenyl)porphynatoaquacarbonylruthenate(II), [Ru(TPPS)(CO)(H2O)]4–, and CN- revealed that only the aqua ligand is substituted even in the presence of a large excess of the nucleophile. The pK a1 was spectrophotometrically determined as 13.4(5) (at 33.2 °C) and kinetically as 13.44(5) (at 33.6 °C). The rate of aqua substitution was determined as 89(4)m –1 s –1 at 35.1 °C and the activation enthalpy and entropy as 55.44(1) kJ mol–1 and-27.90(4) J K–1 mol–1, respectively.  相似文献   

4.
Two new complex anions, [Cr(N3)(S-pdtra)]– and [Cr(N3)(edtrp)]–, were obtained in solution by N3–/HN3 anation of the aqua analogues (S-pdtra = S-propane-1,2-diamine-N,N,N-triacetate, edtrp = ethylenediamine-N,N,N-tripropionate). Aquation of these species in acidic media leads to the same geometrical isomers as those used for the synthesis. The aquation rate is strongly dependent upon [H] and is substantially higher in D2O than in H2O. Protonation of the coordinated azide was not observed spectrophotometrically. The rate law and activation parameters have been determined and discussed.  相似文献   

5.
Single crystals of Ba2[(UO2)(C2O4)2(NCS)]NCS · 7H2O were prepared and studied by X-ray diffraction. The crystals are monoclinic, space group P21/c, Z = 4, a = 13.508(5) Å, b = 12.268(4) Å, c = 14.965(5) Å, β = 115.38(1)°, V = 2240.6(13) Å3. The main structural units in the crystal are the island complex species [(UO2)(C2O4)2(NCS)]3? corresponding to the crystal chemical group AB 2 01 M1 (A = UO 2 2+ , B01 = C2O 4 2? , M1 = NCS?) of uranyl complexes, which are united into a three-dimensional framework through electrostatic interactions and through hydrogen bonds involving oxalate and isocyanate ions and water molecules.  相似文献   

6.
The reaction of 4,4′-diaminodiphenylmethane (dadm), malonic acid (H2mal) and Cu(NO3)2 in aqueous solution results in a discrete binuclear Cu(II) macrocycle: [Cu(dadm)(mal)- (H2O)]2(2H2O. It crystallizes in monoclinic, space group P21/c with a = 15.231(3), b = 11.847(2), c = 9.801(2)A,Z= 106.75(3)o, V = 1693.5(6)A3, Z = 2, C32H40Cu2N4O12, Mr = 799.76, Dc = 1.568 g/cm3, λ(MoK() = 0.71073A, μ = 1.325 mm-1, F(000) = 828, the final R = 0.0531 and Wr = 0.1244 for 3421 observed reflections with I > 2σ(I). Each Cu(II) is coordinated by two oxygen atoms from a mal ligand, two nitrogen atoms from two dadm ligands and a water oxygen atom to form a triangle bipyramidal motif. The title compound possesses a distorted macrocycle enclosed by dadm with approximate dimensions of 8.3A× 5.9A.  相似文献   

7.
Cs3[UO2(CH3COO)3]2[UO2(CH3COO)(NCS)2(H2O)] (I) and Cs5[UO2(CH3COO)3]3[UO2 (NCS)4(H2O)] · 2H2O (II) have been synthesized via the reaction between uranyl acetate and cesium thiocyanate in aqueous solution. According to single-crystal X-ray diffraction data, both compounds crystallize in monoclinic system with the unit cell parameters a = 18.7036(5) Å, b = 16.7787(3) Å, c = 12.9636(3) Å, β = 92.532(1)°, space group C2/c, Z = 4, R = 0.0434 (I); and a = 21.7843(3) Å, b = 24.6436(5) Å, c = 13.1942(2) Å, β = 126.482(1)°, space group Cc, Z = 4, R = 0.0273 (II). Uranium-containing structural units of compound (I) are mononuclear [UO2(CH3COO)3]? and [UO2(CH3COO)(NCS)2(H2O)]? moieties, which correspond to the AB 3 01 and AB01M 3 1 crystallochemical groups (A = UO 2 2+ , B01 = CH3COO?, M1 = NCS? and H2O). The structure of compound II is built of [UO2(CH3COO)3]? and [UO2(NCS)4(H2O)]2? complexes, which belong to the AB 3 01 and AM 5 1 crystallochemical groups, respectively. Uranium-containing complexes in both structures are linked into a framework by hydrogen bonds and electrostatic interactions with cesium cations. The IR spectra of compounds I and II agree well with X-ray diffraction data.  相似文献   

8.
A single-crystal X-ray diffraction study (NH4)(CN3H6)2[(UO2(C2O4)2(NCS)] · 2H2O (I) was carried out. The crystals are orthorhombic, space group P212121, Z = 4, with the unit cell parameters a = 6.668(2) Å, b = 13.463(4) Å, c = 23.086(6) Å. The main structural units of the crystals of I are insular complex anions [(UO2)(C2O4)2(NCS)]3?. They belong to the crystal-chemical group AB 2 01 M1 (A = UO 2 2+ ) of uranyl complexes and are linked into a three-dimensional framework through electrostatic interactions and hydrogen bonds with the participation of ammonium and guanidinium cations and crystal water molecules.  相似文献   

9.
The title complexes, K3[Cd(Dtpa)] (H5Dtpa = diethylenetriamine-N,N,N,N′,N′-pentaacetic acid, (I)), K2[Cd(H2O)4][Cd(Edta)(H2O)]2 · 2H2O (H4Edta = ethylenediamine-N,N,N′,N′-tetraacetic acid, (II)), and Na2[Cd(H2O)4][Cd(Edta)(H2O)]2 · 2H2O (III), were prepared, and their compositions and structures were determined by elemental analyses, IR spectra, and single-crystal X-ray diffraction techniques, respectively. In complex I, the Cd is seven-coordinated by one Dtpa ligand yielding a pseudo-monocapped trigonal prism conformation, and the complex crystallizes in the triclinic crystal system with the Pi space group. The crystal data are as follows: a = 8.7300(17), b = 9.1200(18), c = 15.110(3) Å, α = 95.52(3)°, β = 96.59(3)°, γ = 99.63(3)°, V = 1170.0(4) Å3, Z = 2, ρ = 1.754 g/cm3, μ = 1.519 mm?1, F(000) = 616, R = 0.0644 and wR = 0.1712 for 3842 observed reflections with I ≥ 2σ(I). For complex II, in the [Cd(Edta)(H2O)]2? complex anion the Cd2+ ion is seven-coordinated by one Edta ligand and one water molecule, yielding a pseudo-pentagonal bipyramid conformation. In the [Cd(H2O)4]2+ cation, the bridged Cd is six-coordinated, yielding an almost standard octahedral conformation. The complex crystallizes in the monoclinic system with P21/n space group. The crystal data are as follows: a = 9.098(3), b = 16.442(6), c = 12.023(4) Å, β = 91.053(6)°, V = 1798.3(12) Å3, Z = 2, ρ = 2.098 g/cm3, μ = 2.086 mm?1, F(000) =1124, R = 0.0406 and wR = 0.1152 for 3680 observed reflections with I ≥ 2σ(I). In complex III, the conformations of Cd2+ ions are similar to those of the potassium salt complex, and the complex also crystallizes in the monoclinic crystal system with the P21/n space group. The crystal data are as follows: a = 9.134(7), b = 16.500(13), c = 12.075(10) Å, β = 91.054(12)°, V = 1820(2) Å3, Z = 2, ρ = 2.015 g/cm3, μ = 1.856 mm?1, F(000) = 1092, R = 0.0363 and wR = 0.0879 for 3707 observed reflections with I ≥ 2σ(I).  相似文献   

10.
11.
A novel two-dimensional supramolecular complex [Mn(phen)(DPZDA)(H2O)]·2H2Ohas been synthesized by the reaction of Mn(CH3COO)2, 1,10-phenanthroline (phen) and H2DPZDA (3,5-dimethyl-pyrazine-2,6-dicarboxylic acid). Elemental analysis, IR spectra and X-ray singlecrystal diffraction were carried out to determine the composition and crystal structure of the title complex. Crystal data: triclinic system, space group P-1, a = 7.7474(13), b = 9.3381(15), c =15.146(3)(A), α = 93.872(3), β = 102.451(11), γ = 105.261(11)°, C20H20MnN4O7, Mr = 483.34, Z = 2,F(000) = 498, V = 1023.2(3)(A)3, Dc = 1.569 g/cm3, μ = 0.697 mm-1, -9≤h≤9, -11 ≤k≤ 10, -18≤l≤12, R = 0.0365 and wR = 0.0901 for 3585 independent reflections (Rint = 0.0165) and 2923observed reflections (I > 2σ(I)). Structural analysis indicates that Mn(Ⅱ) adopts a distorted octahedral geometry. The 2-D framework supramolecular structure of the title complex is constructed from hydrogen bonds and π…πinteractions.  相似文献   

12.
HU Jiu-Rong  LIANG Fu-Pei   《结构化学》2007,26(7):793-796
A novel complex [Zn(FcCOO)2(2,2′-bipy)(H2O)]2·H2O (Fc = (η5-C5H5)Fe(η5-C5H4), 2,2′-bipy = 2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR and X-ray diffraction. It crystallizes in monoclinic system, space group P21/c with a = 6.8187(4), b = 21.7155(13), c = 19.7411(12) (A), α = 90, β = 97.7420(10), γ = 90°, C64H58Fe4Zn2N4O11, Mr = 1413.28, V = 2896.4(3) (A)3, Dc = 1.620 g/cm3, Z = 2, F(000) = 1444, μ(MoKα) = 1.857 mm-1, R = 0.0523 and wR = 0.0982 for 3219 observed reflections (I > 2σ(I)). Structural analysis shows that the zinc atom is coordinated with three oxygen atoms from two ferrocenemonocarboxylates and one water molecule together with two nitrogen atoms from 2,2′-bipyridine, giving a distorted square-pyramidal coordination geometry. The complex molecules are linked to form an infinite one-dimensional chain by both intermolecular hydrogen bonds and π-π stacking interactions of the bipyridine rings.  相似文献   

13.
A novel complex [Zn(FcCOO)2(2,2′-bipy)(H2O)]2·H2O (Fc = (η5-C5H5)Fe(η5-C5H4), 2,2′-bipy = 2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR and X-ray diffraction. It crystallizes in monoclinic system, space group P21/c with a = 6.8187(4), b = 21.7155(13), c = 19.7411(12) (A), α = 90, β = 97.7420(10), γ = 90°, C64H58Fe4Zn2N4O11, Mr = 1413.28, V = 2896.4(3) (A)3, Dc = 1.620 g/cm3, Z = 2, F(000) = 1444, μ(MoKα) = 1.857 mm-1, R = 0.0523 and wR = 0.0982 for 3219 observed reflections (I > 2σ(I)). Structural analysis shows that the zinc atom is coordinated with three oxygen atoms from two ferrocenemonocarboxylates and one water molecule together with two nitrogen atoms from 2,2′-bipyridine, giving a distorted square-pyramidal coordination geometry. The complex molecules are linked to form an infinite one-dimensional chain by both intermolecular hydrogen bonds and π-π stacking interactions of the bipyridine rings.  相似文献   

14.
Crystals of Ca[CoII(Nta)]2· 6H2O (I), where Nta3–is a nitrilotriacetate ion, were synthesized and studied using X-ray diffraction analysis. They were found to be monoclinic: a= 6.991(1), b= 10.031(1), c= 16.238(3) Å, = 98.50(1)°, V= 1126.2(3) Å3, space group P21/n, Z= 2, R 1= 0.0241, wR 2= 0.0636, GOOF = 1.050 (for 3132 reflections with I> 2(I)). Structure Iis composed of {[Co(Nta)(H2O)]}1anion chains united by Ca2+cations into a three-dimensional framework. The coordination polyhedra of Co and Ca atoms are distorted octahedra. The Co(II) atom environment includes atoms N(1), O(1), O(3), and O(5) of one Nta3–ligand, a carbonyl O(2)" atom of the neighboring anion fragment, and an O(w1) atom of the water molecule. The shortest bond is formed by the Co atom with the bridging O(2)" atom in trans-position relative to atom N(1). The Co–O(2)" distance (2.029 Å) is noticeably shorter than the other bond lengths, Co–O(Nta) (2.069–2.103 Å), Co–O(w1), and Co–N(1) (2.155 and 2.177 Å, respectively). Cations Ca2+are located in the inversion centers and involve in their coordination atoms O(4), O(6), O(w2), and the oxygen atoms symmetrically bond to them and arranged at 2.271(1), 2.420(1), and 2.351(2) Å, respectively. The structural formula of the title compound is {Ca(H2O)2[Co(Nta)(H2O)]2}3· 2H2O.  相似文献   

15.
Three complexes, Na4[DyIII(dtpa)(H2O)]2?·?16H2O, Na[DyIII(edta)(H2O)3]?·?3.25H2O and Na3[DyIII (nta)2(H2O)]?·?5.5H2O, have been synthesized in aqueous solution and characterized by FT–IR, elemental analyses, TG–DTA and single-crystal X-ray diffraction. Na4[DyIII(dtpa)(H2O)]2?·?16H2O crystallizes in the monoclinic system with P21/n space group, a?=?18.158(10)?Å, b?=?14.968(9)?Å, c?=?20.769(12)?Å, β?=?108.552(9)°, V?=?5351(5)?Å3, Z?=?4, M?=?1517.87?g?mol?1, D c?=?1.879?g?cm?3, μ?=?2.914?mm?1, F(000)?=?3032, and its structure is refined to R 1(F)?=?0.0500 for 9384 observed reflections [I?>?2σ(I)]. Na[DyIII(edta)(H2O)3]?·?3.25H2O crystallizes in the orthorhombic system with Fdd2 space group, a?=?19.338(7)?Å, b?=?35.378(13)?Å, c?=?12.137(5)?Å, β?=?90°, V?=?8303(5)?Å3, Z?=?16, M?=?586.31?g?mol?1, D c?=?1.876?g?cm?3, μ?=?3.690?mm?1, F(000)?=?4632, and its structure is refined to R 1(F)?=?0.0307 for 4027 observed reflections [I?>?2σ(I)]. Na3[DyIII(nta)2(H2O)]?·?5.5H2O crystallizes in the orthorhombic system with Pccn space group, a?=?15.964(12)?Å, b?=?19.665(15)?Å, c?=?14.552(11)?Å, β?=?90°, V?=?4568(6)?Å3, Z?=?8, M?=?724.81?g?mol?1, D c?=?2.102?g?cm?3, μ?=?3.422?mm?1, F(000)?=?2848, and its structure is refined to R 1(F)?=?0.0449 for 4033 observed reflections [I?>?2?σ(I)]. The coordination polyhedra are tricapped trigonal prism for Na4[DyIII(dtpa)(H2O)]2?·?16H2O and Na3[DyIII(nta)2(H2O)]?·?5.5H2O, but monocapped square antiprism for Na[DyIII(edta)(H2O)3]?·?3.25H2O. The crystal structures of these three complexes are completely different from one another. The three-dimensional geometries of three polymers are 3-D layer-shaped structure for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 1-D zigzag type structure for Na[DyIII(edta)(H2O)3]?·?3.25H2O and a 2-D parallelogram for Na3[DyIII(nta)2(H2O)]?·?5.5H2O. According to thermal analyses, the collapsing temperatures are 356°C for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 371°C for Na[DyIII(edta)(H2O)3]?·?3.25H2O and 387°C for Na3[DyIII(nta)2(H2O)]?·?5.5H2O, which indicates that their crystal structures are very stable.  相似文献   

16.
Na[YbIII(Cydta)(H2O)2] · 5H2O (1) (H4Cydta = trans-1,2-cyclohexanediamine-N,N,N′,N′-tetraacetic acid) and [YbIII(Hegta)] · 2H2O (2) (H4egta = ethyleneglycol-bis-(2-aminoethylether)-N,N,N′,N′-tetraacetic acid) were prepared and their composition and structures were determined by elemental analyses and single-crystal X-ray diffraction techniques. Complex 1 crystallized in the triclinic crystal system with space group P 1; the YbIII is eight-coordinate by a hexadentate Cydta and two water molecules. Complex 2 is a protonated egta complex, crystallized in the monoclinic crystal system with space group P 2 1 /c; YbIII is coordinated only by the octadentate Hegta ligand. Both these complexes adopt a pseudo-square antiprismatic conformation.  相似文献   

17.
Enthalpies of ligand substitution for [Mo(η5-C5H5)(CO)2(NO)] producing [Mo(η5-C5H5)Mo(CO)(L)(NO)] have been measured by solution calorimetry at 30 °C in THF for L = P(OMe)3 < PMePh2 < SIPr < PMe2Ph < IPr < PMe < PnBu3 (SIPr = 1,3-bis(2,6-bis(diisopropylphenyl)imidazolinylidene; IPr = 1,3-bis(2,6-bis(diisopropylphenyl)-imidazol-2-ylidene)). The accepting metal fragment [Mo(η5-C5H5)(CO)(NO)] has a vacant site containing strongly π-accepting carbonyl and nitrosyl ligands and this is shown to influence the stability of the product complex. Infrared studies of both νCO and νNO show that metal-to-ligand backbonding increases in the order P(OMe)3 < PMe3 < SIPr < IPr implying that both steric and electronic factors play a role in determining complex stability. The crystal structures of [Mo(η5-C5H5)(CO)(IPr)(NO)] and [Mo(η5-C5H5)(CO)(SIPr)(NO)] are reported.  相似文献   

18.
A new copper compound constructed from H2 Pmal (phenylmalonic acid), Dadm (4,4-diaminodiphenylmethane) and Cu(Ⅱ) has been synthesized from H2O-EtOH-DMF solution, and is characterized by X-ray single-crystal diffraction and other measurements. The compound crystallizes in the monoclinic system, space group C2/c with a=13.7866(6), b=10.1557(4), c=30.9036(17), β=101.422(5)o, V=4241.2(3)3 , Z=4, Dc=1.547g/cm3 , Mr=987.94, F(000)=2056, μ(MoKα)=1.078 mm-1 , S=1.007, R=0.0453 and wR=0.987 for 2806 observed reflections (I>2σ (I)). The title compound is characteristic of the cyclic dimeric molecules which further aggregate through hydrogen bonds and π-π interactions to form a 3-D supramolecular network. The microbial activities of the title compound and its reagents are investigated with filter paper discs diffusion method. The results show that the activity of the title compound is slightly better than its precursor reagents.  相似文献   

19.
Two novel complexes, (EnH2)1.5[HoIII(Ttha)] · 4.5H2O (I) (En = ethylenediamine and H6Ttha = triethylenetetramine-N,N,N′,N″,N?,N?-hexaacetic acid) and (EnH2)[HoIII(Egta)(H2O)]2 · 6H2O (II) (H4Egta = ethyleneglycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid), were synthesized and their crystal structures were determined by single crystal X-ray diffraction techniques. Complex I has a nine-coordinate mononuclear structure with distorted tricapped trigonal prismatic conformation and crystallizes in the monoclinic crystal system with P2/n space group. The crystal data are as follows: a = 17.7541(18), b = 9.6810(10), c = 22.166(2) Å, β = 118.913(2)°, and V = 3335.0(6) Å3. Complex II has a mononuclear nine-coordinate structure with pseudo-monocapped square antiprismatic conformation and crystallizes in the monoclinic crystal system with P21/n space group. The crystal data are as follows: a = 12.978(8), b = 12.685(8), c = 14.905(9) Å, β = 105.333(7)°, and V = 2366(2) Å3. In I, there are two types of EnH 2 2+ anions. They connect to [HoIII(Ttha)]3? by hydrogen bonds leading to the formation of 3D pore structure along z axis. In II, EnH 2 2+ cation connects three adjacent [HoIII(Egta)(H2O)]? complex anions through hydrogen bonds, these hydrogen bonds lead to the formation of 2D network structure in [101] plane. The results showed that ligand structures play a crucial role in crystal and molecular structure of their complexes. In addition, the protonated (EnH 2 2+ ) cations conjugating to [HoIII(Ttha)]3? and [HoIII(Egta)(H2O)]? complex anions are reviewed, which act as an important beginning for study of Ho(III) complexes conjugating with other various amino and heterocyclic biomolecule.  相似文献   

20.
在pH为3的醇水混合溶剂中合成了β-丙氨酸、1,10-邻菲咯林、铜的三元配合物,测定了配合物的晶体结构.晶体属单斜晶系,Pī空间群,晶胞参数a=1.0045(2) nm, b=1.2132(2) nm, c=0.71682(14) nm, α= 93.88(3)°, β= 94.31(3)°, γ= 99.81(3)°, V=0.8555(3) nm3, Z=2, Dc=1.669 Mg·m-3, μ=1.326 mm-1, F(000)=442, R=0.0457, Rw=0.1179.配合物中铜离子的配位数为5,分子间通过氢键构成三维网状结构.  相似文献   

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