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1.
Connecting two discotic mesogens via a spacer not only stabilizes the columnar mesophase but also leads to the formation of glass columnar phase, and therefore improves the physical properties of discotic liquid crystals as organic semiconductor. Here, we report the synthesis of eight diacetylene-bridged triphenylene discotic liquid crystal dimers, [C18H6(OCnH2n+1)4(OMe)O2C-C8H16-C≡≡ C-]2, 3(n), (n = 4-8), [C18H6(OC6H13)5O2C-C8H16-C≡≡ C-]2, 6 and [C18H6(OC6H13)5O-(CH2)m-C≡≡ C-]2, 8(m), (m = 1, 3) by Eglinto... 相似文献
2.
Joanna Wiśniewska 《Transition Metal Chemistry》2007,32(6):811-815
The kinetics of the electron-transfer reactions between promazine (ptz) and [Co(en)2(H2O)2]3+ in CF3SO3H solution ([CoIII] = (2–6) × 10−3
m, [ptz] = 2.5 × 10−4
m, [H+] = 0.02 − 0.05 m, I = 0.1 m (H+, K+, CF3SO
3
−
), T = 288–308 K) and [Co(edta)]− in aqueous HCl ([CoIII] = (1 − 4) × 10−3
m, [ptz] = 1 × 10−4
m, [H+] = 0.1 − 0.5 m, I = 1.0 m (H+, Na+, Cl−), T = 313 − 333 K) were studied under the condition of excess CoIII using u.v.–vis. spectroscopy. The reactions produce a CoII species and a stable cationic radical. A linear dependence of the pseudo-first-order rate constant (k
obs) on [CoIII] with a non-zero intercept was established for both redox processes. The rate of reaction with the [Co(en)2(H2O)2]3+ ion was found to be independent of [H+]. In the case of the [Co(edta)]− ion, the k
obs dependence on [H+] was linear and the increasing [H+] accelerates the rate of the outer-sphere electron-transfer reaction. The activation parameters were calculated as follows:
ΔH
≠ = 105 ± 4 kJ mol−1, ΔS
≠ = 93 ± 11 J K−1mol−1 for [Co(en)2(H2O)2]3+; ΔH
≠ = 67 ± 9 kJ mol−1, ΔS
≠ = − 54 ± 28 J K−1mol−1 for [Co(edta)]−. 相似文献
3.
D. A. Kissounko M. V. Zabalov Yu. F. Oprunenko D. A. Lemenovskii 《Russian Chemical Bulletin》2000,49(7):1282-1286
Reactions of 2-ethyl-5-methylcyclopenta[b]thienyllithium (thiopentalenyllithium) (2) with various electrophilic reagents afford σ-element-substituted thiopentalenes. However, the reaction with Ph3SnCl yields only one of two possible isomers,viz, triphenyl(4H-cyclopenta[b] thiophen-4-yl)stannane (4c), whereas the reactions with Me3SiCl, Me3SiCl, or Ph2PCl give both possible isomers,viz., trimethyl(6H-cyclopenta[b]thiophen-6-yl)silane (3a) and trimethyl(4H-cyclopental[b]thiophen-4-yl)silane (4a), trimethyl(6H-cyclopenta[b]thiophen-6-yl)stannane (3b) and trimethyl(4H-cyclopental[b]thiophen-4-yl)stannane (4b), or diphenyl(6H-cyclopenta[b]thiophen-6-yl)phosphine (3d) and diphenyl(4H-cyclopenta[b]thiophen-4-yl)phosphine (4d) in ratios of 1∶2, 1∶2, or 1∶1, respectively. The structure of compound4c was established by X-ray diffraction analysis. The observed regioselectivity of formation of compound4c is attributed to the specific precoordination of the tin atom by the sulfur atom of the thiopentalenyl ligand and to the
steric overcrowding of the Sn atom in organotin electrophiles.
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1285–1289, July, 2000. 相似文献
4.
Triphenylmethyl salts of the very weakly-coordinating borate anions [CN{B(C6F5)3}2]− (1), [H2N{(C6F5)3}2]− and [M{CNB(C6F5)3}4]2− (M = Ni, Pd) have been prepared in simple one-pot reactions. Mixtures of (SBI)ZrMe2/1/AlBu
3
i
(SBI = rac-Me2Si(Ind)2) are 30–40 times more active in ethylene polymerizations at 60–100°C than (SBI)ZrCl2/MAO. The quantification of anion effects on propene polymerization activity at 20°C gives the order [CN{B(C6F5)3}2]− > [H2N{(C6F5)3}2]− ≈ B(C6F5)
4
−
≫ [MeB(C6F5)3]−. The highest productivities were of the order of ca. 3.0 × 108 g PP (mol Zr)−1 h−1 [C3H6]−1, about 1.3–1.5 times higher than with B(C6F5)
4
−
as the counter anion. The titanium system CGCTiMe2/1/AlBu
3
i
gave activities that were very similar to the zirconocene catalyst. The concentration of active species [C*] as determined
by quenched-flow kinetic techniques indicates typical values of around 10%, independent of the counter anion, for both the
borate and MAO systems. Pulsed field-gradient spin echo and nuclear Overhauser effect NMR experiments on systems designed
to be more realistic models for active species with longer polymeryl chains, (SBI)M(CH2SiMe3)(μ-Me)B(C6F5)3 and [(SBI)MCH2SiMe
3
+
...B(C6F5)
4
−
] (M = Zr, Hf), demonstrated the influence of bulky alkyl chains on the ion pair solution structures: while the MeB(C6F5)3 compound exists as a simple inner-sphere ion-pair, the B(C6F5)
4
−
compound is an outer-sphere ion pair (OSIP), a consequence of the relegation of the anion into the second coordination sphere
by the γ-agostic interaction with the alkyl ligand. The OSIP aggregates to ion hextuples (10 mM) or quadruples (2 mM). Implications
for the polymerization mechanism are discussed; the process follows an associative interchange (I
a) pathway.
The text was submitted by the authors in English. 相似文献
5.
Bhawana Gupta Nidhi Kalgotra Savit Andotra Sushil K. Pandey 《Monatshefte für Chemie / Chemical Monthly》2012,39(5):1087-1095
Abstract
O-Tolyl/benzyl dithiocarbonates, ROCS2Na (R = o-, m-, or p-CH3C6H4–, and –CH2C6H5), were synthesized and characterized. These new ligands reacted with PCl3/POCl3 in refluxing toluene which resulted in the formation of phosphorus(III) and phosphorus(V) tolyl/benzyl dithiocarbonates corresponding to [(ROCS2) n PCl3−n ] and [(ROCS2) n POCl3−n ] (R = o-, m-, or p-CH3C6H4–, and –CH2C6H5; n = 1, 2, 3). These pale yellow liquid compounds were characterized by IR, mass, and NMR (1H, 13C, and 31P) spectral studies, which suggest the dithiocarbonate ligands bind in a monodentate mode leading to P–S–C linkages in these derivatives. 相似文献6.
Eduard V. Ganin Vladimir O. Gelmboldt Larisa V. Koroeva Marina S. Fonari Yurii A. Simonov Janusz Lipkowski Sergei A. Kotlyar Gerbert L. Kamalov 《Journal of inclusion phenomena and macrocyclic chemistry》2006,56(3-4):345-354
The reaction of Nb2O5 and Ta2O5 with an aqueous solution of hydrofluoric acid, HF in the presence of biphenyl-20-crown-6 (BP20C6, L1) or [1.5]dibenzo-18-crown-6 ([1.5]DB18C6, L2) results in the complexes [L1·(H3O)][NbF6] (1), [L1 (H3O)][TaF6] (2), [2L2·(H7O3)][NbF6] (3) and [2L2·(H7O3)][TaF6] (4). Complexes 1–4 were identified by the elemental and X-ray structural analysis and IR spectroscopy. Complexes 1 and 2 are isostructural, with the H3O+ oxonium ion embedded in one crown molecule via OH···O hydrogen bonds. Complexes 3 and 4 represent the supramolecular isomers distinctive by the crown conformations and crystal packing, with the (H7O3)+ cation enclosed in the cage of two crown molecules. Being poor H-bond acceptors, NbF6− and TaF6− anions do not compete with the crown oxygen atoms for the oxonium hydrogen atoms, but are involved in the numerous C–H···F
short contacts responsible for the extended supramolecular architectures in all cases. A change of crown ethers’ conformation
in complexes 1–4 and a correlation between the degree of proton hydration and an accessibility of the crown ether oxygen atoms is observed.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
7.
M. S. Nechaev I. V. Borisova N. N. Zemlyanskii D. N. Laikov Yu. A. Ustynyuk 《Russian Chemical Bulletin》2000,49(11):1823-1830
The structures of 6,6-dimethyl-6-silafulvene C5H4SiMe2 (3), its donor-acceptor complex with ammonia. C5H4SiMe2·NH3, dimethylfulvene, a number of cyclopentadienylides, methylenetrimethylphosphorane (6), and silicon-containing organophosphorus betaine−C5H4SiMe2CH2PMe3
+ (13), the product of nucleophilic addition of6 to3, were calculated using the density functional approach. For compound13, the potential energy minimum corresponds to the conformation withgauche-arrangement of the cyclopentadienyl anionie and trimethylphosphonium cationic centers and a C−Si−C−P dihedral angle of 30.5°,
which is due to the Coulomb attraction between these centers. According to calculations, betaine13 is rather stable toward decomposition into3 and6 (ΔH
o=42 kcal mol−1, ΔG
Δ=30 kcal mol−1). The main channel of thermal decomposition of compound13 involves an intramolecular nucleophilic substitution, which proceeds with elimination of trimethylphosphine and results in
1,1-dimethyl-1-silaspiro[2,4]hepta-4,6-diene, which then undergoes a ready and irreversible isomerization into 6,6-dimethyl-6-silabicyclo[3.2.0]hepta-1,3-diene
owing to the [1.5]-sigmatropic shift of the C−Si bond.
For Part 4, see Ref. 1.
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1850–1857, November, 2000. 相似文献
8.
The desolvation process in lanthanide pyridine-3,5-dicarboxylates of the formulae [Tb2pdc3(dmf)2]·dmf (1), [Ho2pdc3(dmf)2]·dmf (2), [Erdc3(dmf)2]·dmf (3), and [Yb2pdc3(dmf)2]·dmf (4) where pdc-C5H3N(COO)22−, dmf-N,N′-dimethylformamide) has been investigated by means of the TG–DSC, TG–FTIR, IR and XRD methods. Heating of the complexes in
the range 30–260 °C lead to evolution of weakly bonded dmf molecules included in the channels as well those directly bonded
with lanthanide atoms. The kinetic analysis revealed a multistep desolvation pattern. 相似文献
9.
A. N. Chekhlov 《Russian Journal of Inorganic Chemistry》2008,53(9):1465-1469
Three new crystalline complexes are synthesized: [K(18-crown-6)]+ · An, where An = [FeCl4]?(I), [FeBr2Cl2]? (II), and [FeBr4]? (III). The crystals of compounds I–III are cubic and isomorphic, space group Fd $ \bar 3 Three new crystalline complexes are synthesized: [K(18-crown-6)]+ · An, where An = [FeCl4]−(I), [FeBr2Cl2]− (II), and [FeBr4]− (III). The crystals of compounds I–III are cubic and isomorphic, space group Fd
(Z = 16): a = 20.770(2) ? for I, 20.844(3) ? for II, and 20.878(4) ? for III. Structures I–III are solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.047 (I), 0.059 (II), and 0.098 (III) for all 680 (I), 684 (II), and 686 (III) independent reflections. In two tetrahedral anions [Fe(1)X4]− and [Fe(2)X4]− in structures I–III, all halogen atoms (X = Cl and Br) are randomly disordered over three close positions relative to the crystallographic axes
3. Structures I–III contain the [K(18-crown-6)]+ host-quest complex cation. The K+ cation (CN = 8) resides in the cavity of the 18-crown-6 ligand and coordinated by its six O atoms and two disordered halogen
X atoms. The coordination polyhedron of the K+ cation in complexes I–III is a distorted hexagonal bipyramid.
Original Russian Text ? A.N. Chekhlov, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 9, pp. 1566–1570. 相似文献
10.
D. A. Loginov A. A. Pronin L. S. Shul’pina E. V. Mutseneck Z. A. Starikova P. V. Petrovskii A. R. Kudinov 《Russian Chemical Bulletin》2008,57(3):546-551
The mononuclear arene complexes [Cb*Co(arene)]+ (3a–g; Cb* = C4Me4; arene is biphenyl (a), diphenylmethane (b), 1,2-diphenylethane (c), diphenyl ether (d), p-terphenyl (e), 1,2-dimesitylethane (f), or 1,3-dimesitylpropane (g)) were synthesized by the reactions of arenes either with the benzene complex [Cb*Co(C6H6)]+ (1) under visible light irradiation or with the acetonitrile derivative [Cb*Co(MeCN)3]+ (2) in refluxing THF. The reactions of 2 with 1,2-diphenyle-thane, 1,3-dimesitylpropane, and p-terphenyl in a ratio of 2: 1 afforded the dinuclear complexes [Cb*Co(μ-η:η-arene)CoCb*]2+ (4c,e,g). The stability of the dinuclear arene complexes was estimated by DFT calculations. The structures of the complexes [3a]PF6 and [3e]PF6 ere established by X-ray diffraction.
For Part 6, see Ref. 1.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 535–539, March, 2008. 相似文献
11.
Felipe Gómez-de la Torre Yolanda Gutiérrez Félix A. Jalón Blanca R. Manzano Ana Rodríguez 《Monatshefte für Chemie / Chemical Monthly》2000,131(12):1267-1280
Summary. Partial removal of chloride anions from the dimer [Pd(η3-2-CH3*C3H4)(μ-Cl)]2 with AgTf(Tf = CF3SO3) followed by addition of dppm affords [Pd2(η3-Me*C3H4)2(μ-Cl)(μ-dppm)]Tf (1). The substitution of Cl− by X− (X = pz, SC6F5, S
py
) using the appropriate salts yields the new derivatives [Pd2(η3-Me*C3H4)2(μ-X)(μ-dppm)]Tf (2–4). All complexes exhibit a dinuclear half-A-frame structure with two isomers present in solution. The isomers differ in the
relative orientation of the two allyl groups (cis or trans). The isomer interconversion was studied by variable temperature 1H NMR spectroscopy. The molecular structures of 2 and 4 were solved by X-ray diffraction studies. A distorted boat conformation of the seven- or six-membered metallacycle was found
in both cases.
Received June 7, 2000. Accepted June 20, 2000 相似文献
12.
W. Guan L. Li H. Wang J. Tong J. -Z. Yang 《Journal of Thermal Analysis and Calorimetry》2008,94(2):507-510
A brown and transparent ionic liquid (IL), [C4mim][FeCl4], was prepared by mixing anhydrous FeCl3 with 1-butyl-3-methylimidazolium chloride ([C4mim][Cl]), with molar ratio 1/1 under stirring in a glove box filled with dry argon. The molar enthalpies of solution, Δs
H
m, of [C4mim][FeCl4], in water with various molalities were determined by a solution-reaction isoperibol calorimeter at 298.15 K. Considering
the hydrolyzation of anion [FeCl4]− in dissolution process of the IL, a new method of determining the standard molar enthalpy of solution, Δs
H
m0, was put forward on the bases of Pitzer solution theory of mixed electrolytes. The values of Δs
H
m0 and the sum of Pitzer parameters: and were obtained, respectively. In terms of thermodynamic cycle and the lattice energy of IL calculated by Glasser’s lattice
energy theory of ILs, the dissociation enthalpy of anion [FeCl4]−, ΔH
dis≈5650 kJ mol−1, for the reaction: [FeCl4]−(g)→Fe3+(g)+4Cl−(g), was estimated. It is shown that large hydration enthalpies of ions have been compensated by large the dissociation enthalpy
of [FeCl4]− anion, Δd
H
m, in dissolution process of the IL. 相似文献
13.
Bikshandarkoil R. Srinivasan Christian Näther Sunder N. Dhuri Wolfgang Bensch 《Monatshefte für Chemie / Chemical Monthly》2006,137(4):397-411
Summary. Four new organic ammonium tetrathiotungstates (N–Me–enH2)[WS4] (1), (N,N′-dm-1,3-pnH2)[WS4] (2), (1,4-bnH2)[WS4] (3), and (mipaH)2[WS4] (4), (N–Me–enH2 = N-methylethylenediammonium, N,N′-dm-1,3-pnH2 = N,N′-dimethyl-1,3-propanediammonium, 1,4-bnH2 = 1,4-butanediammonium, and mipaH = monoisopropylammonium) were synthesized by the base promoted cation exchange reaction and characterized by elemental analysis,
infrared, Raman, UV-Vis and 1H NMR spectroscopy as well as single crystal X-ray crystallography. The structures of 1–4 consist of [WS4]2− tetrahedra which are linked to the organic ammonium cations via N–H⋯S hydrogen bonding. The strength and number of the S⋯H
interactions affect the W–S bond lengths as evidenced by distinct short and long W–S bonds. The IR spectra exhibit splitting
of the W–S vibrations, which can be attributed to the distortion of the [WS4]2− tetrahedron. From a comparative study of several known tetrathiotungstates it is observed that a difference of more than
0.033 ? between the longest and shortest W–S bonds in a tetrathiotungstate will result in the splitting of the asymmetric
stretching vibration of the W–S bond. 相似文献
14.
Bikshandarkoil R. Srinivasan Christian N?ther Sunder N. Dhuri Wolfgang Bensch 《Monatshefte für Chemie / Chemical Monthly》2006,121(2):397-411
Four new organic ammonium tetrathiotungstates (N–Me–enH2)[WS4] (1), (N,N′-dm-1,3-pnH2)[WS4] (2), (1,4-bnH2)[WS4] (3), and (mipaH)2[WS4] (4), (N–Me–enH2 = N-methylethylenediammonium, N,N′-dm-1,3-pnH2 = N,N′-dimethyl-1,3-propanediammonium, 1,4-bnH2 = 1,4-butanediammonium, and mipaH = monoisopropylammonium) were synthesized by the base promoted cation exchange reaction and characterized by elemental analysis,
infrared, Raman, UV-Vis and 1H NMR spectroscopy as well as single crystal X-ray crystallography. The structures of 1–4 consist of [WS4]2− tetrahedra which are linked to the organic ammonium cations via N–H⋯S hydrogen bonding. The strength and number of the S⋯H
interactions affect the W–S bond lengths as evidenced by distinct short and long W–S bonds. The IR spectra exhibit splitting
of the W–S vibrations, which can be attributed to the distortion of the [WS4]2− tetrahedron. From a comparative study of several known tetrathiotungstates it is observed that a difference of more than
0.033 ? between the longest and shortest W–S bonds in a tetrathiotungstate will result in the splitting of the asymmetric
stretching vibration of the W–S bond. 相似文献
15.
Ying Liu Shuxia Liu Hongmei Ji Shiwei Zhang Lili Cai Ruige Cao 《Journal of Cluster Science》2009,20(3):535-543
Abstract Two organic–inorganic hybrid compounds based on the Anderson-type clusters [TeMo6O24]6−, [(H2O)2Co(TeMo6O24)][(C10N2H10)2] · 9.5H2O (1), [(C10N2H9)Ni(H2O)3]2[TeMo6O24] · 8.5H2O (2), have been synthesized by hydrothermal reactions and characterized by elemental analyses, IR spectra, thermal stability analyses,
and single-crystal X-ray diffraction. Compound 1 displays a 1D chain structure constructed from alternating [TeMo6O24]6−clusters and Co2+ along the a axis with two pendant ligands 4,4′-bpy (4,4′-bipyridine). Compound 2 is composed of [TeMo6O24]6− clusters coordinated by [Ni(bpy)(H2O)3]2+ moieties, and a supramolecular architecture is further formed through extensive hydrogen bonds interactions.
Graphical Abstract Two organic–inorganic hybrid compounds based on the Anderson-type clusters [TeMo6O24]6−and the unit [M(4,4′-bpy)] have been synthesized under the hydrothermal conditions. Compound 1 displays a 1D chain structure constructed covalently from alternating polyoxoanions [TeMo6O24]6− and Co2+ along the a axis with two pendant ligands 4,4′-bipyridine. Compound 2 is composed of [TeMo6O24]6− polyoxoanion coordinated by [Ni(bpy)(H2O)3]2+ moieties and shows a 1D chain structure through the hydrogen bonds interactions.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
16.
O. Chiobenika P. Bourosh V. Lozan O. Bologa I. Bulkhak B. Wicher Yu. Simonov 《Russian Journal of Inorganic Chemistry》2011,56(7):1050-1059
New cobalt trans-dioximate complexes with isoniconinamide have been synthesized: [CoII(DmgH)2(Inia)2] (I), [CoIII(DmgH)2(Inia)2][PF6] · 1.5H2O (II), [CoIII(NioxH)2 (Inia)2][PF6] · H2O · CH3OH (III), and [CoIIICl(DmgH)2(Inia)] · H2O (IV), where DmgH− and NioxH− are the dimeth-ylglyoxime and 1,2-cyclohexanedionedioxime monoanions, respectively; Inia is the isonicotinamide molecule.
The structures of compounds I–IV have been determined by X-ray crystallography. In I–IV, Co(II) or Co(III) has an octahedral environment with the pseudomacrocyclic (DioxH−)2 moiety (DioxH− is the dioximate monoanion) in the equatorial plane. The latter is stabilized by O-H…O hydrogen bonds. The isonicotinamide
molecules in all four complexes are monodentately bound to the metal ion through the heterocyclic nitrogen atom. 相似文献
17.
New liquid-crystalline heteropolynuclear complexes L2M (M=Cu2+ (2a), Pd2+ (2b)) were synthesized by the reactions of C5H5FeC5H4−C6H4NH−C2H2−(CO)−C6H4OC12H25 (1, LH) with copper(ii) and palladium(ii) acetates. Compound2b was found to possess monotropic nematic and smectic phases;2a exhibits the monotropic nematic phase and a phenomenon of “double melting”. The compositions and structures of compounds1 and2a,b were established by elemental analysis,1H and13C NMR, ESR, and IR spectroscopy.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 381–383, February, 1999. 相似文献
18.
Kinetics and mechanism of bromide ions oxidation by cerium(IV) in sulphuric acid solutions revisited
Anna Katafias 《Transition Metal Chemistry》2006,31(7):907-911
Kinetics of Br− anion oxidation by cerium(IV) species in aqueous H2SO4 solutions have been reexamined. The rate of reaction was determined spectrophotometrically based on a factor analysis of
the absorbance – time data collected in the wavelength range 318–390 nm – the region characteristic for the cerium(IV) sulphato
complexes. The data fit very well to a pseudo-first order dependence under a large molar excess of the reductant. The rate
law of the form –d[CeIV]/dt = k[CeIV][Br–]2 has been obtained at constant H2SO4 concentration and ionic strength I = 2 m. The pseudo-first order rate constant decreases with an [H2SO4] increase from 0.1 to ca. 0.4 m range, then increases for higher [H2SO4]. The apparent activation parameters have been calculated from the third order rate constants k for different [H2SO4]. 相似文献
19.
Jiaoyun Xia Yongxian Wang Junfeng Yu Shiqiang Li Lin Tang Mingqiang Zheng Xiuqing Liu Gucai Li Dengfeng Cheng Sheng Liang Duanzhi Yin 《Journal of Radioanalytical and Nuclear Chemistry》2008,275(2):325-330
Radiolabeling of biologically active molecules with fac-[188Re(CO)3(H2O)3]+ unit has been of primary interest in recent years. Therefore, we herein report ligands L1−L4 (L1=histidine, L2=nitrilotriacetic acid, L3=2-picolylamine-N,N-diacetic acid, L4=bis(2-pyridymethy)amine) that have been evaluated by radiochemical reactions with fac-[188Re(CO)3(H2O)3]+. These reactions yielded the radioactive complexes of fac-[188Re(CO)3L] (L = L1−L4, 188Re tricarbonyl complexes 1–4), which were identified by HPLC. Complexes 1–4, with log P
o/w
values ranging from −2.23 to 2.18, were obtained with yields of ≥95% using ligand concentrations within 10−6–10−4M range. Thus, specific activities of 220 GBq/μmol could be achieved. Challenge studies with cysteine and histidine revealed
high stability for all of these radioactive complexes, and biodistribution studies in mice indicated a fast rate of blood
clearance and high rate of total radioactivity excretion occurring primarily through the renal-urinary pathway. In summary,
the ligands L1–L4 are potent chelators for the future functionalization of biomolecules labeling with fac-[188Re(CO)3(H2O)3]+. 相似文献
20.
Jun-Lan Wang Lan-Cui Zhang Xiao-Hui Li Cheng-Cheng You Zai-Ming Zhu 《Transition Metal Chemistry》2012,37(3):303-307
Three octamolybdate compounds, namely [Cu(H2biim)2]2[β-Mo8O26{Cu(H2biim)2}2][β-Mo8O26] (1), [{Fe(H2biim)2(Hbiim)}2(γ-Mo8O26)]·5H2O (2), and [{Co(H2biim)2(Hbiim)}2(γ-H2Mo8O26)]·5 H2O (3) (H2biim = 2,2′-biimidazole) have been hydrothermally synthesized from the reaction of mixtures of hexamolybdochromate ({CrMo6}), transition metal, and H2biim in acetate buffer solution, and characterized by physico-chemical and spectroscopic methods. They represent the first
examples of the conversion of hexamolybdochromate to octamolybdate. Single-crystal X-ray diffraction analysis reveals that
compound 1 is composed of a β-[Mo8O26]4− polyoxoanion bi-supported by two [Cu(H2biim)2]2+ complex cations, an isolated β-[Mo8O26]4− anion, and two [Cu(H2biim)2]2+ complex cations. The copper complex cations are situated at two different sites and associate with β-[Mo8O26]4− anions to give 2D layers, which are further packed into a 3D framework via strong hydrogen bonding interactions. Compounds
2 and 3 are isostructural, and contain a γ-[Mo8O26N2] unit and two symmetrical {M(H2biim)2(Hbiim)} (M=Fe or Co) fragments grafted onto the polyoxoanion through Mo–N bonds. The two compounds also exhibit 3D supramolecular
frameworks involving hydrogen bonding interactions. 相似文献