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1.
Grace O. Ogunlusi Jide Ige Olayinka A. Oyetunji Jonathan F. Ojo 《Transition Metal Chemistry》2009,34(5):483-491
The kinetics of the reactions between azido-pentacyanocobaltate(III), Co(CN)5N3
3−, and iron(II) polypyridyl complexes, Fe(LL)3
2+ (LL = bipy, phen), have been studied in both neutral and acidic aqueous solutions at I = 0.1 mol dm−3 NaCl. The reactions were carried out under pseudo-first-order conditions in which the concentration of Fe(LL)3
2+ was kept constant, and the second-order rate constants obtained for the reactions at 35 °C were within the range of 0.156–0.219
dm3 mol−1 s−1 for LL = bipy and 0.090–0.118 dm3 mol−1 s−1 for LL = phen. Activation parameters were measured for these systems. The dependence of reaction rates on acid was studied
in the range [H+] = 0.001–0.008 mol dm−3. The reaction in acid medium shows interesting kinetics. Two reactive species were identified in acid medium, namely, the
protonated cobalt complex and the azido-bridged binuclear complex. The electron-transfer process is proposed to go by mixed
outer- and inner-sphere mechanisms in acid medium, in which electron transfer through the bridged inner-sphere complex (k
5) is slower than through the outer-sphere path (k
4).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
2.
Oscar Picazo Ibon Alkorta José Elguero Markku R. Sundberg Jaana Valo Krzysztof Zborowski 《Structural chemistry》2009,20(4):557-563
A computational study of square planar organometallic complexes formed by the ligand 2,2′-bipyridine and all its possible
difluoro derivatives in analogous position of the aromatic rings (n,n′-difluoro-2,2′-bipyridine, where n = n′ = 3, 4, 5, and 6) and two M–X2 (M = Pd and Pt and X = F, Cl, Br, and I) fragments has been carried out amounting to a total of 80 complexes. Relationships
have been found between the chiral distinction energy and the different chemical moieties present. Using the statistical Free-Wilson
method, the relative energies between the diastereomeric complexes have been correlated with the position of the substituent,
the counter anion, and the central metal cation. 相似文献
3.
Qiaowen Chang Changyi Hu Jialin Chen Mingjin Xie Weiping Liu Qingsong Ye Yao Yu Xizhu Chen Liqiao Chen 《Transition Metal Chemistry》2011,36(4):337-340
A series of mixed-ligand complexes of tris(acetylacetonato) iridium(III) with N-heterocyclic ligands, namely [bis(acac-O,O′)(acac-C3)Ir(L)], where acac = acetyacetonato; L = 2-picoline (1), 3-picoline (2), 4-picoline (3), have been synthesized via the reaction
of [bis(acac-O,O′) (acac-C3)Ir(H2O)] with the corresponding ligand, respectively. Molecular structures of all complexes were determined by using single-crystal
X-ray diffraction. The results reveal that these complexes have slightly distorted octahedral coordination geometries. 相似文献
4.
Li-Juan Tian Zhi-Hong Ma Zhan-Gang Han Xue-Zhong Zheng Jin Lin 《Transition Metal Chemistry》2011,36(2):151-156
Reactions of the fulvenes C5H4C(R
1
R
2) [(R
1 = CH2CH3, R
2 = CH3 (1); R
1 = R
2 = C2H5 (2); R
1, R
2 = (CH2)4 (3), R
1,R
2 = (CH2)5 (4)] with Mo(CO)6 in refluxing xylene gave the corresponding cyclopentadienyl dimolybdenum carbonyl complexes [(η5-C5H4CR1′R2′Mo(CO)3]2 [(R
1′ = CH2CH3, R
2′ = CH3 (5); R
1′ = R
2′ = C2H5 (6); R
1′, R
2′ = CH(CH2)3 (7); R
1′, R
2′ = CH(CH2)4 (8)], which were characterized by elemental analysis, IR and 1H NMR spectra. The molecular structures were determined by single-crystal X-ray diffraction. The results indicated the exocyclic
double bond of the ligands 1 and 2 changed into a single bond and the exocyclic double bond of the ligands 3 and 4 underwent a double-bond isomerization process. 相似文献
5.
Shinya Hayami Yoshihiro Kojima Daisuke Urakami Kazuchika Ohta Katsuya Inoue 《Monatshefte für Chemie / Chemical Monthly》2009,34(4):829-838
Abstract
Metal complexes with long alkyl chains [Co(C16-terpy)3](BF4)2 (1), [Fe(C16-terpy)2](BF4)2 (2), [Co(C16-terpy)2](BPh4)2 (3), [Co(C14-terpy)2](BF4)2 (4), and [Fe(C12C10C5-terpy)2](BF4)2 (5) were synthesized and their physical properties characterized, where C16-terpy, C14-terpy, and C12C10C5-terpy are 4′-hexadecyloxy-2,2′:6′,2′′-terpyridine, 4′-tetradecyloxy-2,2′:6′,2′′-terpyridine, and 4′-5′′′-decyl-1′′′-heptadecyloxy-2,2′:6′,2″-terpyridine, respectively. Complexes 1, 2, and 5 exhibited liquid–crystal properties in the temperature ranges of 371–528 K and 466–556 K, and 88–523 K, respectively. Variable-temperature magnetic susceptibility measurements revealed that the Co(II) complexes 1 and 4 exhibited unique spin transitions (T 1/2↓ = 217 K and T 1/2↑ = 260 K for 1 and T 1/2↓ = 250 K and T 1/2↑ = 307 K for 4), so-called ‘reverse spin transition,’ induced by structural phase transitions. Complex 3 exhibited gradual spin-crossover behavior (T 1/2 = 160 K.), and complex 5 exhibited spin transitions (T 1/2↑ = 288 K and T 1/2↓ = 284 K) at the liquid crystal transition temperature. Compounds with multifunction, i.e., magnetic and liquid–crystal properties, are important in the development of molecular materials. 相似文献6.
Santanu Mandal Ashok Kumar Rout Guillaume Pilet Debasis Bandyopadhyay 《Transition Metal Chemistry》2009,34(7):719-724
Two new mononuclear complexes of copper(II), namely [CuL2] (1) and [CuL′2] (2) have been synthesized by reacting copper perchlorate with furfurylamine and salicylaldehyde or 2-hydroxyacetophenone, where
L = (2-hydroxybenzyl-2-furylmethyl)imine and L′ = (2-hydroxymethylbenzyl-2-furylmethyl)imine, the respective asymmetric bidentate
Schiff bases that are formed in situ to bind the Cu(II) ion. The complexes have been characterized by elemental analysis,
IR spectroscopy and single crystal X-ray diffraction studies. Structural studies reveal that the mononuclear units of both
the complexes (1) and (2) adopt square planar geometry supported by weak intermolecular C–H···π interactions. 相似文献
7.
A series of hybrid mesoporous SBA-15 materials containing four iron(III) Schiff base complexes of the type [FeL
x
(NO3)] (x = 4–7, L = N,N′-bis(salicylidene)ethylenediamine, N,N′-bis(salicylidene)diethylenetriamine, N,N′-bis(salicylidene)o-phenylenediamine, N,N′-bis(3-nitro-salicylidene)ethylenediamine) was synthesized by a post-grafting route. The XRD, N2 adsorption/desorption and TEM measurements confirmed the structural integrity of the mesoporous hosts, and the spectroscopic
characterization techniques (FT-IR, UV–vis spectroscopy, 1H NMR) confirmed the ligands and the successful anchoring of iron(III) Schiff base complexes over the modified mesoporous
support. Quantification of the supported ligand and metal was carried out by TG/DSC and ICP-AES techniques. The catalyst FeL7-SBA resulting from N,N′-bis(3-nitro-salicylidene)ethylenediamine) ligand was considerably active for the aerobic epoxidation
of styrene, in which the highest conversion of styrene reached 83.6%, and the selectivity to styrene oxide was 83.0%. Moreover,
it was also found that the catalytic activity increases with the decrease in the electron-donating ability of the Schiff bases,
and the selectivity varies according to the types of substituents in the ligands. 相似文献
8.
Rui-Hao Yu Yong-Jun Zheng Yan-Tuan Li Zhi-Yong Wu Cui-Wei Yan 《Transition Metal Chemistry》2012,37(4):399-406
Two complexes of general formula, [M(DABTA)]NO3 [M = CuII
(1) or NiII
(2), DABTA = N,N′-(4,4′-bithiazole-2,2′-diyl)diacetimidamide], have been synthesized and characterized by elemental analyses, molar conductivity
measurements, IR and electronic spectra studies and single-crystal X-ray diffraction. The crystal structures show that the
two complexes have similar molecular structures in which each metal atom has a square-planar coordination environment. Hydrogen
bonding interactions link each complex into a 2-D infinite network. The DNA-binding properties and cytotoxicities of the complexes
were investigated. The results suggest that the two complexes can interact with DNA by intercalation, with binding affinities
following the order of 1 > 2, which is consistent with their in vitro cytotoxicities. 相似文献
9.
Two stable thiazolylazo anion radical complexes of ruthenium(II), [Ru(L1•−)(Cl)(CO)(PPh3)2] (1) and [Ru(L2•−)(Cl)(CO)(PPh3)2] (2) (where L1 = 2′-Thiazolylazo-2-imidazole and L2 = 4-(2′-Thiazolylazo)-1-n-hexadecyloxy-naphthalene), have been synthesized
and characterized by spectroscopic and electrochemical techniques. The radical nature of the complexes has been confirmed
from their room temperature magnetic moments and X-band ESR spectra. The radical complexes display a moderately intense (ε ~ 104 M−1 cm−1) and relatively broad band in 430–460 nm region. In the microcrystalline state, complexes (1) and (2) display strong ESR
signals at g = 1.951 and g = 1.988, respectively. In CH2Cl2 solution, complexes (1) and (2) show a quasireversible one-electron response near −0.64 and −0.59 V, respectively, versus
Ag/AgCl due to the radical redox couple [RuII(L)(Cl)(CO)(PPh3)2]/[RuII (L•−)(Cl)(CO)(PPh3)2]. 相似文献
10.
Crystalline substances formed in the (MF)1−x
−(M′F)
x
−SbF3−H2O systems (M, M′=Na, K, Rb, Cs, and NH4;x=0 to 1) were investigated by121,123Sb NQR spectroscopy at 77 K. The formation of individual SbIII complexes NaCs3Sb4F16·H2O and NaKSbF5·1.5H2O, and statistically disordered mixed crystals M1−x
−M′
x
−SbF4 (M, M′=K, Rb, Cs, and NH4) was established.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 109–112, January, 1999. 相似文献
11.
A. Zalga Z. Moravec J. Pinkas A. Kareiva 《Journal of Thermal Analysis and Calorimetry》2011,105(1):3-11
The preparation and characterization of the M′–M′′–O nitrate–tartrate (M′ = Ca, Ba, Gd and M′ = W, Mo) precursor gels synthesized
by simple, inexpensive, and environmentally benign aqueous sol–gel method is reported. The obtained gels were studied by thermal
(TG/DSC) analysis. TG/DSC measurements revealed the possible decomposition pathway of synthesized M′–M′′–O nitrate–tartrate
gels. For the synthesis of different metal tungstates and molybdates, the precursor gels were calcined at different temperatures
(650, 800, and 900 °C). According to the X-ray diffraction (XRD) analysis data, the crystalline compounds CaMo1-x
W
x
O4 doped with Ce3+ ions, BaMo1-x
W
x
O4 doped with Eu3+ ions and Gd2Mo3O12 were obtained from nitrate–tartrate gels annealed at 650–900 °C temperatures. The XRD data confirmed that the fully crystalline
single-phase powellite, scheelite, or Gd2(MoO4)3 structures were formed already at 650 °C. Therefore, the suggested sol–gel method based on the complexation of metal ions
with tartaric acid is suitable for the preparation of mixed tungstates–molybdates at relatively low temperature in comparison
with solid-state synthesis. 相似文献
12.
Ahmed M. El-Hendawy Ahmed M. Fayed Mohamed R. Mostafa 《Transition Metal Chemistry》2011,36(4):351-361
The complexes [M(Hdamsm)2]X·H2O (M = Fe, X = NO3; M = Ru, X = Cl), [Ru(Hdamsm)(PPh3)2X′](X′ = Cl, Br), and [VO(Hdamsm)(acac)] (H2damsm = diacetylmonoxime Schiff base of S-methyldithiocarbazate, Hacac = acetylacetone) have been prepared and characterized by spectroscopic techniques. Their redox
properties were investigated by cyclic voltammetry. The X-ray crystal structure of [Fe(Hdamsm)2]NO3.H2O has been determined and shows that the complex has a distorted octahedral geometry in which the Hdamsm behaves as a monoanionic
NNS tridentate ligand coordinating via oxime nitrogen, hydrazinic imine nitrogen, and thiolate sulfur. The reactivity of these
complexes toward oxidation of alcohols in the presence of t-BuOOH and H2O2 as co-oxidants is reported. 相似文献
13.
Dong-Yu Lv Zhu-Qing Gao Jin-Zhong Gu Jian-Zhao Liu Wei Dou 《Transition Metal Chemistry》2011,36(3):275-281
Two Mn(II) coordination polymers, namely [Mn(bpda)]
n
(1) and [Mn(bpda)(bpy)0.5]
n
(2) (H2bpda = 1,1′-biphenyl-3,3′-dicarboxylic acid and bpy = 4,4′-bipyridine), have been synthesized from H2bpdc, bpy, and MnSO4·2H2O under hydrothermal conditions. The complexes were characterized by physicochemical and spectroscopic methods, as well as
by X-ray crystallography. Compound 1 possesses a 3D structure consisting of carboxylate-bridged edge-sharing Mn–O–Mn double chains. Compound 2 features a 3D open structure with a dinuclear Mn(II) secondary building unit. Magnetic susceptibility measurements of compounds
1 and 2 exhibit antiferromagnetic interactions between the nearest Mn(II), with J = –11.3 cm−1 and g = 2.12 for 1, and J = –13.5 cm−1 and g = 2.12 for 2. 相似文献
14.
Two new neodymium complexes, [Nd2(abglyH)6(2,2′-bipy)2(H2O)2] · 4H2O 1 and {[Nd(abglyH)3(H2O)2] · (4,4′-bipy) · 7H2O}n
2 (abglyH2 = N-P-acetamidobenzenesulfonyl-glycine acid, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine), have been synthesized and
their structures have been measured by X-ray crystallography. In 1, nine-coordinated Nd(III) ions are bridged by two syn–syn bidentate and two tridentate bridging carboxylate groups from four different abglyH− anions to form dinuclear motifs, which are further connected into a 3-D supramolecular framework via hydrogen bonds between
the binuclear motifs and the uncoordinated water molecules. In 2, eight-coordinated Nd(III) ions are linked by six carboxylate groups adopting a syn–syn bidentate bridging fashion to form a 1-D inorganic–organic alternating linear chain. These polymeric chains generate microchannels
extending along the a direction, and these cavities are occupied by discrete tetradecameric water clusters, which interact with their surroundings
and finally furnish the 3-D supramolecular network via hydrogen bonds. At the same time, π–π stacking interactions between
benzene rings from abglyH− anions also play an important role in stabilizing the network. 相似文献
15.
The mutual influence of the atoms on the composition of solid fluorine-containing antimony(iii) complexes formed in aqueous solutions in the (MF)
x
−(M′F)
n−x
−SbF3 (M, M′=Na, K, Rb, Cs, and NH4;n=1, 2;x=0 to 2), (KNO2)
n
−(KY)
n
−SbF3 (Y=F, Cl, SO4;n=0.5, 1), and K2SbF5−K2SbCl5 systems was investigated by elemental, X-ray, and thermogravimetric analyses and by IR and121,123Sb NQR spectroscopy. The isomorphism conditions for fluorine-containing antimony(iii) compounds resulting in the formation of complexes NaM′SbF5·1.5H2O (M′=K and Rb), K2SbF5·1.5H2O, NaCs3Sb4F16·H2O, KsbF3Cl, K2SbF2Cl3 with constant compositions, continuous M
x
M′2−x
SbF5 (0<x<2) and limited M
x
M′1−x
SbF4 (0.25<x<0.75; M, M′=K, Rb, Cs, and NH4) solid solutions or LiF+MSbF4 (M=Na, K, Rb, and Cs), M2SbF5+Cs2SbF5 (M=Na and K) and MSbF4+NaSbF4 (M=Rb and NH4) mechanical mixtures were determined.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 103–108, January, 1999. 相似文献
16.
Solvothermal synthesis and structures of three novel heterometallic microporous coordination polymers assembled from 2-hydroxy-nicotinic acid 总被引:1,自引:0,他引:1
Hua Hong Zou Shu Hua Zhang Yu Xiao Chao Feng Yin Guang Wang 《Structural chemistry》2011,22(1):135-140
Abstract
Three novel heterometallic microporous coordination polymers {M(Hnico)3M′} n (1, M = Co, M′ = K; 2, M = Ni, M′ = K; 3, M = Co, M′ = Na, Hnico is the anion of 2-hydroxy-nicotinic acid, where the proton is transferred from the phenolate hydroxy group to the nitrogen atom of imine pyridine ring) were synthesized by hydrothermal reaction between M(Ac)2·4H2O, M′OH and a multifunctional organic aromatic H2nico ligand and characterized by IR spectrum, elemental analysis, raman spectrum and the single crystal X-ray diffractions. In complexes 1–3, the M2+ ions linked three different Hnico ligand formed [M(Hnico)3]− subunit which further interlinked the six-coordination M′+ cation constructed 3D network. The network topology of 1–3 can be simplified a rare 3D (4,4)-connected (41263) net. 相似文献17.
S. Vairam T. Premkumar S. Govindarajan 《Journal of Thermal Analysis and Calorimetry》2010,101(3):979-985
Hydrazine forms two different types of complexes with divalent metal ions and pyromellitic acid (H4pml) in aqueous medium: (i) hydrazinium complexes of formulae, (N2H5)2M(pml)·xH2O, where x = 3 for M=Ni and x = 4 for M=Co or Zn, and (N2H5)2Mn(H2pml)2, at pH 4.5, (ii) neutral hydrazine complexes with formulae, M2(pml)(N2H4)
n
·xH2O where M=Co or Ni when n = 4 and x = 5 or 4 and M=Zn or Cd when n = 2, and x = 4 or 3 at pH 7, and M(H2pml)(N2H4)·xH2O where x = 4; M=Cu and x = 0; M=Hg, at pH 3, 7.5, respectively. All the complexes are insoluble in water, alcohol and ether. The N–N stretching frequency
(990–1,007 cm−1 for coordinated hydrazinium ion and 956–985 cm−1 for bridged neutral hydrazine) indicates the nature of hydrazine present in the complexes. Simultaneously TG-DTA analysis
indicates that hydrazinium complexes undergo dehydration and dehydrazination in a single step endothermally in the range of
289–300 °C whereas neutral hydrazine complexes undergo endothermic dehydration (~100 °C) followed by exothermic dehydrazination
in the temperature range, 253–332 °C. The anhydrous metal carboxylates further decompose exothermally to leave the respective
metal oxides or metal carbonates except zinc, which gives its oxalate as the end product. X-ray powder patterns indicate that
even the complexes with the same formulation possess no isomorphism. 相似文献
18.
Xinxin Xu Xiaoguang Sang Xiaoxia Liu Xia Zhang Ting Sun 《Transition Metal Chemistry》2010,35(4):501-506
Two new supramolecular metal–organic complexes have been synthesized under hydrothermal conditions. Complex 1 exhibits a three-dimensional supramolecular network, constructed from [Co2(H3BPTC)2(phen)2] (H4BPTC = 3,3′4,4′-benzophenone tetracarboxylate acid, phen = 1,10-phenanthroline) discrete units. Complex 2 similarly exhibits discrete [Cu2(DPA)2(bipy)2(H2O)2] (DPA = 1,1′-biphenyl-2,2′-dicarboxylate acid, bipy = 2,2′-bipyridine) units, which are linked to form a three-dimensional
supramolecular network through π–π interactions. It is interesting that during the synthesis of complex 1, the H4BPTC ligands undergo partial decomposition to give 1,2,4-benzenetricarboxylate (H3BTC) ligands, which react with Co to form [Co3(BTC)2]n (3). Complex 3 shows a three-dimensional covalent network. The magnetic properties of complexes 1 and 2 have been studied. 相似文献
19.
Li Xu Yang-Yin Xie Nan-Jing Zhong Zhen-Hua Liang Juan He Hong-Liang Huang Yun-Jun Liu 《Transition Metal Chemistry》2012,37(2):197-205
Two ruthenium(II) polypyridyl complexes, namely [Ru(phen)2(DMDPPZ)](ClO4)2
1 (phen = 1,10-phenanthroline, DMDPPZ = 3,6-dimethyldipyrido[3,2-a:2′,3′-c]phenazine) and [Ru(dmp)2(DMDPPZ)](ClO4)2
2 (dmp = 2,9-dimethyl-1,10-phenanthroline), have been synthesized and characterized. The DNA-binding properties of the complexes
were investigated by spectrophotometric methods, viscosity measurements, and photoactivated cleavage studies. The DNA-binding
constants for complexes 1 and 2 have been determined as 8.78 (±0.94) × 105 M−1 (s = 3.02) and 1.26 (±0.35) × 105 M−1 (s = 1.69), respectively. The results suggest that these complexes bind to calf thymus DNA through intercalation. When irradiated
at 365 nm, the complexes promote the photocleavage of pBR322 DNA, and complex 1 cleaves DNA more effectively than complex 2 under comparable experimental conditions. The cytotoxicities of complexes 1 and 2 have been evaluated by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) method. Complex 2 shows higher anticancer potency than complex 1 against four tumor cell lines. The apoptosis-inducing activity was assessed by acridine orange/ethidium bromide staining
assay, and the antioxidant activities of these complexes against hydroxyl radical were also explored. 相似文献
20.
Shinya Hayami Yoshihiro Kojima Daisuke Urakami Kazuchika Ohta Katsuya Inoue 《Monatshefte für Chemie / Chemical Monthly》2009,140(7):829-838
Abstract Metal complexes with long alkyl chains [Co(C16-terpy)3](BF4)2 (1), [Fe(C16-terpy)2](BF4)2 (2), [Co(C16-terpy)2](BPh4)2 (3), [Co(C14-terpy)2](BF4)2 (4), and [Fe(C12C10C5-terpy)2](BF4)2 (5) were synthesized and their physical properties characterized, where C16-terpy, C14-terpy, and C12C10C5-terpy are 4′-hexadecyloxy-2,2′:6′,2′′-terpyridine,
4′-tetradecyloxy-2,2′:6′,2′′-terpyridine, and 4′-5′′′-decyl-1′′′-heptadecyloxy-2,2′:6′,2″-terpyridine, respectively. Complexes
1, 2, and 5 exhibited liquid–crystal properties in the temperature ranges of 371–528 K and 466–556 K, and 88–523 K, respectively. Variable-temperature
magnetic susceptibility measurements revealed that the Co(II) complexes 1 and 4 exhibited unique spin transitions (T
1/2↓ = 217 K and T
1/2↑ = 260 K for 1 and T
1/2↓ = 250 K and T
1/2↑ = 307 K for 4), so-called ‘reverse spin transition,’ induced by structural phase transitions. Complex 3 exhibited gradual spin-crossover behavior (T
1/2 = 160 K.), and complex 5 exhibited spin transitions (T
1/2↑ = 288 K and T
1/2↓ = 284 K) at the liquid crystal transition temperature. Compounds with multifunction, i.e., magnetic and liquid–crystal properties,
are important in the development of molecular materials.
Graphical Abstract
相似文献
Shinya HayamiEmail: |