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1.
Qing Yuan Kai Cai Zhao-Peng Qi Zhen-Shuai Bai Zhi Su Wei-Yin Sun 《Journal of inorganic biochemistry》2009,103(8):1156-1161
Two new homo- and hetero-dinuclear complexes, [Cu2L(im)](ClO4)34H2O (1) and [CuZnL(im)](ClO4)34H2O (2) (where Im=1H-1midazole and L = 3, 6, 9, 16, 19, 22-hexaaza-6, 19-bis(1H-imidazol-4-ylmethyl)tricycle[22, 2, 2, 211,14]triaconta-1, 11, 13, 24, 27, 29-hexaene) were synthesized and characterized as model compounds for the active site of copper(II)–zinc(II) superoxide dismutase (Cu2Zn2–SOD). X-ray crystal structure analysis revealed that the metal centers in both complexes exhibit distorted trigonal-bipyramid coordination geometry and the CuCu and CuZn distances are both 6.02 Å. Magnetic and ESR spectral measurements of 1 showed antiferromagnetic exchange interactions between the imidazolate-bridged Cu(II) ions. The ESR spectrum of 2 displays typical signals of mononuclear Cu(II) complex, demonstrating the formation of heterodinuclear complex 2 rather than a mixture of homodinuclear Cu(II)/Zn(II) complexes. pH-dependent ESR and UV–visible spectral measurements manifest that the imidazolate exists as a bridging ligand from pH 6 to 11 for both complexes. The IC50 values of 1.96 and 1.57 μM [per Cu(II) ion] for 1 and 2 suggest that they are good models for the Cu2Zn2–SOD. 相似文献
2.
Tanmay K. Jana Rabindranath Pradhan Subhajit Dinda Corine Simonnet Inhar Imaz Léopold Fournès Francis Sécheresse Ramgopal Bhattacharyya 《Inorganica chimica acta》2009,362(10):3583-3594
Iron (II) and iron (III) complexes, [FeII(DEDTC)2(dppe)] · CH2Cl2 (1), [FeII(ETXANT)2(dppe)] (2) (DEDTC = diethyldithiocarbamate, ETXANT = ethyl xanthate, dppe = 1,2-bis (diphenylphosphino) ethane), and [FeIII(DEDTC)2(dppe)] [FeIIICl4] (3) have been synthesized and characterized. Since 3 contains two magnetic centers, an anion metathesis reaction has been conducted to replace the tetrahedral FeCl4− by a non-magnetic BPh4− ion producing [FeIII(DEDTC)2(dppe)]BPh4 (4) for the sake of unequivocal understanding of the magnetic behavior of the cation of 3. With the similar end in view, the well-known FeCl4− ion, the counter anion of 3, is trapped as PPh4[FeIIICl4] (5) and its magnetic property from 298 to 2 K has been studied. Besides the spectroscopic (IR, UV-Vis, NMR, EPR, Mass and XPS) characterization of the appropriate compounds, especially 2, others viz. 1, 3 and 4 have been structurally characterized by X-ray crystallography. While FeII complexes, 1 and 2, are diamagnetic, the FeIII systems, namely the cations of 3, and 4 behave as low-spin (S = 1/2) paramagnetic species from 298 to 50 K. Below 50 K 3 shows gradual increase of χMT up to 2 K suggesting ferromagnetic behavior while 4 exhibits gradual decrease of magnetic moment from 60 to 2 K, indicating the occurrence of weak antiferromagnetic interaction. These conclusions are supported by the Mössbauer studies of 3 and 4. The Mössbauer pattern of 1 exhibits a doublet site for diamagnetic (2-400 K) FeII. The compounds 1, 2 and 4 encompass interesting cyclic voltammetric responses involving FeII, FeIII and FeIV. 相似文献
3.
《Inorganica chimica acta》2006,359(5):1559-1572
Degradation reactions of scorpionates were observed in the presence of transition metal salts MX2 to give complexes of transition metal and pyrazole derivatives. Otherwise, pyrazolato complexes of transition metals and weakly coordinating anions such as nitrates have been synthesized from transition metal nitrates and 3-phenyl- and 4-phenyldiazo-pyrazole. A number of complexes with pyrazole derivatives as ligands, [Zn(3-tBupzH)2Cl2], [Fe2(3-Phpz)6Cl4], [Cu(pzH)4Br2], [Ni(py)2(pzH)2Cl2], [Li(THF)4][Ti2(μ-pz)3Cl4(NMe2)2], [Zn2(μ-3-Phpz)2(3-PhpzH)2][(NO3)2], [M(3-PhpzH)4(NO3)2] (M = Co, Ni, Cu, Zn, Cd), [Zn(3-PhpzH)2(NO3)2], [Zn(4-PhNNpzH)2(NO3)2](H2O), and [Cd(4-PhNNpzH)2(NO3)2(H2O)2], have been crystallized and characterized by single-crystal X-ray diffraction. 相似文献
4.
Shaun Richard Presow 《Inorganica chimica acta》2011,374(1):226-239
Two new o-aminothiophenol type ligands have been synthesized, namely 1,3-propanediamine-N,N′-bis(benzenethiol), H4(1L), and 1,2-bis(2-mercapto-3,5-di-tert-butylaniline)ethane, H4(2L). The reactions of these ligands with FeBr2 in dry acetonitrile in the presence and absence of air (and other oxidants such as iodine) afforded seven new complexes which were characterized by single-crystal X-ray crystallography and Mössbauer spectroscopy (as well as EPR- and UV-Vis spectroscopies). Their magnetochemistry has been studied and their electronic structures have been established and verified by broken symmetry (BS) density functional theoretical (DFT) calculations using the B3LYP functional. The ligands are redox-active and the o-iminothiophenolate(2-)-o-iminothiobenzosemiquinonate(1-) oxidation levels are chemically readily accessible. The complexes characterized comprise the dimers [FeIII(1L)]2 (ST = 0) (1); [FeIII(2L)]2 (ST = 0) (2), and the mononuclear, five coordinate species: [FeIII(1L)I] (ST = 1/2) (3); [FeIII(2L)I] (ST = 1/2) (4); [FeII(1L){P(CH3)3}] (ST = 0) (5); [FeII(2L){P(C6H5)3}] (ST = 0) (6), and [FeIII(2)(tpy)] (ST = 1) (7). (tBupy) represents 4-tert-butylpyridine and (2)3− is the π radical trianion of the one-electron reduced (2Lgma)2− which in turn is the oxidized form of (2L)4− (−4H+, −2e). 相似文献
5.
Mitchell R. Malachowski Mark E. Adams Ryan White Arnold L. Rheingold Richard S. Kelly 《Inorganica chimica acta》2009,362(4):1247-1252
Two nitrogen and sulfur containing ligands, 1-methyl-4-((4-methylimidazol-5-yl)methylthio)benzene (NS-mim) (1) and 1-methyl-4-(2-pyridylmethylthio)benzene (NS-mpy) (2) were synthesized and a series of their Cu(II) complexes, 3-10, prepared. The imidazole-containing complexes (3-6) have the form [Cu(NS-mim)2(solvent)2](X)2 where X = ClO4, BF4and [Cu(NS-mim)2(Y)2] where Y = Cl or Br and the pyridine-containing complexes (7-10) have the form [Cu(NS-mpy)2]X2 (where X = ClO4, BF4) and [Cu2(NS-mpy)2Y4] (where Y = Cl or Br). These complexes were characterized by a combination of elemental analysis, FAB-MS and electrochemistry. The X-ray structure of the imidazole-containing [Cu(NS-mim)2(DMF)2](ClO4)2 (3) was determined and it showed the copper(II) coordinated only by the nitrogen donors while the sulfurs remain uncoordinated. In comparison, the X-ray structure of the pyridine-containing [Cu2(NS-mpy)2(Cl)4] (9) shows a dinuclear copper(II) complex with the nitrogens and the sulfurs coordinated along with a terminal chloride and two μ-chloro atoms bridging the coppers. Cyclic voltammetry studies indicated that the complexes undergo quasi-reversible one-electron reductions in acetonitrile at potentials between 0.31 and 0.51 V versus SCE. The complexes were found to be active for the oxidation of di-tert-butyl catechol (DTBC) with the rate dependent on the ligand and the counterion present. 相似文献
6.
Christopher E. Anson 《Inorganica chimica acta》2005,358(13):3967-3973
The synthesis and structural characterization of the copper salts [Cu8(benzoate)8(THF)6] (1), [Cu2{(CO2)2C6H2(Boc)2}dppm2]2 (2) and [Cu2{(CO2)2C10H4(Boc)2}dppm2]2 (3) [Boc = tert-butoxycarbonyl, dppm = 1,2-bis(diphenylphosphino)methane] prove that cyclic organic anhydrides and dianhydrides readily insert into the Cu-O bond of [CuOtBu] forming carboxylate ligands with ester functionalities in the ligand periphery. [Mn3(o-Boc-benzoate)6(DME)2] (4) (DME = 1,2-dimethoxyethane) was synthesized by the metathesis reaction of [Cu(I)(o-Boc-benzoate)] with MnCl2. 相似文献
7.
Lukasz Ponikiewski 《Inorganica chimica acta》2008,361(1):43-48
The synthesis and structural characterization of the copper salts [Cu2(2-Boc-benzoate)4(dme)2] (1), [Cu(2-Boc-benzoate)2(tmeda)] (2), [Cu2(2-Boc-benzoate)2(dppm)] (3), [Cu(2-Boc-nicotinate)(PPh3)2] (4), [Cu2{2-Boc-5,6-anhydride-naphthylcarboxylate}2(dppm)2] (5) [dme = 1,2-dimethoxyethane, dppm = bis(diphenylphosphino)methane, tmeda = N,N′-tetramethylethylenediamine, Boc = tert-butoxycarbonyl] prove that cyclic organic anhydrides and dianhydrides readily insert into the Cu-O bond of [CuOtBu] forming carboxylate ligands with ester functionalities in the ligand periphery. [Sb(CO2Ph-o-CO2Me)2(OMe)(tmeda)] (6) was synthesised by insertion reaction of Sb(OMe)3 with phthalic anhydride. 相似文献
8.
Tuning the substituents of triazoles, we obtained di- and tri-nuclearic triazole-nickel complexes [Ni2(deatrz)4(H2O)5](SO4)2 · 7H2O (1) and [Ni3(dmtrz)6(H2O)6](SO4)3 · 21H2O (2) (deatrz = 3,5-diethanyl-4-amino-1,2,4-triazole; dmtrz = 3,5-dimethanyl-1,2,4-triazole). The X-ray single-crystal diffraction results reveal that sulfate anions and water clusters form supramolecular networks in both complexes. In 1, a supramolecular two-dimensional structure was fabricated by nano-sized grid with novel tetramer water rings templated via binuclear-nickel(II) cations, while in 2, water molecules and sulfate anions construct the first sulfate-water three-dimensional supramolecular network as host to encapsulate trinuclear-nickel guests. 相似文献
9.
Franz A. Mautner Jörg H. Albering Febee R. Louka Salah S. Massoud 《Inorganica chimica acta》2011,365(1):290-296
Three mono-nuclear copper(II) complexes [Cu(tepza)X]ClO4 (X = Cl, 1; X = NCS, 2; X = dca, 3) and two dinuclear bridging complexes [Cu2(tepza)2(μ-C4O4)](ClO4)2·H2O(4) and [Cu2(tepza)2(μ-C5O5)](ClO4)2(5) where tepza = tris[2-ethyl(1-pyrazolyl)]amine, dca = dicyanamide, C4O42− = 3,4-dihydroxycyclobut-3-ene-1,2-dionate (squarate dianion) and C5O52− = 4,5-dihydroxycyclopent-4-ene-1,2,3-trionate (croconate dianion) were synthesized and structurally characterized by IR and UV-Vis spectroscopy as well as by single X-ray crystallography. In the solid state, the geometry of copper(II) centers in these complexes are as follows: close to SP in 2, distorted TBP in 3, predominant SP in 4, and distorted octahedral in 5, whereas in solution distorted SP geometry was generally found. The squarato and the croconato dianions in complexes 4 and 5 are bridging the two copper(II) centers in cis-bis-monodentate and bis-bidentate bonding modes, respectively. Magnetic susceptibility measurements at variable temperatures (2-300 K) reveal the weak antiferromagnetic coupling in the two bridging dinuclear complexes 4 (J = −24.9 cm−1) and 5 (J = −3.1 cm−1). 相似文献
10.
Two new ruthenium complexes [Ru(bpy)2(mitatp)](ClO4)21 and [Ru(bpy)2(nitatp)](ClO4)22 (bpy = 2,2′-bipyridine, mitatp = 5-methoxy-isatino[1,2-b]-1,4,8,9-tetraazatriphenylene, nitatp = 5-nitro-isatino[1,2-b]-1,4,8,9-tetraazatriphenylene) have been synthesized and characterized by elemental analysis, 1H NMR, mass spectrometry and cyclic voltammetry. Spectroscopic and viscosity measurements proved that the two Ru(II) complexes intercalate DNA with larger binding constants than that of [Ru(bpy)2(dppz)]2+ (dppz = dipyrido[3,2-a:2′,3′-c]phenazine) and possess the excited lifetime of microsecond scale upon binding to DNA. Both complexes can efficiently photocleave pBR322 DNA in vitro under irradiation. Singlet oxygen (1O2) was proved to contribute to the DNA photocleavage process, the 1O2 quantum yields was determined to be 0.43 and 0.36 for 1 and 2, respectively. Moreover, a photoinduced electron transfer mechanism was also found to be involved in the DNA cleavage process. 相似文献
11.
The synthesis and crystal structure of two new complexes (Zn and Mn) containing tetrazolyl ligands are described. In situ [2+3] cycloaddition reactions of fipronil, (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile) with sodium azide in the presence of ZnCl2 or MnCl2 as a Lewis acid (Demko-Sharpless tetrazole synthesis method) under hydrothermal (solvothermal) reaction conditions gave [Zn(L)2](H2O)2] · H2O, 1 and [Mn(L)2](H2O)2] · H2O, 2, (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole). The central metals in both complexes are six coordinated, which connected by two water molecules, two nitrogen atoms from different tetrazolyl groups and two nitrogen atoms from pyrazolyl rings respectively. Photoluminescence studies reveal that both title complexes exhibit strong blue fluorescent emissions at λmax = 383 nm for 1 and 411 nm for 2 respectively in the solid state at room temperature. 相似文献
12.
Xavier FR Peralta RA Bortoluzzi AJ Drago V Castellano EE Haase W Tomkowicz Z Neves A 《Journal of inorganic biochemistry》2011,105(12):1740-1752
In this work we report on the synthesis, crystal structure, and physicochemical characterization of the novel dinuclear [FeIIICdII(L)(μ-OAc)2]ClO4·0.5H2O (1) complex containing the unsymmetrical ligand H2L = 2-bis[{(2-pyridyl-methyl)-aminomethyl}-6-{(2-hydroxy-benzyl)-(2-pyridyl-methyl)}-aminomethyl]-4-methylphenol. Also, with this ligand, the tetranuclear [Fe2IIIHg2II(L)2(OH)2](ClO4)2·2CH3OH (2) and [FeIIIHgII(L)(μ-CO3)FeIIIHgII(L)](ClO4)2·H2O (3) complexes were synthesized and fully characterized. It is demonstrated that the precursor [FeIII2HgII2(L)2(OH)2](ClO4)2·2CH3OH (2) can be converted to (3) by the fixation of atmospheric CO2 since the crystal structure of the tetranuclear organometallic complex [FeIIIHgII(L)(μ-CO3)FeIIIHgII(L)](ClO4)2·H2O (3) with an unprecedented {FeIII(μ-Ophenoxo)2(μ-CO3)FeIII} core was obtained through X-ray crystallography. In the reaction 2 → 3 a nucleophilic attack of a FeIII-bound hydroxo group on the CO2 molecule is proposed. In addition, it is also demonstrated that complex (3) can regenerate complex (2) in aqueous/MeOH/NaOH solution. Magnetochemical studies reveal that the FeIII centers in 3 are antiferromagnetically coupled (J = − 7.2 cm− 1) and that the FeIII-OR-FeIII angle has no noticeable influence in the exchange coupling. Phosphatase-like activity studies in the hydrolysis of the model substrate bis(2,4-dinitrophenyl) phosphate (2,4-bdnpp) by 1 and 2 show Michaelis-Menten behavior with 1 being ~ 2.5 times more active than 2. In combination with kH/kD isotope effects, the kinetic studies suggest a mechanism in which a terminal FeIII-bound hydroxide is the hydrolysis-initiating nucleophilic catalyst for 1 and 2. Based on the crystal structures of 1 and 3, it is assumed that the relatively long FeIII…HgII distance could be responsible for the lower catalytic effectiveness of 2. 相似文献
13.
A new series of dinuclear squarato-bridged nickel(II) and copper(II) complexes [Ni2(2,3,2-tet)2(μ1,3-C4O4)(H2O)2](ClO4)2 (1), [Ni2(aepn)2(μ1,3-C4O4)(H2O)2](ClO4)2 (2), [Cu2(pmedien)2(μ1,3-C4O4)(H2O)2](ClO4)2.4H2O (3) and [Cu2(DPA)2(μ1,2-C4O4)(H2O)2](ClO4)2 (4) where is the dianion of 3,4-dihydroxycyclobut-3-en-1,2-dione (squaric acid), 2,3,2-tet = 1,4,8,11-tetraazaundecane, aepn = N-(2-aminoethyl)-1,3-propanediamine, pmedien = N,N,N′,N″,N″-pentamethyldiethylenetriamine and DPA = di(2-pyridylmethyl)amine were synthesized and structurally characterized by X-ray crystallography. The spectral and structural characterization as well as the magnetic behaviour of these complexes is reported. In this series, structures consist of the groups as counter ions and the bridging the two M(II) centers in a μ-1,3- (1-3) and in a μ-1,2-bis(monodentate) (4) bonding fashions. The coordination geometry around the Ni(II) ions in 1 and 2 is six-coordinate with distorted octahedral environment achieved by N atoms of the amines and by one or two oxygen atoms from coordinated water molecules, respectively. In the Cu(II) complexes 3 and 4, a distorted square pyramidal geometry is achieved by the three N-atoms of the aepn or DPA and by an oxygen atom from a coordinated water molecule. The electronic spectra of the complexes in aqueous solutions are in complete agreement with the assigned X-ray geometry around the M(II) centers. The complexes show weak antiferromagnetic coupling with ∣J∣ = 1.8-4.2 cm−1 in the μ-1,3- bridged squarato compounds 1-3, and J = −16.1 cm−1 in the corresponding μ-1,2- bridged squarato complex 4. The magnetic properties are discussed in relation to the structural data. 相似文献
14.
Reaction of [NiCl2(dtbpe)] (dtbpe = 1,2-bis(di-tert-butylphosphino)ethane) with one equivalent of NaBArF4 (BArF4 = tetrakis[3,5-bis(trifluoromethyl)phenyl]borate) gives the dinuclear chloro-bridged nickel complex [Ni2(μ-Cl)2(dtbpe)2](BArF4)2 (1). [Ni(solv)6](BF4)2 reacts with dtbpe to give, depending on the solvent, the fluoro-bridged complex [Ni2(μ-F)2(dtbpe)2](BF4)2 (2) (solv = THF) or the mononuclear chelate complex [Ni(MeCN)2(dtbpe)](BF4)2 (3) (solv = MeCN). In 1-3, nickel cations are coordinated in a square-planar fashion according to X-ray crystallography. No Ni-Ni interaction was observed in dinuclear halogen-bridged complexes 1 and 2. 相似文献
15.
Two iron(III) complexes, [Fe4OCl(O2CMe)3(O3PC6H9)3(py)5] (1) and [Fe7O2(O2CPh)9(O3PC6H9)4(py)6] (2), have been prepared through solution reactions of [Fe3O(O2CR)6(H2O)3]Cl (R = Me, Ph) with cyclohexenephosphonic acid. Both compounds contain triangular oxo-centered [Fe3(μ3-O)]7+ units. In complex 1, the fourth iron atom is capped on this triangular unit through O-P-O bridges, forming a tetranuclear cluster with a tetrahedral arrangement of iron atoms. In complex 2, two equivalent [Fe3(μ3-O)]7+ units are connected by the fourth iron atom through four phosphonate ligands, forming a heptanuclear cluster. Variable temperature susceptibility measurements were performed for 1 and 2. Both exhibit dominant antiferromagnetic interactions between the Fe(III) centers. 相似文献
16.
Three new o-thioetherphenol ligands have been synthesized: 1,2-bis(3,5-di-tert-butyl-2-hydroxyphenylsulfanyl)ethane (H2bse), 1,2-bis(3,5-di-tert-butyl-2-hydroxyphenylsulfanyl)benzene (H2bsb), and 4,6-di-tert-butyl-2-phenylsulfanylphenol (Hpsp). Their complexes with copper(II) were prepared and investigated by UV-Vis-, EPR-spectroscopy; their electro- and magnetochemistry have also been studied: [CuII(psp)2] (1), [CuII2(bse)2] (2), [CuII2(bsb)2] (3), [CuII(bsb)(py)2] (4). The crystal structures of the ligands H2bse, H2bsb, Hpsp and of the complexes 1, 2, 3, 4 have been determined by X-ray crystallography. 相似文献
17.
Zhi-Guo Gu You Song Cheng-Hui Li Yi-Zhi Li Xiao-Zeng You 《Inorganica chimica acta》2005,358(13):4057-4061
A new tri-cyanometalate building block for heterometallic complexes, [PPh4]2[FeII(Tpms)(CN)3] (2) (PPh4 = tetraphenylphosphonium; Tpms = tris(pyrazolyl) methanesulfonate), has been prepared. Using it as a building block, a one-dimensional chain compound, {[FeII(Tpms)(CN)3][MnII(H2O)2( DMF)2]} · DMF (3), has been synthesized and structurally characterized. The magnetic properties of 3 correspond to a ferromagnetic chain with weak long-range superexchanged magnetic interaction between the high-spin manganese(II) ions. 相似文献
18.
Wolfgang Bauer 《Inorganica chimica acta》2009,362(7):2341-2346
Five new octahedral iron(II) complexes [FeL2(4-dpa)]n(EtOH) (1), [FeL2(bipy)]n(DMF) (2), [FeL1(bpee)]n (3), [Fe2L3(1-meim)4](1-meim)4 (4) and [FeL1(DMAP)2] (5), with L1 and L2 being tetradentate coordinating Schiff base like ligands (L1 = (E,E)-[{diethyl-2,2′-[1,2-phenylenebis(iminomethylidyne)]bis[3-oxobutanato](2-)-N,N′,O3,O3′}, L2 = (3,3′)-[{1,2-phenylenebis(iminomethylidyne)]bis(2,4-pentane-dionato)(2-)-N,N′,O2,O2′}) and L3 being a octadentate dinucleating coordinating Schiff base like ligand ({tetraethyl-(E,E,E,E)-2,2′,2′′,2′′′-[1,2,4,5-phenylentetra(iminomethylidine)]tetra[3-oxobutanoato](2-)-N,N′,N′′,N′′′,O3,O3′,O3′′,O3′′′}); 4-dpa = di(4-picolyl)-amine, bipy = 4,4′-bipyridine, bpee = trans-1,2-bis(4-pyridyl)ethylene, 1-meim = 1-methylimidazole and DMAP = 4-dimethylaminopyridine, have been synthesized and characterised using X-ray structure analysis and T-dependent susceptibility measurements. Both methods indicate that all iron(II) centres are in the paramagnetic high-spin state over the whole temperature range investigated. The O-Fe-O angle, the so called bit of the equatorial ligand, is with an average of 111° in the region typical for high-spin iron(II) complexes of this ligand type. In the case of compound 1 an infinite two-dimensional hydrogen bond network can be found, for the compounds 2-4 no hydrogen bond interactions are observed between the complex molecules. A comparison of the curve progression obtained from the magnetic measurements of the mononuclear complex 5 and the polymeric complexes 1-3 leads to the conclusion that no magnetic interactions are mediated over the bridging axial ligands. For the dinuclear complex 4 weak antiferromagnetic interactions between the two iron centres are found. 相似文献
19.
To model the mononuclear FeIII-OOH species identified in the catalytic cycle of the anticancer drug bleomycin, the iron chemistry of the pentadentate ligand N-[bis(2-pyridylmethyl)aminoethyl]pyridine-2-carboxamide (H-PaPy3) has been investigated. The complex [FeIII(PaPy3)OCH3](ClO4) was reacted with H2O2 to form a red species (max=480 nm, =1800 M–1 cm–1) with an S=1/2 EPR signal at g=2.25, 2.17, and 1.95. This species has been identified by electrospray ionization mass spectrometry as [FeIII(PaPy3)OOH](ClO4) and further characterized by resonance Raman and EXAFS analysis. The decomposition of this intermediate leads to the modification of the ligand, as revealed by 1H NMR. One hydrogen atom is substituted by a solvent-derived methoxy group. The substitution at this site is a result of the two-electron oxidation of the ligand following the heterolytic cleavage of the O–O bond of the FeIII-OOH species. This is a plausible mechanism to rationalize related ligand modifications that have been proposed in the decay of activated bleomycin.Abbreviations ABLM
activated bleomycin
- BLM
bleomycin
- ESI-MS
electrospray ionization mass spectrometry
- EXAFS
extended X-ray absorption fine structure
- H-PaPy3
N-[bis(2-pyridylmethyl)aminoethyl]pyridine-2-carboxamide 相似文献
20.
Hybrid scorpionate/cyclopentadienyl titanium and zirconium complexes with alkoxide and imido ligands
Antonio Otero Juan Fernández-Baeza Antonio Antiñolo Agustín Lara-Sánchez Margarita Sánchez-Molina Manuel Urbano-Cuadrado 《Inorganica chimica acta》2009,362(8):2909-2789
The reactivity of hybrid scorpionate/cyclopentadienyl ligand-containing trichloride zirconium complexes [ZrCl3(bpzcp)] (1) [bpzcp = 2,2-bis(3,5-dimethylpyrazol-1-yl)-1,1-diphenylethylcyclopentadienyl] and [ZrCl3(bpztcp)] (2) [bpztcp = 2,2-bis(3,5-dimethylpyrazol-1-yl)-1-tert-butylethylcyclopentadienyl] toward several lithium alkoxides has been carried out. Thus, alkoxide-containing complexes [ZrCl2(OR)(bpzcp)] (R = Me, 3; Et, 4; iPr, 5; (R)-2-Bu, 6), [ZrCl2(OR)(bpztcp)] (R = Me, 7; Et, 8; iPr, 9; (R)-2-Bu, 10) and [Zr(OR)3(bpztcp)] (R = Et, 11; iPr, 12) were prepared by deprotonation of the appropriate alcohol group with BunLi followed by reaction with 1 or 2. In addition, the imido-complex [Ti(NtBu)Cl(bpztcp)(py)] (13) were also prepared. The structures of these complexes have been proposed on basis of spectroscopic and DFT methods. 相似文献