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1.
The antiradical activity of the functionalized triphenylantimony(V) catecholates Ph3Sb[4-O(CH2CH2)2N-3,6-DBCat] (I), Ph3Sb[4,5-Piperaz-3,6-DBCat] (II), and Ph3Sb[4-PhN(CH2CH2)2N-3,6-DBCat] (III) (where [4-O(CH2CH2)2N-3,6-DBCat]2?, [4,5-Piperaz-3,6-DBCat]2?, and [4-PhN(CH2CH2)2N-3,6-DBCat]2? are the dianionic ligands 3,6-di-tert-butyl-4-(morpholin-1-yl)-, 3,6-di-tert-butyl-4,5-(piperazine-1,4-diyl)-, and 3,6-di-tert-butyl-4-(4-phenylpiperazin-1-yl)catecholates, respectively) was studied in reactions with the diphenylpicrylhydrazyl radical during autooxidation of unsaturated fatty (oleic and linoleic) acids with lipid peroxidation of Russian sturgeon (Acipenser gueldenstaedti B.) sperm and human blood erythrocytes in vitro as examples. The EC50 and n DPPH values obtained indicate the high antiradical activity of complexes II and III in the reactions with the stable radical. On the whole, complexes I–III inhibit the lipid peroxidation in both model (oxidation of unsaturated fatty acids) and in vitro experiments. The inhibiting effects of the complexes are comparable with and even, in some cases, higher than those of the known antioxidant ionol.  相似文献   

2.
The products of UV photolysis of ternary Ar?CH4(CD4)?F2 mixtures (1:c:c 0,c, c 0=0.001–0.01) at 13–16 K were identified by ESR and FTIR spectroscopy. These products are?CH3 (?CD3) radicals of typesI andII and molecular CH3F?HF complexes. The latter were characterized by the IR bands of the stretching C?F (1003 cm?1) and H?F (3774 cm?1) vibrations. The ESR spectra of radicalsI are asymmetric. The anisotropy of theg-factor (Δg~10?3) of radicalI indicates that the structure of the radicals is nonplanar. The ESR spectrum of the typeII radical is identical to that of matrix-isolated?CH3 (?CD3) radicals with the planar structure (Δg<5·10?5). Under the experimental conditions, the amount of complexes formed in the photolysis is equal to 0.022·c. When the photolysis is ceased, radicalI disappears after ≈103 s and radicalII is stabilized. The limiting concentrations of the stabilized?CH3 and?CD3 radicals are equal to 2·10?2·c and 2·10?3·c, respectively. A mechanism of the formation of the products is suggested. It is based on the assumption that both matrix-isolated CH4 and F2 and their heterodimers CH4?F2 are present in the samples and it takes into account the long-range migration of translationally excited flourine atoms. The CH3F?HF complexes and radicalsI are generated by the photolysis of the CH4?F2 heterodimers. The decay of radicalsI is caused by geminate recombination of proximate F...CH3 pairs. RadicalsII are formed in the reaction of translationally excited fluorine atoms with isolated CH4 (CD4) molecules.  相似文献   

3.
A series of new tin(IV) complexes based on 2-hydroxy-3,6-di-tert-butyl-para-benzoquinone (LH) of the general formula L2SnR2 (R = Me (I), Et (II), Bu n (III), Ph (IV)) and LSnMe3 (V) were synthesized. The obtained compounds were characterized by IR and 1H, 13C and 119Sn NMR spectroscopy and elemental analysis. The X-ray diffraction analysis was carried out for complexes L2Sn(Bu n )2 (III) and LSnMe3 (V). The low-frequency region of the IR spectra, which has not earlier been studied in detail, was interpreted for compounds I–V and previously described complex LSnPh3 (VI). The electrochemical properties of LH and related tin complexes I–VI were studied. The nature of the hydrocarbon groups at the metal atom affects the stability of the intermediates formed in the electrochemical reactions.  相似文献   

4.
[Ph3PhCH2P]+[PdCl3(DMSO)]? · DMSO (I), [Ph4P]+[PdCl3(DMSO)]? (II), and [Ph4Sb(DMSO)]+[PdCl3(DMSO)]? (III) complexes have been synthesized via the reaction of palladium chloride with equimolar amounts of triphenylbenzylphosphonium chloride, tetraphenylphosphonium chloride, and tetraphenylstibonium chloride, respectively. According to X-ray diffraction data, the cations of complexes I (CPC = 104.90(8)°–111.61(9)°) and II (CPC = 105.12(10)°–111.46(10)°) have slightly distorted tetrahedral structures with P-C bond lengths of 1.786(2)–1.809(2) and 1.791(2)–1.799(2) Å, respectively. The antimony atom in the [Ph4Sb(DMSO)]+ cation has a trigonal bipyramidal surrounding with the dimethyl sulfoxide (DMSO) oxygen atom in an axial position (Sb...O 2.567(2) Å). The palladium atoms in the square mononuclear anions of complexes I, II, and III are tetracoordinate, and Pd-Cl distances are 2.3101(5)–2.3104(5) Å, 2.2950(7)–2.2038(7) Å, and 2.2986(9)–2.3073(9) Å, respectively. The DMSO ligands are coordinated to the palladium atom through the sulfur atom (Pd-S, 2.2318(5) (I), 2.2383(6) (II), and 2.2410(9) Å (III)).  相似文献   

5.
The unimolecular dissociation of (CH3)2C+OC2H5 ions (I) and their deuterated analogs, generated by ion-molecule reactions (IMR) in acetone-ethyl iodide mixtures was studied by tandem mass Spectrometry methods. Two significant processes that yielded I ions were identified. The Fourier transform ion cyclotron resonance study showed that the reaction between ionized ethyl iodide and neutral acetone was the principal source of I. This process involved the formation of the stable mixed ionized dimer, [C2H5I·O=C(CH3)2] (II), which dissociated by the loss of an I atom. Other important fragmentation pathways of II were the formation of C2H5I, (CH3)2CO; and (CH3)2COI+ and the loss of CH3CHI·. The major dissociation of I was the loss of C2H4. The activation energy for this reaction was determined by metastable ion appearance energy measurements to be ~55 kJ mol?1 above the thermochemical minimum. The analysis of the metastable and collision-induced dissociation of D-labeled I showed an unusual time-energy effect on the degree of H/D mixing, with the highest selectivity for the ethene loss [β-H(D)-atom shift] being observed for ions with the lowest internal energies. Collisional excitation could not produce significant H/D mixing among dissociating ions. The results were rationalized by the existence of two species— the classical (2-ethoxypropyl) and nonclassical (proton-bound acetone-ethene pair) isomers of I. The classical structure was originally formed by IMR or from II. The energy barrier for the classical to nonclassical isomerization lay well above the thermochemical threshold for C2H4 loss, providing only limited H-atom mixing in nonclassical ions that were always formed in their dissociative state. The effect of the proton affinity of the carbonyl compound on the H/D mixing in RR′C+OC2H5 ions was studied. It was shown that the selectivity for the ethene loss (β-H-atom shift) generally increased with the increase of the proton affinity of RR′CO. Neutralization-reionization mass spectrometry was applied to a study of (CH3)2C+OR ions, where R = H, I, C2H5. The observation of a recovery signal for the ion I was attributed to the formation of the 2-ethoxypropyl radical. Neutral counterparts of (CH3)2COI+ ions were also generated, being the first example of IO-substituted alkyl radicals.  相似文献   

6.
Interfacial distribution of trace amounts of ReO 4 ? ions between aqueous solutions of mineral acids and solutions of diphosphoryl-substituted aza podand [Ph2P(O)CH2CH2OCH2CH2]2NBu (I) in dichloroethane was studied. The stoichiometry of extracted complexes was determined, the influence of HClO4, HNO3, HCl, and H2SO4 concentration in aqueous phase and the nature of organic solvent on the efficiency of transition of ReO 4 ? ions into organic phase was considered. Aza podand I shows larger extraction ability toward Re(VII) than monophosphorylated amines. The possibility of selective extraction and preconcentration of ReO 4 ? ions by a complex-forming sorbent obtained by the noncovalent binding of compound I on the surface of carbon nanotubes was shown.  相似文献   

7.
李悦生 《高分子科学》2013,31(4):574-582
The ethylene/cyclopentadiene (CPD) copolymerization behavior by using fluoro-substituted bis(β-enaminoketonato) titanium complexes [FC6H4NC(CH3)CHCO(CF3)]2TiCl2 (1a1c) has been investigated in detail. Upon utilizing MMAO as a cocatalyst, complexes 1a1c exhibit high catalytic activities, affording the copolymers with high molecular weight and unimodal molecular weight distribution. Compared with non-substituted complex [C6H5NC(CH3)CHCO(CF3)]2TiCl2 (1), complexes 1a1c can produce the copolymers with CPD incorporation adjusted in a wide range due to the enhancement of electrophilicity of metal center caused by introducing electron-withdrawing groups. Especially complex 1c bearing fluorine at the para-position of N-aryl moiety provides the highest CPD incorporation, which is nearly two times (18.5 mol%) higher than the non-substituted complex 1 (8.9 mol%) under the same conditions. The highest CPD incorporation up to 24.6 mol% can be easily achieved using this complex. 1H- and 13C-NMR spectra demonstrate that these fluoro-substituted complexes possess regioselective nature with exclusive 1,2-insertion fashion, and alternating ethylene-CPD sequence can be detected at high CPD incorporation.  相似文献   

8.
Charge-transfer complexation of iodine with a new benzo-substituted macrocyclic diamide 5,6,7,8,9,10-hexahydro-2H-1,13,4,7,10-benzodioxatriazacyclopentadecine-3,11(4H,12H)-dione (L) with iodine was studied spectrophotometrically in chloroform, dichloromethane and their 1:1 (v/v) mixture. The observed time dependence of the charge-transfer band and subsequent formation of I3 - ion are related to the slow formation of the initially formed 1:1 L.I2 outer complex to an inner electron donor-acceptor (EDA) complex, followed by fast reaction of the inner complex with iodine to form a triiodide ion, as follows: L + I2L.I2 (outer complex), fast L.I2 (outer complex) → (L.I+)I- (inner complex), slow (L.I+)I- (inner complex) + I2 → (L.I+)I3 -, fast The pseudo-first-order rate constants for the transformation process were evaluated in different solvent systems. The stability constants of the resulting EDAr complexes were also evaluated and the solvent effect on their stability is discussed. The resulting complexes were isolated and characterized by FTIR and 1H NMR spectroscopy.  相似文献   

9.
As the active site model of [FeFe]-hydrogenases, complexes [(μ-PDT)Fe2(CO)5]2(dppb) (PDT = SCH2CH2CH2S, dppb = Ph2PCH2CH2CH2CH2PPh2) (1) and [(μ-SCH2)2NCH2CO2Me]Fe2(CO)5(dppm) (dppm = Ph2PCH2PPh2) (2) were prepared by reactions of (μ-PDT)Fe2(CO)6 (A) or [(μ-SCH2)2NCH2CO2Me]Fe2(CO)6 (B) with dppb or dppm in the presence of the decarbonylating agent Me3NO?2H2O in MeCN at room temperature. Complex 1 was characterized by elemental analysis, IR, and 1H (31P, 13C) NMR spectroscopic techniques. In addition, the molecular structures of 1 and 2 have been confirmed by single crystal X-ray diffraction analysis. In the crystal structure of 1, two phosphorus atoms of dppb reside in a basal position of the square-pyramidal coordination sphere of the Fe2 and Fe3 atoms. However, in the crystal structure of 2, P1 atom of dppm resides in an apical position of the square-pyramidal coordination sphere of the Fe2 atom.  相似文献   

10.
A number of stannylene complexes with different M: Sn ratios were obtained using various metals and substituents at the tin atom. The structures of the complexes were examined. A reaction of CpMn(CO)2THF with (Ph4As)+(SnCl3)? gave the ionic complex [Ph4As]+[CpMn(CO)2SnCl3]? (I). The action of C6F5MgBr on the complex C5H5Mn(CO)(NO)SnCl3 produced C5H5Mn(CO)(NO)Sn(C6F5)3 (II). Replacement of the Cl ions in the complex [CpFe(CO)2]2SnCl2 by phenylacetylenide groups gave rise to the neutral complex [CpFe(CO)2]2Sn(C≡CPh)2 (III). A reaction of (Dppm)PtCl2 (Dppm is 1,1-bis(diphenylphosphino)methane) with SnCl2 · 2H2O in the presence of diglyme yielded the ionic complex [η3-CH3O(CH2)2O(CH2)2OCH3)SnCl]+[(η 2-Dppm)Pt(SnCl3)3]? (IV). Transmetalation in a reaction of [(Dppe)2CoCl][SnCl3] · PhBr (Dppe is 1,2-bis(diphenylphosphino)ethane) with (Dcpd)PtCl2 (Dcpd is dicyclopentadiene) in the presence of SnCl2 afforded the ionic complex [Pt(Dppe)2]3[Pt(SnCl3)5]2 (V). Structures I–V were identified by X-ray diffraction. In these structures, the formally single bonds between the atoms of transition metals M (Mn, Fe, and Pt) and Main Group heavy elements (Sn and P) having vacant d orbitals are appreciably shortened. The M-Sn bond length in complexes II and III are virtually independent of the substituents at the tin atom and the Pt-Sn bond length in complexes IV and V is virtually independent of the Pt: Sn ratio.  相似文献   

11.
Complexes [Ph3MeP] 2 + [BiI3.5Br1.5(C5H5N)]2? · C5H5N(I), [Ph4Bi] 4 + [Bi4I16]4? · 2Me2C=O (II), and [Ph3(iso-Am)P] 4 + [Bi8I28]4? · 2Me2C=O (III) were synthesized by reactions of bismuth iodide with triphenylmethylphosphonium bromide, triphenylbismuthonium sulfosalicylate, and triphenylisoamylphosphonium iodide, respectively. The crystal structures of complexes I–III were determined by X-ray crystallography. The complexes contain, in addition to cations and solvent molecules, mono-, tetra-, and octanuclear anions, in which bismuth atoms are in octahedral coordination.  相似文献   

12.
The reaction of pentaphenylantimony with mercury iodide affords the ionic complex [Ph4Sb] 2 + [Hg2I6]2?·Ph2Hg (I). The [Ph4Sb] 2 + [Hg2I6]2? (II) and [Ph4Sb] 2 + [Cd2I6]2? (III) complexes are synthesized from tetraphenylantimony iodide and mercury and cadmium iodides. The [Ph4Sb] 2 + [Hg4I10]2? complex (IV) is prepared from tetraphenylantimony 2,4-dimethylbenzenesulfonate and mercury iodide. According to the X-ray diffraction data, the Sb atom in the [Ph4Sb]+ cations of complex I has virtually ideal tetrahedral coordination (the CSbC angles are 108.09°–109.64°). In the central square fragment Hg2I2 of the [Hg2I6]2? anion, the Hg-Ibr bond lengths are 2.825 and 3.075 Å, and the terminal iodine atoms are more strongly bonded to the mercury atoms (Hg-Iterm 2.691 and 2.700 Å). The [Cd2I6]2? anion in complex III has a similar structure (the Cd-Ibridg and Cd-Iterm distances are 2.865, 2.872 and 2.723, 2.748 Å, respectively). The anions in complex IV are joined by I…Hg (3.651 Å) and I…I (4.058 Å) interactions into an infinite dimeric network.  相似文献   

13.
Three new complexes, [CdL2(CH3COO)2(H2O)2] (I), CdL2Br2 (II), CdL2I2 (III), have been successfully synthesized by self-assembly of corresponding metal salts with (E)-2-(3-(4-(1H-imidazole-1-yl)styryl)-5,5-dimethylcyclohex-2-enylidene)malononitrile (L). The structures of the complexes were determined by single crystal X-ray diffraction analysis (CIF file CCDC nos. 957831 (I), 957792 (II), 957832 (III)). In complex I, central metal is six-coordinated and the crystal packing shows a 3D supramolecular framework. Complexes II and III display the similar 2D supramolecular structures in which the central metals are four-coordination. The luminescent properties were investigated.  相似文献   

14.
The reaction between ClCH2-R-CH2Cl, R = p-C6H4, and [Ph3Sn]Li+ yields Ph3Sn-CH2-R-CH2-SnPh3 (1) in high yield. The related known compound R = CH2CH2 (1a) is synthesized by the reaction of the di-Grignard reagent BrMg(CH2)4MgBr with two equivalents of Ph3SnCl. Cleavage of a single Sn-Ph group at each tin centre of both compounds using HCl/Et2O yields the corresponding bis-chlorostannanes Ph2ClSn-CH2-R-CH2-SnClPh2, R = (CH2)4 (2) and R = C6H4 (3), respectively. Compounds 1, 2 and 3 are crystalline solid materials and their single crystal X-ray structures are reported. In the solid state both 2 and 3 form self-assembled ladder structures involving alternating intermolecular Cl-Sn?Cl and Cl?Sn-Cl bonded chains at both ends of the distannanes with 5-coordinate tin atoms. Recrystallization of 3 from CH2Cl2 in the presence of DMF yields the bis-DMF adduct (4) in which no self-assembled structures were noted. Evaluation of the chlorostannanes 2 and 3 against a suite of bacteria, Staphylococcus aureus, Escherichia coli and Photobacterium phosphoreum is reported and compared to the related mono-chlorostannanes Ph2(CH3)SnCl and Ph2(PhCH2)SnCl.  相似文献   

15.
A series of ligands, (Ph2PCH2)2NR (R = -CH3) (1), -C(CH3)3, (2) -m-C6H4SO3Na (3), and their Pd(II) complexes have been synthesized under nitrogen atmosphere using Schlenk method. All compounds were characterized using elemental analysis and spectroscopic techniques (AAS, NMR (1H, 31P)). Based on the analysis the complexes have been proposed as in square planar geometry. The Pd(II) complexes were applied to the Heck reaction of aryl halide (Br, Cl) with methyl acrylate. The results have exhibited that complexes [PdCl2((Ph2PCH2)2NCH3)] (4) and [PdCl2((Ph2PCH2)2NC(CH3)3)] (5) have shown higher turnover numbers (TON) than complex [PdCl2(Ph2PCH2)2N-m-C6H4SO3Na] (6).  相似文献   

16.
Neutral complex 1 and mono-cationic complex 2 were made available using Ph2PCH2CH2OCH3 and 1,2-diphenyl-1,2-ethanediamine ligands. One of the chloride atoms in complex 1 was abstracted by AgOTf to prepare the mono-cationic O–Ru–P closed complex 2. The hemilability of hybrid ether-phosphine ligand in such complexes was monitored by 31P{1H} NMR and confirmed by X-ray single crystal. XRD structure of complex 2 was found to be a Trigonal crystal system with P3 space group and Z = 6.  相似文献   

17.
A prolonged storage of a solution of RhCl3·nH2O in N,N-dimethylformamide (DMF) at room temperature is attended by the consecutive formation of two precipitates, which mainly contain the [(CH3)2NH2][RhCl5(DMF)] complex (I) and the complex [RhCl3(DMF)3] (II) liberates. The addition of PPh4Cl to an aqueous solution of complex I brings about the precipitation of [PPh4][RhCl4(H2O)2] (III). Complex II (a mixture of mer-and fac-isomers) can be obtained also by treatment of [RhCl3(CH3CN)3] with DMF. In the course of the latter reaction, the formation of intermediate complex [RhCl3(CH3CN)2(DMF)] (IV) is observed. Complexes I–IV are characterized by elemental analysis; complexes I, II, and IV are characterized by the IR and 1H and 13C NMR spectra. The structures of III and IV are determined by X-ray diffraction analysis.  相似文献   

18.
Platinum(II) cyclo-hexamethylenedithiocarbamate (HmDtc) complex, [Pt{S2CN(CH2)6}2] (I), and its solvated form, Pt{S2CN(CH2)6}2] · CHCl3 (II), are synthesized and characterized by the 13C MAS NMR data. The HmDtc ligands in structure I are not equivalent, whereas the solvation of the complex is accompanied by the structural unification of the initially nonequivalent HmDtc ligands. In addition, the spectra are characterized by the 13C-195Pt spin-spin coupling. The noncentrosymmetric molecular structure of compound I determined by X-ray diffraction analysis includes two nonequivalent dithiocarbamate ligands coordinated by the metal in the S,S′-bidentate mode. The central atom forming the [PtS4] chromophore (intraorbital dsp 2-hybrid state of platinum) shifts from the plane of four sulfur atoms by 0.07 Å in the vertex of the flattened tetragonal pyramid. The seven-membered heterocycles ?N(CH2)6 of the HmDtc ligands are oppositely directed in space relative to the [S4] plane (trans orientation). The thermal behavior of compounds I and II are studied by simultaneous thermal analysis. In both cases, the final product of the multistage thermal destruction of the complexes is reduced metallic platinum.  相似文献   

19.
Heterometallic complexes with pyridine-N-oxide (PyO), Ru(NO)(NO2)4(OH)Ni(PyO)2(H2O)] · CH3COCH3 (I), [{Ru(NO)(NO2)2(μ-NO2)2(μ-OH)Co}2(μ-PyO)] · H2O · CH3COCH (II), and [Ru(NO)(NO2)4(OH)Cu(PyO)2 (III), are isolated in the reactions of Na2[Ru(NO)(NO2)4(OH)] with nitrates of the corresponding metals in the presence of the organic ligand. The compounds synthesized are characterized by IR spectra, thermal analysis, and X-ray diffraction analysis. Depending on the M2+ cation, the ruthenium cation is coordinated through the bidentate (III, Cu2+) or tridentate (I, Ni2+ and II, CO2+) mode involving the bridging OH group and one or two NO2 groups. The thermal decomposition of complex II results in the formation of a Co0.5Ru0.5 solid solution, which is thermodynamically stable under the decomposition conditions. The thermolysis of complexes I and III in a hydrogen atmosphere leads to the formation of metastable solid solutions.  相似文献   

20.
The substitution of a labile THF ligand in Cr(CO)5(THF) by the Ph2Se2 molecule provided the monomeric complex Cr(CO)5(Ph2Se2) (I). The similar diiodo-tricarbonyl-iron complex (CO)3FeI2(Ph2Se2) (II) (along with [(CO)3Fe(??-SePh)3Fe(CO)3]+(I5)? (III) as a by-product) was separated upon the treatment of ??phenylselenyl iodide?? [PhSeI] with iron pentacarbonyl, Fe(CO)5. Complex II is isostructural with the known tellurium-containing analogue, (CO)3FeI2(Te2Ph2). The latter have provided the dimeric tellurophenyl bridged iodo-tricarbonyl-iron complex [(CO)3IFe(??-TePh)]2 (IV) under action of the excess of Fe(CO)5. Its bromide analogue [(CO)3BrFe(??-TePh)]2 (V) was prepared upon the treatment of PhTeBr with the excess of Fe(CO)5. The reaction of [PhSeI] with Re(CO)5Cl afforded only [(CO)6Re2(??-I)2(??-Se2Ph2)] (VI) in contrast to the (CO)3Re(PhTeI)3(??3-I) formation in similar known reaction of [PhTeI]. The molecular and crystal structures of I?CVI is discussed.  相似文献   

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