首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
In this report the affinity of four N4-tetradentate ligands that incorporate the 2-methylpyridyl functionality with hexavalent actinides $(\mathrm{AnO}_{2}^{2+})$ has been investigated in methanol solution. The ligands studied include N,N??-bis(2-methylpyridyl)diaminoethane (BPMDAE), N,N??-bis(2-methylpyridyl)-1,3-diaminopropane (BPMDAP), N,N??-bis(2-pyridylmethyl)piperazine (BPMPIP), and trans-N,N-bis(2-pyridylmethyl)-1,2-diaminocyclohexane (BPMDAC). Conditional stability constants describing the strength of the interaction were determined by UV?Cvisible spectrophotometry. The log10 K 101 values for both U(VI) and Pu(VI) are comparable and show the same trend of stability with ligand structure. Dinuclear complexes are also indicated as being important. The log10 K 201 values for Pu(VI) complexation with the N4-ligands are identical for the four ligands (within experimental error), indicating that the structure of the ligand backbone has little effect on the stability of the (PuO2)2L2+ complex. The exception to this trend is the behavior of N,N??-bis(2-pyridylmethyl)piperazine (BPMPIP) with Pu(VI). This ligand displays a tendency to reduce Pu(VI) within the experimental time frame of 45 minutes. BPMPIP is the only ligand tested that contains tertiary amines in the ligand backbone. The decomposition of BPMPIP by Pu(VI) suggests a susceptibility of tertiary amines to oxidative degradation.  相似文献   

2.
Microwave-assisted synthesis of the ligands N,N-bis-(2-pyridylmethyl)amine (BMPA), N-(methylpropanoate)-N,N-bis-(2-pyridylmethyl)amine (MPBMPA), N-(propanamide)-N,N-bis-(2-pyridylmethyl)amine (PABMPA), PNBMPA (N-(3-propionitrile)-N,N-bis-(2-pyridylmethyl)amine), N-(3-aminopropyl)-N,N-bis-(2-pyridylmethyl)amine (APBMPA), and lithium N-(proponoate)-N,N-bis-(2-pyridylmethyl)amine (LiPBMPA) are reported. High yields and short reaction time were obtained for condensation and Michael addition.  相似文献   

3.
《中国化学快报》2022,33(7):3439-3443
A process for actinide(III) and lanthanum(III) extraction separation from high-level liquid waste (HLLW) was proposed, with N,N,N',N'-tetraoctyl diglycolamide (TODGA) as the extractant, tri-n?butyl phosphate (TBP) as the phase modifier and 2,6-bis[1-(propan-1-ol)-1,2,3-triazol-4-yl]pyridine (PyTri-Diol or PTD) as hydrophilic stripping agent. This ‘hot test’ was successfully carried out, achieving 99.92% removal of americium-241 (241Am) with a separation factor SF(Eu/Am) of 3.8 × 103 in the actinide(III) product solution. The results show that bisamide podand extractants can effectively realize the extraction and separation of actinide(III) and lanthanum(III) from Chinese commercial HLLW and thus have a bright practical application potential for the treatment of commercial HLLW.  相似文献   

4.
Reactions of (1R,2R)-N1,N2-bis(pyridinylmethyl)cyclohexane-1,2-diamine derivatives, (1R,2R)-2-bpcd and (1R,2R)-3-bpcd [(1R,2R)-2-bpcd = (1R,2R)-N1,N2-bis(pyridin-2-ylmethyl)cyclohexane-1,2-diamine, (1R,2R)-3-bpcd = (1R,2R)-N1,N2-bis(pyridin-3-ylmethyl)cyclohexane-1,2-diamine], with CdI2 in an analogous way led to the formation of a chiral discrete mononuclear complex and a chiral one-dimensional polymeric chain, respectively, which may be attributed to the positional isomerism of the ligands. The chiral organic ligands and complexes display luminescent properties indicating that they may have a potential application as optical materials. Powder second-harmonic generation (SHG) efficiency measurement shows that the SHG efficiency of the complexes is approximately 0.3 and 0.45 times that of KDP, respectively.  相似文献   

5.
Five mononuclear complexes of manganese(II) of a group of the general formula, [MnL(NCS)2] where the Schiff base L = N,N′-bis[(pyridin-2-yl)ethylidene]ethane-1,2-diamine (L1), (1); N,N′-bis[(pyridin-2-yl)benzylidene]ethane-1,2-diamine (L2), (2); N,N′-bis[(pyridin-2-yl)methylidene]propane-1,2-diamine (L3), (3); N,N′-bis[(pyridin-2-yl)ethylidene]propane-1,2-diamine (L4), (4) and N,N′-bis[(pyridin-2-yl)benzylidene]propane-1,2-diamine (L5), (5) have been prepared. The syntheses have been achieved by reacting manganese chloride with the corresponding tetradentate Schiff bases in presence of thiocyanate in the molar ratio of 1:1:2. The complexes have been characterized by IR spectroscopy, elemental analysis and other physicochemical studies, including crystal structure determination of 1, 2 and 4. Structural studies reveal that the complexes 1, 2 and 4 adopt highly distorted octahedral geometry. The antibacterial activity of all the complexes and their respective Schiff bases has been tested against Gram(+) and Gram(−) bacteria.  相似文献   

6.
In this study the separation of Am(III) from Eu(III) in nitric acid using two BTP-type N-donor ligands, 2,6-bis(6-ethyl-1,2–diazine-3-yl)pyridine (Et-BDP) and 2,6-bis(4-npropyl-2,3,5,6-tetrazine-1-yl)pyridine (nPr-tetrazine) is presented. The extraction and separation properties of both ligands are tested by two phase liquid-liquid extraction at different acid concentrations. In contrast to nPr-BTP the bisdiazinyl ligand Et-BDP is prone to protonation at nitric acid concentrations of 0.2 M and higher. A separation factor of SFAm/Eu ≈ 5 is obtained using Et-BDP as extracting ligand and with nPr-tetrazine a SFAm/Eu of 9.1 is realized. Hereby 2-bromodecanoic acid as lipophilic anion source is needed.  相似文献   

7.
Lithium-7 NMR spectroscopy was used to investigate the stoichiometry and stability of a Li+ complex with N1,N2-bis(pyridin-2-ylmethylene)ethane-1,2-diamine (L1), N1,N3-bis(pyridin-2-ylmethylene)propane-1,3-diamine (L2) and N1,N4-bis(pyridin-2-ylmethylene) butane-1,4-diamine (L3) in acetonitrile (AN) and nitromethane (NM) solutions. A competitive 7Li NMR method was also employed to probe the complexation of Mn2+, Cd2+ and Zn2+ ions with L1, L2 and L3 in the same solvents. The formation constants of the resulting complexes were evaluated from computer fitting of the mole ratio data to an equation that relates the observed chemical shifts to the formation constant. In both solvents, the stability of the resulting 1:1 complexes were found to vary in the order Zn2+>Cd2+>Mn2+>Li+. In addition, the stability of M–L complexes of M2+ with the Schiff base ligands found to vary in the order M2+–L1 > M2+–L2 > M2+–L3.  相似文献   

8.
Electrochemical copolymerizations of N1,N2-bis(thiophen-3-ylmethylene)benzene-1,2-diamine (TMBD), 4-methyl-N1,N2-bis (thiophen-3-ylmethylene)benzene-1,2-diamine (MTMBD) and 4-nitro-N1,N2-bis(thiophen-3-ylmethylene)benzene-1,2-diamine (NTMBD) with 3,4-ethylenedioxy thiophene (EDOT) were carried out in CH3CN/LiClO4 (0.1 M) solvent–electrolyte couple via potentiodynamic electrolysis. The resulting copolymers were characterized by cyclic voltammetry (CV), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The conductivity measurements of copolymers and PEDOT were carried out by the four-probe technique.  相似文献   

9.
o-Phenylenediamine reacts with 2-formyl-, 2-acetyl-, or 2-benzoylpyridine in ethanol in the presence of cobalt, nickel, copper, or zinc chlorides to form monomeric complexes ML1–3Cl2·nH2O {M = Co, Ni, Cu, Zn; L1 = N 1,N 2-bis(pyridin-2-ymethylidene)benzene-1,2-diamine, L2 = N 1,N 2-bis(pyridin-2-ylethylidene) benzene-1,2-diamine, L3 = N 1,N 2-bis[phenyl(pyridin-2-yl)methylidene]benzene-1,2-diamine; n = 0–3}. The condensation products (L1–L3) act in the complexes as tetradentate N,N,N,N-ligands. Thermolysis of the complexes occurs in two stages: dehydration (70–95°C) and complete degradation (320–450°C). At concentrations of 10?5–10?7 M, the complexes inhibit in vitro growth and proliferation of HL-60 human promyelocytic leukemia cells.  相似文献   

10.
New complexes [NiII(pbpaen)](ClO4)2 (1) and [CoIII(pbpaen)](ClO4)3 (2) (pbpaen = N′-(pyridin-2-ylmethyl)-N,N-bis {2-[(pyridin-2-ylmethyl)amino]ethyl}ethane-1,2-diamine) have been synthesized and characterized by IR and UV–Vis spectroscopies. An X-ray structure of the nickel(II) complex shows that [Ni(pbpaen)](ClO4)2 (1) crystallizes in the monoclinic space group P21/c. The cation [Ni(pbpaen)]2+ is pseudo-octahedral with one of the three pyridyl nitrogen atom uncoordinated. The crystal lattice of this complex is stabilized by intra and intermolecular hydrogen bonding systems, giving one-dimensional sheets like arrays. All attempts to obtain nickel or cobalt complexes with protonated forms of the ligand resulted in isolation of only [CoIII(bpaen)](ClO4)3 (3) compound in which the tripod pbpaen ligand has lost one of the three pyridylmethyl groups, procuring then bpaen ligand {bpaen = N,N-bis{2-[(pyridin-2-ylmethyl)amino]ethyl}ethane-1,2-diamine}. The X-ray crystal structure reveals that the compound 3 crystallizes in the orthorhombic space group Pna2 with the Co3+ ion having a distorted-octahedral environment. These two ligands with strong-field N donor stabilise the +3 oxidation state of the Co center.  相似文献   

11.
The N-donor complexing ligand 2,6-bis(5-(2,2-dimethylpropyl)-1H-pyrazol-3-yl)pyridine (C5-BPP) was synthesized and screened as an extracting agent selective for trivalent actinide cations over lanthanides. C5-BPP extracts Am(III) from up to 1 mol/L HNO(3) with a separation factor over Eu(III) of approximately 100. Due to its good performance as an extracting agent, the complexation of trivalent actinides and lanthanides with C5-BPP was studied. The solid-state compounds [Ln(C5-BPP)(NO(3))(3)(DMF)] (Ln = Sm(III), Eu(III)) were synthesized, fully characterized, and compared to the solution structure of the Am(III) 1:1 complex [Am(C5-BPP)(NO(3))(3)]. The high stability constant of log β(3) = 14.8 ± 0.4 determined for the Cm(III) 1:3 complex is in line with C5-BPP's high distribution ratios for Am(III) observed in extraction experiments.  相似文献   

12.
Two structurally similar centrosymmetric phenoxo-bridged dinuclear manganese(III) complexes, [Mn2(L1)2(N3)2] (1) and [Mn2(L2)2(NCS)2] (2), were prepared from the tetradentate bis-Schiff base ligands, N,N’-bis(salicylidene)propane-1,2-diamine (H2L1) and N,N’-bis(salicylidene)ethane-1,2-diamine (H2L2), respectively, in the presence of pseudohalides. The complexes have been characterized by FTIR, elemental analyses, and molar conductivity. Structures of the complexes have been confirmed by single-crystal X-ray determination. The bis-Schiff base ligands coordinate with Mn through their phenolate oxygen and imino nitrogen. Each Mn is an octahedral. The complexes showed that they exhibit high activity in catalytic olefin oxidation.  相似文献   

13.
A series of chromium(III)-, cobalt(III)-, and iron(III)-based complexes of the general formula [(NO)2MCl] (1–7) (NO: N-salicylidene(R)amine, R = 1-naphthyl or cyclohexyl) have been applied as catalysts for the coupling reaction of carbon dioxide and epoxystyrene (styrene oxide) in the presence of tetrabutylammonium bromide (Bu4NBr) as a cocatalyst. The reactions were carried out under relatively low pressure and solvent-free conditions. In addition, iron complexes (810) containing the ligands, N′-(thiophene-2-methylene)benzene-1,2-diamine, (8), N′-(quinoline-2-methylene)benzene-1,2-diamine (9), and sodium N-(4-sulfonato-salicylidene)-1,2-phenylenediamine (10) were also utilized for the catalytic reaction. The influence of metal center, ligand, temperature, and reaction time on the coupling reaction was investigated. The catalyst systems proved to be selective in the coupling reaction of CO2 and styrene oxide, resulting in cyclic styrene carbonate. In general, the iron(III)- and cobalt(III)-based catalysts bearing the aromatic 1-naphthyl terminal groups showed the highest catalytic activity under similar reaction conditions.  相似文献   

14.
The coordination complexes of trivalent f-element pertechnetates and perrhenates with some N-donor ligands were determined by using X-ray structural analysis: Nd3+ perrhenate with 2,6-bis(tetramethylfurano)-1,2,4-triazin-3-yl)-pyridine ([Nd(FBTP)3ReO4](ReO4)2 · 2H2O (I)), tris(2-pyridylmethyl)amine ([Nd(TPA)(ReO4)3] (II)) and N,N′-tetraethylmalonamide ([Nd(TEMA)4](ReO4)3 (III)). The coordination number of Nd is 10 in I, 9 in II and 8 in III. The complexes of Nd3+ pertechnetate and Am3+ pertechnetate with TPA have been also synthesized (Nd(TPA)(TcO4)3 (IV) and Am(TPA)(TcO4)3 (V)). The structure II does not change on replacement of perrhenate by pertechnetate and neodymium by americium.  相似文献   

15.
[M(EtBTP)3][BPh4]3 ⋅ 3 CH3CN (M=Nd, Am; EtBTP=2,6-bis(5,6-diethyl-1,2,4-triazin-3-yl)pyridine) have been synthesized from reactions of MCl3n H2O with EtBTP in acetonitrile followed by anion metathesis. Structural analysis reveals that these compounds contain M3+ cations bound by tridentate EtBTP ligands to create a tricapped trigonal prismatic geometry around the metal centers. Collection of high-resolution, single-crystal X-ray diffraction data also allowed reduction in bond lengths esd's, such that a slight contraction of Δ=0.0158(18) Å in the Am−N versus Nd−N bond lengths was observed, even though these cations ostensibly have matching ionic radii. Theoretical evaluation revealed enhanced metal–ligand bonding through back donation in the [Am(EtBTP)3]3+ complex that is absent in [Nd(EtBTP)3]3+.  相似文献   

16.
Reactions of 2,6-bis(bromomethyl)pyridine with 3,5-dimethylpyrazole and 1H-indazole yield the terdentate ligands 2,6-bis(3,5-dimethylpyrazol-1-ylmethyl)pyridine (5) and 2,6-bis(indazol-2-ylmethyl)pyridine (6). The molecular structure of the new compound 6 was determined by single-crystal X-ray diffraction. These ligands react with the CrCl3(THF)3 complex in THF to form neutral complexes of general formula [CrCl3{2,6-bis(azolylmethyl)pyridine-N,N,N}] (7, 8) which are isolated in high yields as stable green solids and characterized by means of elemental analysis, magnetic moments, IR, and mass spectroscopy. Theoretical calculations predict that the thermodynamically preferred structure of the complexes is the fac configuration. After reaction with methylaluminoxane (MAO) the chromium(III) complexes are active in the polymerization of ethylene.  相似文献   

17.
Two sets of Schiff base ligands, set-1 and set-2 have been prepared by mixing the respective diamine (1,2-propanediamine or 1,3-propanediamine) and carbonyl compounds (2-acetylpyridine or pyridine-2-carboxaldehyde) in 1:1 and 1:2 ratios, respectively and employed for the synthesis of complexes with Ni(II) perchlorate and Ni(II) thiocyanate. Ni(II) perchlorate yields the complexes having general formula [NiL2](ClO4)2 (L = L1 [N1-(1-pyridin-2-yl-ethylidine)-propane-1,3-diamine] for complex 1, L2 [N1-pyridine-2-ylmethylene-propane-1,3-diamine] for complex 2 or L3 [N1-(1-pyridine-2-yl-ethylidine)-propane-1,2-diamine] for complex 3) in which the Schiff bases are mono-condensed terdentate whereas Ni(II) thiocyanate results in the formation of tetradentate Schiff base complexes, [NiL](SCN)2 (L = L4 [N,N′-bis-(1-pyridine-2-yl-ethylidine)-propane-1,3-diamine] for complex 4, L5 [N,N′-bis(pyridine-2-ylmethyline)-propane-1,3-diamine] for complex 5 or L6 [N,N′-bis-(1-pyridine-2-yl-ethylidine)-propane-1,2-diamine] for complex 6) irrespective of the sets of ligands used. Formation of the complexes has been explained by anion modulation of cation templating effect. All the complexes have been characterized by elemental analyses, spectral and electrochemical results. Single crystal X-ray diffraction studies confirm the structures of four representative members, 1, 3, 4 and 5; all of them have distorted octahedral geometry around Ni(II). The bis-complexes of terdentate ligands, 1 and 3 are the mer isomers and the complexes of tetradentate ligands, 4 and 5 possess trans geometry.  相似文献   

18.
The synthesis of a novel 5-(4-vinylphenyl)-CyMe4-BTPhen actinide selective ligand using selenium free synthetic procedures is reported. For the first time, we report the electrospinning of this actinide selective ligand into a polystyrene fiber and investigate its selective removal of Am(III) from Eu(III) and Am(III) from Cm(III). At 4?M HNO3, the resulting fibrous solid extractant produced separation factors of SFAm/Eu?≈?57 and a small, but significant separation of SFAm/Cm?≈?2.9.  相似文献   

19.
The Schiff base tetradentate ligands N,N-bis-(3,5-dimethyl-1-p-tolyl-1H-pyrazol-4-ylmethylene)-ethane-1,2-diamine (H2L1), N,N-bis-(3,5-dimethyl-1-p-sulfonyl-1H-pyrazol-4-ylmethylene)-ethane-1,2-diamine (H2L2), N,N-bis-(3,5-dimethyl-1-p-tolyl-1H-pyrazol-4-ylmethylene)-benzene-1,2-diamine (H2L3) and N,N-bis-(3,5-dimethyl-1-p-sulfonyl-1H-pyrazol-4-ylmethylene)-benzene-1,2-diamine (H2L4) were prepared from the reaction between 5-oxo-3-methyl-1-p-tolyl-1H-pyrazole-4-carbaldehyde or 4-(4-formyl-5-oxo-3-methyl-pyrazol-1-yl)-benzenesulfonic acid and o-phenylenediamine or ethylenediamine. And these are characterized by elemental analysis, FT-IR, 1H NMR and GC–MS. The corresponding Schiff base complexes of Mn(III) were prepared by condensation of [Mn33-O)(OAc)6(H2O)3]·3H2O with ligands H2L1, H2L2, H2L3 and H2L4. All these complexes have been characterized by elemental analysis, magnetic susceptibility, X-ray crystallography, conductometry measurement, FT-IR, electronic spectra and mass (FAB) spectrometry. Thermal behaviour of the complexes has been studied by TGA, DTA and DSC. Electronic spectra and magnetic susceptibility measurements indicate octahedral stereochemistry of manganese (III) complexes, while non-electrolytic behaviour complexes indicate the absence of counter ion.  相似文献   

20.
Reactions of pyridine N-oxide with ethylenediamine and o- and p-phenylenediamines in the presence of p-toluenesulfonyl chloride in alkaline medium lead to the formation of the corresponding N,N′-bis-(p-tolylsulfonyl)-N,N′-bis(pyridin-2-yl)diamines as a result of reductive acylamination.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号