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The synthesis, characterization, and metal ion uptake studies of two chelating resins with multiple functional groups are reported. The chelating resins were synthesized by condensing a phenolic Schiff base derived from 4,4′‐diaminodiphenylmethane and o‐hydroxyacetophenone with formaldehyde or furfuraldehyde. The resins readily absorbed transition metal ions, such as Cu2+ and Ni2+, from dilute aqueous solutions. The Schiff base, resins, and metal polychelates were characterized by various instrumental techniques, such as elemental‐analysis, ultraviolet–visible spectroscopy proton and carbon‐13 nuclear magnetic resonance spectroscopy (1H‐NMR and 13C‐NMR, respectively), X‐ray diffraction (XRD), and thermogravimetric–differential thermogravimetric analyses (TG–DTG). The 1H‐NMR and 13C‐NMR studies were used to determine the sites for aldehyde condensation with the phenolic moiety. Fourier transform infrared data provided evidence for metal–ligand bonding. Thermogravimetric analysis was employed to compare the relative thermal stabilities of the resins and the polychelates. The TG data were fitted into different models and subjected to computational analysis to calculate the kinetic parameters. The XRD data indicate that the incorporation of metal ion into the resin matrix significantly enhanced the degree of crystallinity of the material. The extent of metal‐ion loading into the resins was studied in competitive and noncompetitive conditions, varying the time of contact, metal ion concentrations, and pH of the reaction medium in a suitable buffer medium. The furfuraldehyde‐condensed resin was more effective in removing metal ions than the formaldehyde‐condensed resins. The resins were selective for Cu2+, resulting in separation of Cu2+ and Ni2+ from the mixture at pH 5.89. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 570–581, 2003 相似文献
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Saeed Rayati Marjan Koliaei Fatemeh Ashouri Sajjad Mohebbi Andrzej Wojtczak Anna Kozakiewicz 《Applied Catalysis A: General》2008,346(1-2):65-71
Tetradentate Schiff base ligands, derived from aromatic aldehydes and aliphatic diamine (2,2′-dimethylpropandiamine), and their vanadyl complexes have been prepared and characterized. Catalytic potential of these complexes was tested for the oxidation of cyclooctene and styrene using tert-butylhydroperoxide (TBHP) as oxidant. The effects of molar ratio of oxidant to substrate, temperature and solvent have been studied. Excellent selectivity of epoxidation for cyclooctene and good selectivity for styrene were obtained. The mechanism of oxidation has also been discussed. 相似文献
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Saeed Rayati Nasrin Sadeghzadeh Hamid Reza Khavasi 《Inorganic chemistry communications》2007,10(12):1545-1548
New dioxovanadium(V) complex bearing tridentate ligand of 1:1 condensation of 1,2-propylenediamine and 2′-hydroxy-4′-methoxyacetophenone has been synthesized and characterized by IR and 1H NMR spectroscopy and elemental analysis. The single-crystal structure of the complex shows that each vanadium(V) ion is six-coordinate through three bonds to oxo groups and through bonds to the tridentate Schiff base ligand. The title complex is used as catalyst for the selective epoxidation of cyclooctene. The catalytic system described here is an efficient and inexpensive method for the oxidation of olefins, with the advantages of high activity, selectivity, and short reaction time. 相似文献
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Yinuo Wu Fei Mao Fanchao Meng Xingshu Li 《Advanced Synthesis \u0026amp; Catalysis》2011,353(10):1707-1712
The asymmetric vanadium‐catalyzed oxidation of 1,3‐dithianes from aldehydes and ketones by β‐amino alcohol‐derived Schiff base ligands with two stereogenic centers was investigated. Using aqueous hydrogen peroxide as the oxidant and the Schiff base 3b as a chiral ligand, a variety of 1,3‐dithianes derived from aldehydes were easily converted into the corresponding mono‐sulfoxides in good yields (81–88%) with excellent enantioselectivities (up to 99% ee). Additionally, 99% ee was obtained for the enantioselective vanadium‐catalyzed oxidation of the 1,3‐dithianes derived from ketones. We found a slight kinetic resolution when using a higher ratio of hydrogen peroxide during the oxidation of the aldehyde‐derived 1,3‐dithianes but not in the ketone‐derived 1,3‐dithianes. 相似文献
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在非水溶剂中合成出一种未见报道的新型席夫碱试剂(HL):1-苯基-3-甲基4-萘乙酰基-吡唑啉酮-5(PMNAP)缩2-氨基苯并噻唑及其4种过渡金属配合物.由元素分析、化学方法、质谱和摩尔电导值推测出配合物的组成为ML·H2O[M=Cu2+、Pb2+、Ni2+、Zn2+],通过红外光谱、紫外光谱、热重谱和核磁共振氢谱等手段对配体和配合物进行了结构表征并做了初步的抑菌活性实验.表征结果显示:配体在测试条件下以酮式和烯醇式结构共存,配位时酮式可能转化为烯醇式结构按去质子的方式以1分子吡唑啉酮环羟基和1分子H2O上的两个0原子以及亚胺基和苯并噻唑环上的两个N原子与过渡金属中心离子成键,配合物的配位数为4;抑菌实验结果表明:配合物比配体对枯草杆菌、大肠杆菌、酵母菌和金黄色葡萄球菌具有更强的抑制作用. 相似文献
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5-硝基,N(2-羟基乙基)水杨醛亚胺Schiff碱的合成 总被引:2,自引:3,他引:2
用自制的5-硝基水杨酸设计合成了5-硝基,N(2-羟基乙基)水杨醛亚胺Schiff碱,其组成和结构已由元素分析和红外光谱所表征。 相似文献
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Gulmira Zhumadilova Marziya Yashkarova Larisa Bimendina Sarkyt Kudaibergenov 《Polymer International》2003,52(6):876-882
Novel linear and crosslinked copolymers of acrylic acid and Schiff base, containing the amine groups in the main chain and the carboxylic groups in the side chain, have been synthesized by the Michael addition reaction followed by radical copolymerization. The copolymers that exhibited poly(ampholyte–electrolyte) behaviour were used to prepare complexes by reaction with anionic (poly(acrylic acid), poly(styrene sodium sulfonate)), cationic (polyethyleneimine, poly(hexamethylene guanidine)) and non‐ionic (poly(N‐vinylpyrrolidone), poly(ethylene glycol), poly(vinyl alcohol)) polymers. The influence of external factors, such as solvent quality, temperature, pH and ionic strength, on phase (coil–globule) and volume (swelling–collapse) transitions has been studied. © 2003 Society of Chemical Industry 相似文献
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以壳聚糖和对二甲氨基苯甲醛为原料合成壳聚糖希夫碱,以壳聚糖希夫碱为底物,采用反相悬浮聚合法,制备壳聚糖希夫碱微球。对二者的吸附性能进行比较研究。结果表明,希夫碱微球的吸附性能优于壳聚糖希夫碱,对四氧化三铁的吸附容量分别为113.179 mg/g和39.279 mg/g,对亚甲基蓝的吸附平衡时间均为150 min,饱和吸附容量随着亚甲基蓝初始质量浓度的增大而增大,且微球的吸附容量大于壳聚糖希夫碱,吸附率不随浓度增大单调递增,而是有一极大值。 相似文献
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通过二茂铁甲醛与两种二胺在无水乙醇中缩合合成了两个新型的含有双二茂铁基的Schiff碱,并通过元素分析,核磁共振氢谱,红外光谱和紫外光谱的测定确证了其结构。 相似文献
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中性条件下,以二茂铁甲醛和对苯二胺为原料,合成了二茂铁基席夫碱,考查了反应温度和时间对产率的影响,并测得其本征态室温电导率σ=1.26×10-9 S·cm-1。利用Fe3+、Al3+、Ti3+盐对二茂铁基席夫碱进行了掺杂,探讨了掺杂量和掺杂温度对产物室温电导率的影响,研究了掺杂产物电导率与温度的变化关系,并用红外光谱、紫外光谱和电子探针对产物结构和组成进行了表征。结果表明:经金属盐掺杂后,电导率可提高4~5个数量级, 根据Arrhenius曲线得到了化合物的电活化能在0.09~1.54 eV范围内,表明了它们具有较好的半导体性能。 相似文献
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A novel polymeric Schiff base was synthesized by the reaction of a Schiff base from 2,4‐dihydroxy benzaldehyde and aniline with acryloyl chloride and was polymerized in methyl ethyl ketone at 70°C with benzoyl peroxide as a free‐radical initiator. Polychelates were obtained in an alkaline solution of poly(2‐hydroxy‐4‐acryloyloxy‐N‐phenylbenzylidine) with aqueous solutions of metal ions such as Cu(II), Ni(II), Co(II), Ca(II), Cd(II), Mn(II), and Zn(II). The polymeric Schiff base and polychelates were characterized with elemental analysis and spectral studies. The elemental analysis of the polychelates suggested that the metal‐to‐ligand ratio was 1:2. The IR spectral data of the polychelates indicated that the metals were coordinated through the nitrogen and oxygen of the phenolic ? OH group. Diffuse reflectance spectra, electron paramagnetic resonance, and magnetic moment studies revealed that the polychelates of the Cu(II) complex were square‐planar, those of the Ni(II), Mn(II), and Co(II) complexes were octahedral, and those of the Ca(II), Cd(II), and Zn(II) complexes were tetrahedral. X‐ray diffraction studies revealed that the polychelates were highly crystalline. The thermal properties of the Schiff base and polychelates were also examined. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 494–500, 2004 相似文献
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Monomeric Schiff base derived from salicylaldehyde and 1,3‐diaminopropane was subjected to polycondensation reaction with formaldehyde and piperazine in basic medium. The resin was found to form polychelates readily with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) metal ions. The materials were characterized by elemental analysis, spectral studies (IR, 1H‐NMR, 13C‐NMR, and UV–visible), magnetic moment measurements, and thermal analysis. The electronic spectra and magnetic moment measurements of the synthesized polychelates confirmed the geometry of the central metal ion. Metal–resin bonds were registered in the IR spectra of the polychelates. The thermogravimetric analysis data indicated that the polychelates were more stable than the corresponding polymeric Schiff base. All the synthesized metal–polychelates showed excellent antibacterial activities against the selected bacteria. The antimicrobial activities were determined by using the shaking flask method, where 25 mg/mL concentrations of each compound were tested against 105 CFU/mL bacteria solutions. The number of viable bacteria was calculated by using the spread‐plate method, where 100 μL of the incubated antimicrobial agent in bacteria solutions were spread on agar plates, and the number of bacteria was counted after 24 h of incubation period at 37°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
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