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91.
含硫希夫碱的合成研究 总被引:3,自引:0,他引:3
合成了一种含硫希夫碱—1,4-双[(2’-甲醛缩硫代氨基脲基)苯氧甲基]乙烷及其中间产物1,4-双[(2’-甲醛)苯氧甲基]乙烷.其结构经元素分析,IR和1H NMR表征。 相似文献
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93.
Jan F. Biernat Maria Bochenska Jerald S. Bradshaw Hiroyuki Koyama Gypzy Lindh John D. Lamb James J. Christensen Reed M. Izatt 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(6):729-738
Five new macrocyclic ligands each containing two sulfonamide groups have been prepared. Three of these compounds contain one or two chloro substituents and the other two have one or two pyridine subcyclic units. A seventeen-membered ring ligand (4) was found to be an excellent transport agent for all alkali metal cations in a water-methylene chloride-water bulk liquid membrane system when the pH of the source phase was 13 or higher. The chlorine-substituted analog (5) was a poor transport agent for the alkali metal cations possibly because the chlorine atom blocked entry to the macrocycle cavity. An open-chain analog containing two sulfonamide groups was particularly effective in transporting cesium ions. 相似文献
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95.
SynthesisandMagneticPropertiesofBinuclearMn(Ⅱ)ComplexeswithAlkoxideBridgeYanShi-ping;FanBo;LiaoDai-zheng;JiangZong-huiandWang... 相似文献
96.
本文以2.6─二乙酰吡啶和1,3一二氨基一2一丙醇通过模板合成西佛碱大环配体H_2L(图1),并合成了它的Co(Ⅱ)、Ni(Ⅱ)及Fe(Ⅱ)的双核配合物,重点讨论了Co_2(HL)(ClO_4)_2(NO_3)·4H_2O配合物的光谱与磁性。变温磁化率数据(4─300K)通过用最小二乘法与理论方程拟合,得到磁参数为J=-1.24cm ̄(-1),θ=-0.24K,表明配合物中co(Ⅱ)-Co(Ⅱ)间存在弱的反铁磁相互作用,分子间也存在反铁磁相互作用。 相似文献
97.
The synthesis, characterization and crystal structure analysis of the ammonium salt of the dioxovanadium(V) complex NH4[VO2(salhyph)] with the tridentate Schiff base ligand derived from salicylaldehyde and benzoic acid hydrazide (H2salhyph) is reported. NH4[VO2(salhyph)] crystallizes in the monoclinic space group Pn with a = 708.8(2), b = 1444.3(3), c = 717.1(2) pm and β = 101.09(2)°. The vanadium atom of the dioxovanadium(V) moiety has a distorted square‐pyramidal coordination geometry. Extensive hydrogen bonding is observed between the ammonium cation and the oxygen atoms coordinated to the vanadium atom yielding to a two‐dimensional network, where the complex anions are arranged in a bilayer. Additional crystal packing within the bilayer appears to be controlled mostly by π stacking between the aromatic rings of the ligand. The reactions of NH4[VO2(salhyph)] with several proton acidic compounds including water, methanol, and proton acids lead to neutral monooxovanadium(V) and dioxovanadium(V) complexes ([VO2(Hsalhyph)], [V2O3(salhyph)2] and [VO(OMe)(salhyph)(HOMe)]). 相似文献
98.
采用共价接枝法, 以氨丙基-三乙氧基硅烷为氨源, 制备了一系列的NH2-SBA-15催化剂, 通过微量吸附量热技术定量地分析了该催化剂表面碱性中心的强度、数量和分布状态. 实验结果表明, SBA-15在 550 ℃焙烧6 h, 氨基硅源与SBA-15质量比为1.5, 是合成NH2-SBA-15催化剂最适宜的条件. 运用微量吸附量热技术实现了对NH2-SBA-15催化剂合成条件的优化. 相似文献
99.
D-氨基葡萄糖Schiff碱及其金属配合物的抗菌活性 总被引:16,自引:0,他引:16
The effects of D-glucosamine schiff base and its metal complexes on the growth of Aerobacter aerogenes were investigated by the microcalorimetry. Among the substances tested. Zn-SG was shown to be the most bacteriostasic, followed by Zn-o-VG and SG (with the Ic50 of 242, 287 and 320 μg•mL-1, respectively). Cu(Ⅱ)-SG showed less inhibitory effect on Aerobacter aerogenes over the concentration rang of 50~300μg•mL-1. 相似文献
100.
Based on an analysis of previously reported structures and a potential geometry fit with substrates, a new family of chiral dioxocyclam derivatives have been designed. The synthesis of those ligands was accomplished starting from l-proline and α-d-amino acids (converted to β-amino acids) with a key step of macrocyclization reaction of amino esters. All ligands were converted into neutral copper(II) complexes (amide groups underwent deprotonation of upon treatment of ligands with copper(II) acetate). The complexes exhibit the desired shape of their active surfaces, as proved by X-ray analysis. 相似文献