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1.
合成了开链冠醚Schiff碱配体H2L(H2L=N,N′-双(邻羟苯亚甲基)-3,6-二氧杂-1,8-二氨基辛烷).详细研究了该配体在不同溶剂中和过渡金属离子存在下的荧光光谱,探讨了溶剂极性和不同金属离子对其荧光光谱的影响.结果表明:溶剂的极性和金属离子对其荧光性质有较大影响,随着溶剂极性的减小,配体的荧光增强,且谱峰发生蓝移.金属离子Zn2+、Cd2+对配体具有荧光增敏作用,Ni2+、Cu2+具有荧光猝灭作用.探讨了配体与金属离子结合的pH范围,结果显示最佳pH值为7—8.  相似文献   

2.
合成了三种Schiff碱型羧酸开链冠醚与Cu(二价)的多核固体配合物,对配合物的性质进行了分析鉴定,对其表征进行了研究。  相似文献   

3.
合成了三种Schiff碱型羧酸开链冠醚与Cu(二价 )的多核固体配合物 ,对配合物的性质进行了分析鉴定 ,对其表征进行了研究  相似文献   

4.
开链冠醚的合成   总被引:4,自引:1,他引:3  
冯民 《化学世界》1994,35(9):463-466
本文以苄胺和2-甲氧基-1-氨甲基萘为原料,与三甘酰氯作用,合成了两种新的酰胺型开链冠醚,这两种新的化合物经红外、核磁、质谱和元素分析证实,与预期结果相符。  相似文献   

5.
首次合成了以对氯苯胺和苯胺为端基的4种双酰胺型开链冠醚,并对其进行了核磁氢谱、碳谱、元素分析及质谱的结构表征。  相似文献   

6.
以对氨基苯甲酸乙酯为端基合成了3种酰胺型开链冠醚,并通过IR、^1HNMR、MS和元素分析确证了它们的结构.  相似文献   

7.
苯二氧基二乙酸的制备及其酸离解常数的测定   总被引:2,自引:0,他引:2  
利用苯二酚与一氯乙酸在碱性条件下的成醚反应 ,制备了三种苯二氧基二乙酸 ,通过采用本生阀密封装置和控制反应体系的 p H值 ,减少了酚羟基的氧化和一氯乙酸的水解反应 ,提高了反应的产率和选择性。用自动电位滴定仪测定了三种苯二氧基二乙酸的酸离解常数 ,在数据处理上采用了分段回归分析的方法 ,提高了精确度 ,Excel电子表格的引用使得数据的处理变得更为简便和准确。运用 CNDO/2量化计算方法对离解常数的测定结果进行了讨论。  相似文献   

8.
刘志贤  陈钢进 《化学试剂》1996,18(5):260-262
研究了meso-四卟啉和meso-四卟啉的离解常数。TBPhP的离解常数为:pKa4=1.13.pKa3=1.88,pKA2=12.21;TTPS的离解常数为:pKa4=4.47,pKa3=6.26。外还发现了两卟啉的酸碱诱导聚合。  相似文献   

9.
刘飞  蓝春波  张圣辰  赵景婵 《化学试剂》2014,(7):629-631,642
采用高效液相色谱法(HPLC)测定了桐油酸、3-正丁基-6-(1-癸烯酸甲酯基)-4-环己烯二酸(C23二酸甲酯)和3-正丁基-6-(1-癸烯酸基)-4-环己烯二酸(C22三元羧酸)的离解常数。用HPLC测定样品在不同pH(2.00~12.00)下的容量因子,通过最小二乘法计算出相应的离解常数。通过不同流动相比例下的离解常数计算出样品在纯水中的离解常数。实验得到的结果与用ACD/Lab软件计算得到的结果相近。桐油酸的pKa为4.79;C23二酸甲酯的pKa1为3.81,pKa2为5.78;C22三元羧酸的pKa1为3.68,pKa2为4.77,pKa3为5.73。  相似文献   

10.
以苯硫脲基乙酸为端基的开链冠醚的合成及其性质研究   总被引:3,自引:0,他引:3  
白宝林  李满秀 《化学试剂》1996,18(5):273-275
由NH4CNS、ClCH2COOH和开链冠醚桥联二芳胺在无水EtOH中回流,合成了3个以苯硫脲基乙酸为端基的开链冠醚,并经IR、^1HNMR,MS确证了其结构,。初步试验了其与金属离子 的络合性能。  相似文献   

11.
A.S. Fouda  M. Abdallah 《Desalination》2010,250(2):538-988
The effect of crown ethers on the corrosion behavior of stainless steel (type 430) in 2M HCl solution was studied using weight loss and galvanostatic polarization methods. The inhibition efficiency was found to increase with increasing the concentration of the inhibitors and deceases with increasing the temperature. The polarization studies showed that crown ethers act as mixed-type inhibitors. The inhibiting effect of these compounds was interpreted in view of their adsorption on the metal surface. The adsorption of these compounds was found to obey Temkin adsorption isotherm. Surface examination and morphological studies were tested using scanning electron microscope (SEM) and energy dispersive X-ray (EDX). All the results achieved were compared and discussed.  相似文献   

12.
A series of new thiacrown ethers derived quinoline 79 were synthesized in good yield and in a simple way. Their transition metal ions complexation was studied using a conductometric method in acetonitrile at 25°C. Crowns 7 and 8 showed a continuous decrease in the molar conductances in their complexation with Ag+, Cu2+, Hg2+ and Zn2+ which begins to level off at a molar ratio of 1:1 crown to metal, indicating the formation of 1 stable 1:1 complex. On the other hand, crown 9 showed the formation of 1:1 complexes only with Ag+, Cu2+, Hg2+. The in vitro, a preliminary antimicrobial, antioxidant and cytotoxic effects on breast tumor cells were also reported. Five bacterial test strains were included in the present study. Antioxidant activity was measured in terms of the radical scavenging ability and decolorization of 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radicals. Cytotoxic effect of thiacrown was evaluated using MDA MB-231 cell line (human breast adenocarcinoma, ATCC HTB-26).  相似文献   

13.
张来新 《陕西化工》2014,(4):732-734
介绍了冠醚化学的产生、发展及应用,详细介绍了:几种新型臂式冠醚及其超分子金属配合物的合成;取代冠醚及其金属配合物的合成及应用;新型氮杂冠醚及其金属配合物的合成及应用。并对冠醚化学的发展进行了展望。  相似文献   

14.
四氢咔唑酮离解常数的光度法测定   总被引:1,自引:0,他引:1  
研究了四氢咔唑酮在不同比例的乙醇.水混合溶剂中及不同酸度下的吸收光谱,提出了采用紫外分光光度法测定四氢咔唑酮在水中离解常数的方法.试验证明:在不同比例的乙醇.水混合溶剂中,四氢咔唑酮的离解常数与乙醇的体积分数存在良好的线性关系,通过外推至乙醇含量为零,可求得在实验条件下四氢咔唑酮在水溶液中的离解常数pKb为14.04.  相似文献   

15.
Two novel chitosan derivatives—crosslinked chitosan dibenzo‐16‐c‐5 acetate crown ether (CCTS‐1) and crosslinked chitosan 3,5‐di‐tert‐butyl dibenzo‐14‐c‐4 diacetate crown ether (CCTS‐2)—were synthesized by the reaction of crosslinked chitosan with dibenzo‐16‐c‐5 chloracetate crown ether and 3,5‐di‐tert‐butyl dibenzo‐14‐c‐4 dichloracetate crown ether with the intent of forming polymers that could be used in hazardous waste remediation as toxic metal‐binding agents in aqueous environments. Their structures were confirmed with elemental analysis, infrared spectral analysis, and X‐ray diffraction analysis. In the infrared spectra of CCTS‐1 and CCTS‐2, the characteristic peaks of aromatic backbone vibration appeared at 1595 cm−1 and 1500 cm−1; the intensity of the N H and O H stretching vibration in the region of 3150–3200 cm−1 decreased greatly. The X‐ray diffraction analysis showed that the peak at 2θ = 20° decreased greatly in CCTS‐1 and CCTS‐2. The adsorption and selectivity properties of CCTS‐1 and CCTS‐2 for Pb2+, Cu2+, Cr3+, and Ni2+ were studied. Experimental results showed that the two crosslinked chitosan derivatives had not only good adsorption capacities for Pb2+, Cu2+, but also high selectivity for Pb2+, Cu2+ in the coexistence of Ni2+. For aqueous systems containing Pb2+, Ni2+, or Cu2+, Ni2+, CCTS‐1 only adsorbed Pb2+ or Cu2+. For aqueous systems containing Pb2+, Cr2+ and Ni2+, CCTS‐2 had high adsorption and selectivity properties for Pb2+. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 2069–2074, 1999  相似文献   

16.
微波辐射下芳香族醚的合成   总被引:5,自引:2,他引:5  
戴桂元  胡涛  刘蕴  刘德龙 《化学试剂》2003,25(3):166-168
微波辐射下,酚与硫酸二甲酯或溴乙烷在碱性溶液里合成芳香醚的反应10-20min即可完成,为合成芳香族醚提供了一种新的途径。  相似文献   

17.
The autoprotolysis constant KHS of formic acid/water mixtures as solvent has been calculated from acid-base potentiometric titration curves. A correlation of the acidity scale pKHS of each medium versus pure water has been implemented owing to the Strehlow R0(H+) electrochemical redox function. The results show that formic acid/water mixtures are much more dissociated than pure water; such media are sufficiently dissociated to allow electrochemical measures without addition of an electrolyte. It has also been shown that for a same H+ concentration the activity of protons increases with formic acid concentration. For more than 80 wt.% of formic acid the acidity is sufficiently increased to locate the whole acidity scale pKHS in the super acid medium of the generalized acidity scale pHH2O.  相似文献   

18.
傅琼瑶  李娜  蹇丽  季玉祥  张军 《化学试剂》2012,34(3):272-274
经取代、氯乙酰化、成环3步反应合成两种新的硫氮杂冠醚化合物,产率>90%。该合成方法具有反应条件温和,容易提纯等优点。化合物结构经IR、NMR、MS以及元素分析确定。  相似文献   

19.
用2,4-二羟基-5-乙酰苯乙酮、二胺基硫脲与水杨醛反应合成了新型不对称席夫碱配体及其铜(II)iE合物,通过元素分析、1HNMR、IR、uV—vis等手段对配体及其配合物进行了组成和结构表征,并采用邻苯三酚自氧化法测定了它们模拟超氧化物歧化酶(SOD)活性。结果表明,它们均具有良好的SOD活性。  相似文献   

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