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1.
本文报道了一种合成硫杂冠醚聚合物的新方法。以聚(2′-氯乙基-2,3-环硫丙基醚)为预聚物与二巯基化合物通过大分子反应直接环化,一步法合成了四种以聚硫醚为主链的新型硫杂冠醚聚合物(PD1-PD4)。并测定了它们对Ag~+、Au~(3+)、Pd~(2+)、Pt~(4+)、Cu~(2+)、Hg~(2+)、Zn~(2+)、Cd~(2+)、Pb~(2+)、Mg~(2+)、K~+、Ns~+等金属离子的络合性能。结果表明:它们除不络合K~+、Na~+、Mg~(2+)、Pb~(2+)外,对其它八种离子有不同程度的络合,其中对Ag~+、Au~(3+)、Pd~(2+)等贵金属离子的络合容量较高。  相似文献   

2.
多齿络合法分离锂同位素的冠醚化学   总被引:1,自引:0,他引:1  
刘华  黄祚刚  文珂  姜标 《有机化学》2014,(2):316-324
锂的两种天然同位素锂-6和锂-7在核能工业中具有重要的作用.在众多锂同位素的分离方法和体系中,多齿络合法普遍具有较高的同位素分离系数.冠醚由于其对金属阳离子具有较强的选择性络合能力,被认为是多齿络合法分离锂同位素最有效的萃取剂.综述了冠醚及冠醚树脂在多齿络合法分离锂同位素中的应用,并简述新型金属冠醚与金属离子络合的进展,展望其在锂同位素分离中的潜在应用前景.  相似文献   

3.
 本文报道了一种合成硫杂冠醚聚合物的新方法。以聚(2′-氯乙基-2,3-环硫丙基醚)为预聚物与二巯基化合物通过大分子反应直接环化,一步法合成了四种以聚硫醚为主链的新型硫杂冠醚聚合物(PD1-PD4)。并测定了它们对Ag+、Au3+)、Pd2+、Pt4+、Cu2+、Hg2+、Zn2+、Cd2+、Pb2+、Mg2+、K+、Ns+等金属离子的络合性能。结果表明:它们除不络合K+、Na+、Mg2+、Pb2+外,对其它八种离子有不同程度的络合,其中对Ag+、Au3+、Pd2+等贵金属离子的络合容量较高。  相似文献   

4.
双冠醚化合物对某些金属离子比单冠醚具有更好的络合性能和选择性,它们合成、应用研究越来越受到人们的重视,本工作采用2,6-二羟甲基对甲氧基苯酚为缩合剂与芳香族冠醚缩聚,得到一系列具有双冠醚结构特征的新酚醛型聚苯并冠醚(简称聚冠醚),聚冠醚合成容易,并呈现了比相应单冠醚更优越的络合萃取能力和富集效率。  相似文献   

5.
报道了碲杂冠醚(TeB15C5)对Na^+、K^+、Ag^+和Pb^2+的液膜迁移能力,并与相应的全氧冠醚(B15C5)、硫杂冠醚(SB15C5)和硒杂冠醚(SeB15C5)作了比较;同时以SeB15C5对K^+的迁移为例考察了冠醚浓度和盐浓度对迁移速率的影响。  相似文献   

6.
黄载福 《有机化学》1988,8(6):519-521
用二茂铁甲醛为原料, 在BF3和少量对苯二酚存在下与二巯基化合物反应合成了八个新二茂铁硫冠醚衍生物, 研究了其中二个冠醚的络合性能, 新冠醚对金属离子特别是毒性金属离子有更高的络合选择性.  相似文献   

7.
基于冠醚配位化学和软硬酸碱理论, 设计合成了2种预期对Ag(Ⅰ)和Tl(Ⅰ)具有较强配位能力的超大环冠醚10,19-二硫杂苯并30-冠-10(DHB30C10)和10,13,17,20-四硫杂苯并31-冠-10(THB31C10). 采用溶剂萃取法考察了2种冠醚对Ag(Ⅰ)和Tl(Ⅰ)的选择萃取性能. 结果表明, 在单一体系中, DHB30C10和THB31C10对Ag(Ⅰ)的络合常数分别为9.76和13.40, 对Tl(Ⅰ)的络合常数分别为4.769和4.325. 在多元体系中, 2种冠醚对Ag(Ⅰ)均具有较强选择性, 其中DHB30C10对Cu(Ⅱ)和Ni(Ⅱ)的分离系数可达194.68和142.44, THB31C10对Cu(Ⅱ)和Ni(Ⅱ)的分离系数可达172.81和268.53, 但对Tl(Ⅰ)几乎不具有选择性. 并探讨分析了DHB30C10与THB31C10对Ag(Ⅰ)和Tl(Ⅰ)的萃取机理.  相似文献   

8.
报道了碲杂冠醚(TeB15C5)对Na+、K+、Ag+和Pb2+的液膜迁移能力,并与相应的全氧冠醚(B15C5)、硫杂冠醚(SB15C5)和硒杂冠醚(SeB15C5)作了比较;同时以SeB15C5对K+的迁移为例考察了冠醚浓度和盐浓度对迁移速率的影响,结果表明,TeB15C5对Na+、K+和Pb2+的迁移能力比SB15C5和SeB15C5强,但对Ag+的迁移速率比后两者慢;SeB15C5对Ag+的迁移速度比SB15C5快,两者对Ag+的选择性都相当高,可以用来分离和回收银等贵重金属。  相似文献   

9.
近年来国内外相继报道了在冠醚核心上引入取代基合成出一系列具有液晶特性的冠醚化合物,它们除具有普通液晶的电光、电磁及超声等特性外,还具有选择性络合金属离子的能力。研究这类化合物结构及性能将有助于选择和制备对金属离子具有高度识别能力的输送膜。为此,我们研究了以二苯并-18-冠-6(DB-18-C-6)及苯并-15-冠-5(B-15-C-5)为核心衍生的胆甾型冠醚化合物。经红外、核磁、质谱及元素分析确定其结构,由差热分析和偏光显微镜观察证明其具有液晶特性,并用电导法探讨了该系列液晶化合物与KClO_4在25℃时的络合特性,测定了络合比及络合常数。  相似文献   

10.
本文报道了一类新型全硫冠醚聚合物的合成,即由聚环硫氯丙烷与二巯基化合物反应,生成具有冠醚环结构单元的交联型聚合物。并研究了这些聚合物的对金属离子的络合性能。  相似文献   

11.
为了进一步研究亚丙基冠醚的络合行为,合成了三种含1,3-亚丙基冠醚,即2,3-苯并-1,4,7,11-四氧-环十三-2-烯(苯并-13-冠-4)(1)、2,3-苯并-1,4,8,11,14-五氧-环十七-2-烯(苯并-17-冠-5)(2)、2,3-苯并-1,4,7,10,14,17-六氧-环十九-2-烯(苯并-19-冠-6)(3)。通过元素分析、红外光谱、质谱、核磁共振谱和 X-衍射晶体结构分析,确证了它们的结构。  相似文献   

12.
A new series of macrocyclic polyether-diesler compounds ( 3-12 ) have been prepared by treating various oligoethylene glyeols or mercaplans with oxalyl chloride. The compounds prepared were: 1,4,7,10,13-pentaoxacyclopentadecane-2,3-dione ( 3 ), 1,4,7,1 3-tetraoxa-10-thiacyclopenta-decane-2,3-dione ( 4 ), 1,4,10-lrioxa-7,13-dithiacyclopenladecane-2,3-dione ( 5 ), 1,4,7,10,13,16-hexaoxacyclooctadecane-2,3-dione ( 6 ), 1,4,7,10,13, 16-hexaoxacyclooctadecane-2,3,11,12-tetra-one ( 7 ), 1,4,10,13-tetraoxa-7,16-dithiacyclooctadecane-2,3,11,12-tetraone ( 8 ), 7,16-dioxa-1,4, 10,13-letralhiacyclooctadecane-2,3,11,12-tctraone ( 9 ), 1,4,7,10,13,16-hexathiacyclooctadecane-2,3,11,12-tetraone ( 10 ), 1,4,7,10,13,16,19-heptaoxacyclohencicosane-2,3-dione (11), and 1,4,7, 10,13,16,19,22-octaoxacyclolelracosane-2,3,14,15-letraone ( 12 ).  相似文献   

13.
The complexation behavior of nicotinamide with macrocyclic polyethers viz, 15-crown-5, benzo-15-crown-5, 18-crown-6, dicyclohexano-18-crown-6, dibenzo-18-crown-6, dibenzo-24-crown-8, 1,4,7,10,13,16-hexathiacyclooctadecane, monoaza-15-crown-5, 1,4,10-trioxa-7,13-diaza-cyclopentadecane, 5,6,14,15-dibenzo-1,4-dioxa-8,12-diazacyclopentadecane, 7,16-dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane, 1,4,7-tritosyl-1,4,7-triazacyclononane, 1,4,7,10-tetratosyl-1,4,7,10-tetraazacyclododecane and 1,4,8,11-tetraazacyclooctadecane has been studied in dimethylsulphoxide (DMSO) and 90% DMSO + water using differential pulse polarography and complexation constants have been reported. Nicotinamide forms stable complexes with six-membered coronand rings of the crown ethers. The nature of the atoms (oxygen, sulfur and nitrogen) in the coronand ring is observed to affect the stability of the complex. The stoichiometry and stability constants of the complexes were determined by monitoring the shifts in peak potentials of the polarograms of nicotinamide against the ligand concentration. The Gibbs free energy change turns out to be negative at 25°C, which indicates the spontaneity of the binding of nicotinamide with crown ethers. The mole ratio of nicotinamide to the macrocyclic compound was also determined and it was found that the complexes were of 1:1 type with respect to crown ethers. The tendency of nicotinamide to form complexes with macrocycles is found to be greater in DMSO than in DMSO + water.  相似文献   

14.
Abstract

For macrocyclic bases such as: 1-aza-15-crown-5 (N15C5),1,4,10-trioxa-7,13-diazacyclopentadecan (21), 1,7,10,16-tetraoxa-4,13-diazacyclooctadecan (22) and 1, 4, 7, 13, 16-pentaoxa-10, 19-diazacycloheneicosane (23), the kinetics of deprotonation and protonation reactions in the presence of monovalent cations was studied using the temperature jump technique. For the sake of comparison, the measurements were also performed for 1,4-diazabicyclo[2,2,2]octane (DABCO) base, which does not form complexes with monovalent cations. The monovalent cations affect the temperature dependence of the kinetic parameters of deprotonation. They also affect the activation parameters, which is shown by a distribution of ΔH≠ and ΔS≠ values, but do not influence the value of ΔG≠.  相似文献   

15.
Two new series of macrocyclic polyether-diester ligands ( 4-15 ) containing a pyridine subcyclic unit have been prepared by treating various oligoethylene glycols and sulfur-containing oligo-ethylene glycols with 2,6- and 3,5-pyridine dicarbonyl chlorides. The compounds prepared from 2,6-pyridine dicarbonyl chloride were: 3,6,9,12-tetraoxa-18-azabicyclo[12.3.1 ]oetadeca-1(18), 14,16-triene-2,13-dione ( 4 ); 3,6,9,12,15-pentaoxa-21-azabieyclo[15.3.1]heneicosa-1(21),17,19-triene-2,16-dione ( 5 ); 3,6,12,15-tetraoxa-9-thia-21-azabicyclo[15.3.1 ]heneicosa-1(21),17,19-tri-ene-2,16-dione( 6 ); 3,9,15-trioxa-6,12-dithia-21-azabicyclo[15.3.1]heneicosa-1(21),17,19-triene-2,16-dione ( 7 ); 3,6,9,12,15,18-hexaoxa-24-azabicyclo[18.3.1 ]tetracosa-1(24),20,22-triene-2,19-dione ( 8 ); 3,6,9,12,15,18,21-heptaoxa-27-azabicyclo[21.3.1]heptacosa-1(27),23,25-triene-2,22-dione ( 9 ); and the corresponding analogues from 3,5-pyridine dicarbonyl chloride ( 10-15 ). The solid potassium thiocyanate complex of compound 5 was also prepared.  相似文献   

16.
Six new ent-kaurane-type diterpenoids were isolated from the leaves of the endemic Vietnamese medicinal plant Croton tonkinensis GAGNEP. (Euphorbiaceae) together with three known ent-11alpha-acetoxy-7beta,14alpha-dihydroxykaur-16-en-15-one (1), ent-kaur-16-en-15-one 18-oic acid (5) and ent-18-hydroxykaur-16-ene (7). Their structures were determined by spectroscopic analyses to be ent-7beta-acetoxy-11alpha-hydroxykaur-16-en-15-one (2), ent-18-acetoxy-11alpha-hydroxykaur-16-en-15-one (3), ent-11alpha-acetoxykaur-16-en-18-oic acid (4), ent-15alpha,18-dihydroxykaur-16-ene (6), ent-11alpha,18-diacetoxy-7beta-hydroxykaur-16-en-15-one (8), and ent-(16S)-1alpha,14alpha-diacetoxy-7beta-hydroxy-17-methoxykauran-15-one (14). ent-Kaurane-type diterpenoids from Croton tonkinensis 2-4, 6, and 9-13, were tested for toxicity in the brine shrimp lethality assay. Compounds 9, 10, and 12 demonstrated significant activity, compounds 2, 3, 6, and 11 showed weak activity, and compounds 4 and 13 were inactive.  相似文献   

17.
In this study two novel pendant hand-basket type calixarene gas chromatography stationary phases were prepared by hydrosilylation of ω-undecenyloxymethyl dimethyl calix[4]-15C5 and ω-undecenyloxymethyl dimethyl calix[4]-18C6 with dichloromethane followed by condensation reaction with silanol-terminated polydimethylsiloxane. Important stationary phase properties of these two novel stationary phases such as column efficiency, polarity, and selectivity were examined and compared with those of ω-undecyloxymethyl-18-crown-6, 2,3-benzo-9-propyloxymethyl-15-crown-5 and 2,3-benzo-11-propyloxymethyl-18-crown-6. Excellent thermostability from 60 to 330°C with onset bleeding temperatures at 308°C have been found. The mechanism of specific selectivity for position isomers based on the calix[4]crown ether ring, the molecular size of the solute and its shape are discussed.  相似文献   

18.
段中余  张衡益  刘育 《化学学报》2005,63(8):752-756
通过11,12-苯并-1,7,10,13-四氧杂-4-氮杂环十五烷-11-烯(苯并氮杂-15-冠-5)分别与间二苄溴, 间苯二甲酰氯和对苯二甲酰氯反应, 合成了N,N'-间二苄基双(苯并氮杂-15-冠-5) (1)、N,N'-间苯二甲酰基双(苯并氮杂-15-冠-5) (2)和N, N'-对苯二甲酰基双(苯并氮杂-15-冠-5) (3) 等三个芳香桥式双(苯并氮杂-15-冠-5)衍生物, 并解析了化合物3的晶体结构. 进而采用溶剂萃取的方法研究了它们与一价金属阳离子的键合行为. 结果表明, 双冠醚2对碱金属钠离子和重金属铊离子表现出较高的选择萃取能力, 而双冠醚1对重金属银离子表现出较高的选择萃取能力.  相似文献   

19.
本文采用微量电导滴定技术和计算机拟合,获得在DMF中Na~+和K~+与2,3-苯并-11-甲基-18-冠-6(BCl-18C6),2,3-苯并-8,15-二甲基-18-冠-6(BC2-18C6),2,3-苯并-8,11,15-三甲基-18-冠-6(BC3-18C6)的配合物的稳定常数及反应热焓,并对所得结果进行了讨论。  相似文献   

20.
本文采用微量电导滴定技术和计算机拟合,获得在DMF中Na+和K+与2,3-苯并-11-甲基-18-冠-6(BCl-18C6),2,3-苯并-8,15-二甲基-18-冠-6(BC2-18C6),2,3-苯并-8,11,15-三甲基-18-冠-6(BC3-18C6)的配合物的稳定常数及反应热焓,并对所得结果进行了讨论。  相似文献   

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