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1.
A series of lipophilic derivatives of benzo-12-crown-4 and naphtho-12-crown-4 has been synthesized. The behavior of the prepared derivatives in membrane ion-selective electrodes has been studied. Selectivity changes dependent on the position and number of substituents have been observed.  相似文献   

2.
Synthesis and Crystal Structure of [Na(DB24C8)]2(WMo5O19)   总被引:4,自引:1,他引:4  
鲁晓明  刘顺诚 《结构化学》1995,14(2):157-160
SynthesisandCrystalStructureof[Na(DB24C8)]_2(WMo_5O_(19))¥LuXiao-Ming;LiuGuo-Xiang;TuShu-Jie;Liushun-Cheng(DepartmentofChemist?..  相似文献   

3.
通过1H NMR, ESI-MS, 紫外-可见光谱等分析手段研究了两个新的质子化联吡啶盐客体与冠醚二苯并-24-冠-8在溶液中和气态下的包合行为. 研究结果表明, 质子化的联吡啶盐与冠醚主要形成1∶1的超分子包合物, 且存在夹心式的几何结构, 双质子化的联吡啶盐比单质子化的联吡啶盐具有更强的结合冠醚的能力, 其缔合常数分别为200, 116 L•mol-1.  相似文献   

4.
Sodium salicylate (NaSal where Sal=2-hydroxybenzoate), when mixed with dibenzo-24-crown-8 (DB24C8) yields a bimetallic complex [NaSal]2DB24C8 in most polar organic media, while potassium salicylate (KSal) under similar conditions shows a tendency to yield 11 or 21 complexes depending upon medium or synthesis. However, the presence of both NaSal and KSal together results in a unique mixed cation complex of composition NaKSal2DB24C8. This product melts sharply (190-92°C) without decomposition, displays IR spectral characteristics comparable to those of [Na(Sal)]2DB24C8, and is stable in aqueous media as shown by the detectable cation effect on the UV absorption bands of Sal and DB24C8. Single crystal X-ray analysis of NaK(Sal)2DB24C8 reveals that the system represents a co-crystallization complex of individual (KSal)2DB24C8 and (NaSal)2DB24C8 molecules. The crystals are monoclinic,P21/c,a=19.976(2) Å,b=9.031(1) Å,c=25.541(5) Å,=122.065(9)°, Å3,T=298 K,Z=2+2, CuK =1.5418 Å, and 2 (2.5°–100°). FinalR factor for the 3012 observed reflections (F>3) is 0.092. Both the Na2- and K2-molecules possess crystallographic centers of symmetry with one metal and its associated anion on each side of the crown ring. However, the conformations of the crowns are very different in the two molecules, with the K2-crown being nearly planar and the Na2-crown being quite puckered. Four oxygen atoms from the DB24C8 (KO, 2.680–2.908 Å) and three carboxyl oxygen atoms (KO, 2.472–2.708 Å) from separate salicylate ions coordinate with each potassium. Three oxygens from the crown (NaO, 2.536–2.65 Å) and three carboxyl oxygens (NaO, 2.31–2.563 Å) coordinate with each sodium. The salicylate ions lie on opposite sides and nearly perpendicular (77.2°, Na2-molecule; 82.7° K2-molecule) to each crown but coordinate to both of the metal ions within a molecule. The K+K+ and Na+Na+ distances in the respective molecules are 3.95 and 3.34 Å. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82044 (18 pages).  相似文献   

5.
在Pd(PPh3)4催化下,将单体(S)-6,6'-二溴-2,2'-二正丁氧基-1,1'-联萘[(S)-M-1]和(R)-6,6'-二溴-2,2'-二正丁氧基-1,1'-联萘[(R)-M-1]分别与2,5-二(4-三正丁基锡基苯)-1,3,4-噁二唑(M-2)通过Stille交叉耦合反应合成了手性高分子P-1与P-2,并用1HNMR、13CNMR、FTIR、UV、热分析、荧光光谱、GPC和CD等分析方法进行了表征.手性高分子P-1和P-2都能发射较强的蓝色荧光;在高分子侧链上引入丁氧基后使得手性高分子的溶解性能增强,并具有良好的成膜性能;在高分子主链引入亲电子的噁二唑生色团能使其特别适合于作为空穴电子传输层,对氧和热特别稳定,是一类潜在的光电高分子材料.  相似文献   

6.
江贵长  官文超  郑启新 《应用化学》2003,20(11):1044-1047
纳米微球;富勒烯-苯乙烯-甲基丙烯酸三元共聚物的合成及其摩擦学性能  相似文献   

7.
Five new bis(benzo-15-crown-5) derivatives with different connecting groups were synthesized. Potassium ion-selective PVC membrane electrodes based on these bis(crown ether)s were prepared and their selective properties were measured. The results showed that most of these electrodes are stable over a wide pH range and their selectivity coefficients were better than those of an electrode based on natural valinomycin.  相似文献   

8.
苯乙烯/马来酸酐共聚物智能水凝胶的制备与性能   总被引:3,自引:0,他引:3  
合成了苯乙烯/马来酸酐共聚物接枝聚乙二醇400(PEG400)水凝胶.研究了环境pH、温度、离子强度对该凝胶溶涨性能的影响,并对凝胶的动态溶涨行为进行了分析.结果显示该水凝胶对环境pH、温度、离子强度等变化均作出体积相转变响应,表现出了智能高分子凝胶的特性.  相似文献   

9.
Interaction of hydrated protons (HPs) with dibenzo-24-crown-8 (DBC in nitrobenzene-d(5) was studied by (1)H and (13)C NMR under assistance of ab initio-density functional theory (DFT) quantum calculations. HPs were afforded by hydrogen bis(1,2-dicarbollyl) cobaltate (HDCC) with 3.5 M excess of H(2)O. The forming of a complex between HP and DBC leads to marked and additive relative shifts of both (1)H and (13)C signals. This was utilized for the estimation of the stabilization constant K of the complex. Its value is at least 10(6) l/mol, which agrees with the result of independent extraction method (log K = 6.3). Using absolute integral intensities of the HP signal in a water-saturated system, it was shown that the form of HP present in the complex must be H(5)O(2)(+), in accord with formerly published structure of the complex in crystalline form. The investigation of the dynamics of exchange between bound and free DBC by transverse relaxation using variably spaced pulses in the Carr-Purcell-Meiboom-Gill (CPMG) sequence or on-resonance rotating-frame relaxation with variable spin-lock field intensity was partly hampered by the fast relaxation of some signals in the complex because of relative immobilization of its internal motions. In order to remove these effects, a pulse sequence dipolar interaction-free transverse relaxation (DIFTRE) for static DIFTRE was devised and the MLEV17 pulse sequence with high intensity of electromagnetic field was used in a separate series of experiments. Using the results of these latter experiments, the correlation time of exchange was established to be about 0.8 ms, which complied with the shape of the spectra. The accompanying ab initio DFT calculations showed that the apparent symmetry of the molecules of both DBC and its complex with H(5)O(2)(+) was probably the result of averaging of energetically close conformations (five for DBC and four for the complex). Both NMR and the calculations show that the basic mode of binding of the ion in the complex is analogous to that found in crystal but the most pronounced conformation is slightly different.  相似文献   

10.
Two novel 25,27-dihydroxy-26,28-bis(3-phenylthiapropxy)-calix[4]arene(3) and 25,27-dihydroxy-26,28-bis(3-phenylthiapropoxy)-5,11,17,23-tetra-tert-butylcalix[4] arene (4) were synthesized for the evaluation of their ion-selectivity in ion-selective electrodes(ISEs).ISEs based on 3 and 4 as neutral ionophores were prepared,and their selectivity coefficients for Ag^ (lg KAg,M^pot)were investigated against other alkali metal,alkaline-earth metal,aluminum,thallium(Ⅰ),Lead and some transition metal ions using the separate solution method (SSM).These ISEs showed excellent Ag^ seletivity over most of the interfering cations examined,except for Hg^2 and Fe^2 having relative smaller interference(lg KAg,M^pot≤-2.1).  相似文献   

11.
Tetra-N-substituted 1,10-dioxa-4,7,13,16-tetraazacyclooctadecanes (tetraazacrown ethers) (1-5) have been synthesised. Each compound was incorporated in a PVC membrane that provided the basis for a lead-selective potentiometric electrode. The electrode based on the 4,7,13,16-tetrathenoyl-1,10-dioxa-4,7,13,16- tetraazacyclooctadecane (5) ionophore bearing four thenoyl functional subunits exhibited excellent lead (II) ion selectivity with only Ag+ and Hg2+ significantly interfering. The crystal structure of this host (5) has been determined by single crystal X-ray analysis. Crystal data. C32H36N4O6S4, M 700.9, monoclinic, space group P21/c, a, 10.315(4), b, 13.635(2), c, 14.357(6)Å, 124.63(2)°, V 1661.6(9)Å3, Dc 1.40 g cm-3, Z 2, Cu 29.90 cm-1. Final residuals R, Rw were 0.054, 0.082 for the observed data.  相似文献   

12.
A conductance study concerning the association of Na+, K+, Rb+, and Cs+ with 1,13-dibenzo-24-crown-8 in acetonitrile has been carried out at 35, 30, 25, 20, and 15°C. The observed molar conductivities were found to decrease significantly for mole ratios less than unity. A model involving 11 stoichiometry has been used to analyze the conductivity data. The stability constant, K, and the molar conductivity C for each 11 complex were determined from the conductivity data by using a nonlinear least squares curve fitting procedure. The binding sequence, based on the value of log K at 25°C, is found to be Rb+>Cs+>K+>Na+. Values of Ho and So are reported and their significance is discussed.  相似文献   

13.
New derivatives of dibenzo-24-crown-8-dicarboxylic acid diamide with salsoline, salsolidine, and anabasine moieties were prepared by condensation of the alkaloids with 4′,4″(5″)-dibenzo-24-crown-8-dicarboxylic acid dichloride. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 471–473, September–October, 2006.  相似文献   

14.
从内聚能的角度建立了含共聚组成、序列不均匀性的共聚物分子量及分布理论,导出其计算式.将凝胶渗透色谱(GPC)与紫外吸收光谱(UV)和示差折光仪(DR)串接,测定苯乙烯(St)/N-苯基马来酰亚胺(PMI)共聚物的分子量.根据St/PMI共聚合原理,对St-PMI共聚物的分子量进行模型化,该模型能较好地预测引发剂、单体配比、转化率对共聚物分子量的影响.  相似文献   

15.
夏敏  卢跃东 《合成化学》2005,13(1):29-32
以具有热敏性能的N-异丙基丙烯酰胺及其衍生物的共聚物作载体,利用温度为相分离的控制手段,在水介质中合成了2-氨基-3-氰基-4-取代苯基-5-甲氧羰基-4H-喃化合物,其结构经^1H NMR,IR和元素分析确证。  相似文献   

16.
以水合肼和2-甲酰基-8-乙氧羰甲氧基喹啉为原料合成了希夫碱双(8-乙氧羰甲氧基-2-亚甲喹啉基)缩连氮(BEQA),经1HNMR、元素分析等进行了结构表征,在乙醇-水混合溶剂中采用UV-Vis光谱法研究了H+、Ca2+、Mg2+、Sr2+、Mn2+、Co2+、Ni2+、Cu2+、Zn2+、Cd2+及Hg2+对BEQA光谱的影响,结果表明,BEQA分子的UV-Vis光谱仅对体系中的H+、Cu2+和Cd2+有特殊的选择传感性,在体系中的pH值或Cu2+、Cd2+浓度增大时,BEQA在380 nm处的吸收峰强度会逐渐减小,并伴随有不同程度的蓝移;Job′s法测定Cu2+和Cd2+与BEQA形成配合物的化学计量比为1∶4。  相似文献   

17.
A novel fuUerene-acrylamide copolymer was synthesized via radical polymerization. It is soluble in polar solvents such as water, dimethyl sulfoxide etc. The product was characterized by FTIR, UV-Vis and GPC. TEM analysis shows that the average particle diameter is about 46 nm. Four-ball tests show that the addition of a certain concentration of the fullerene copolymer to base stock (2 wt% triethanolamine and 0.5 wt% OPZ aqueous solution) can effectively raise the load-carrying capacity (PB value) and the antiwear ability. SEM analysis shows that the addition results in reducing diameter of wear scar and decreasing wear.  相似文献   

18.
用手性α-氨基醇和原氯乙酸三乙酯作用得到的手性恶唑啉2a-2c和1,7-二氯- 12-冠-4反应,合成了带手性侧链的1,7-二氯-12-冠-4衍生物1a-1c,并将其铜配 合物运用于重氮醋酸酯对烯烃的不对称环丙烷化反应.  相似文献   

19.
以2-溴代异丁酸乙酯(EBiB)为引发剂,CuBr/CuBr2/1,10-邻二氮菲(phen)为复合催化剂,十二烷基磺酸钠(SLS)为乳化剂,考察了水分散体系中苯乙烯(St)和甲基丙烯酸甲酯(MMA)的原子转移自由基共聚合的可控性和相对反应活性.在此基础上,通过反应进料法在水分散体系中进行了St和MMA的梯度共聚合,反应表现出“活性”聚合的特征,即所得共聚物的数均分子量随着单体转化率的增加而增大,分子量分布较窄(Mw/Mn<1.50).用1HNMR跟踪分析了聚合反应过程中共聚物微观组成的变化规律,结果表明,共聚物链中MMA链节的累积含量和瞬时含量都随着共聚物相对链长的增加而增加,即随着聚合物相对链长的增加共聚物的微观组成从St链节占主导地位逐渐变化为以MMA链节占主导地位,表明确实形成了St和MMA的梯度或渐变共聚物.  相似文献   

20.
通过可逆加成-裂解链转移聚合和原子转移自由基聚合,制备了以聚丙烯酸叔丁酯为主链、以聚(聚乙二醇单甲醚甲基丙烯酸酯)为侧链的两亲性接枝共聚物PtBA-g-PPEGMEMA,该方法克服了以往通过聚合物修饰来引入接枝点时所存在的接枝点密度不高和不可控的局限性.接着,以PtBA-g-PPEGMEMA为载体,对抗肿瘤药物阿霉素进行了负载,制备得到了尺寸为164.8nm的纳米载药胶束.其释放试验表明,该体系具有缓释特征.  相似文献   

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