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1.
硫、硒杯[4]芳烃萃取银   总被引:4,自引:0,他引:4  
陈朗星  居红芳  何锡文 《分析化学》2001,29(12):1443-1446
以5,11,17,23-四(1,1-二甲基乙基)-25,27-二羟基-26,28-二[(2-乙基硫)乙氧基]杯[4]芳烃(1)和5,11,17,23-四(1,1-二甲基乙基)-25,27-二羟-26,28-二[(2-乙基硒)]乙氧基杯[4]芳烃(2)为萃取剂,研究了在弱酸性条件下杯芳烃衍生物与银的络合行为。杯芳烃衍生物与银形成1:1萃取络合物,在大量碱金属、碱土金属、常见过渡金属离子存在下,对银离子有很高的萃取率和选择性。  相似文献   

2.
曾昭睿  王建玲 《分析化学》1998,26(9):1060-1064
合成了两种新型的杯(4)芳烃衍生物:5-1′,1′-二甲基十一烯氧基苯基甲基-11,17,23-三-1,1-二甲基乙基-25,26,27,28-四苄氧基杯(4)芳烃C(4)TB)及5-1′,1′-二甲基十一烯氧基苯基甲基-11,17,23-三-1′,1′-二甲基-25,26,27,28-四乙氧羰甲氧基(C(4)TECM)其结构经元素分析IR,^1HNMR,MS的数据证实,分别将其与OV-1701固  相似文献   

3.
N-(N’,N’-二甲基氨基乙基)-4-硝基-1,8-萘酰亚胺和2,3-二甲基苯并噻唑碘化盐在痕量水存在下经亲核取代反应合成了一个新型的萘酰亚胺衍生物——N-(N’,N’-二甲基氨基乙基)-4-[2-(2,3-二氢-2,3-二甲基苯并噻唑)氧基]-1,8-萘酰亚胺,其结构经1H NMR,13C NMR和ESI-MS表征。并对反应机理进行了初步研究。  相似文献   

4.
我们以1,4-二正丙氧基-2,5-双甲氧甲基苯为原料用对甲苯磺酸为催化剂在二氯甲烷中制备了1,4-双正丙氧基柱[5]芳烃, 1,4-双正丙氧基柱[6]芳烃和1,4-双正丙氧基柱[7]芳烃. 我们用氢谱, 碳谱和质谱对它们进行了表征. 它们有不同的氢谱却有相似的碳谱. 对比它们的空腔尺寸, 柱[5]的内径大约是4.6 Å, 与葫芦脲[6]及α-环糊精类似. 柱[6]的内径大约是6.7 Å, 与葫芦脲[7]及β-环糊精类似. 柱[7]的内径大约是8.7 Å, 与葫芦脲[8]及γ-环糊精类似. 我们用正辛基三乙基六氟磷酸铵盐作为模型客体研究了它们之间的主客体络合. 柱[5]与之有微弱的络合, 柱[6]显示了良好的络合, 而柱[7]与之没有络合.  相似文献   

5.
以甲基丙烯酸-N,N-二甲基氨基乙酯为亲核试剂,分别与4-溴甲基二苯甲酮和4,4’-二(溴甲基)二苯甲酮在20℃下反应,并过简单的过滤,得到了两种水性可聚合二苯甲酮类光引发剂:4-[N-(2-甲基丙烯酰氧基乙基)二甲基溴化铵甲基]二苯甲酮(收率79.2%)和4,4’-双[N-(2-甲基丙烯酰氧基乙基)二甲基溴化铵甲基]二苯甲酮(收率79.7%)。产物用NMR、IR和元素分析进行了表征。  相似文献   

6.
以对苯二甲醛、乙酸酐为原料合成对苯二甲醛单缩醛, 接着与间苯二酚反应, 制备了含醛基杯[4]芳烯. 利用季戊四醇与含醛基杯[4]芳烯反应, 进而再与3-[4-(2,5-二氧杂环戊基)苯基]-9-[4-二(甲羰氧基)甲基苯基]-2,4,8,10-四氧杂螺环[5.5]十一烷反应, 合成了杯[4]芳烯星形化合物, 收率为65.2%. 产品结构经 IR, 1H NMR, MS 和元素分析进行了表征.  相似文献   

7.
研究了三种不同长度碳链取代的半菁类染料2-[4-(N,N-二羧乙基)氨基]苯乙烯基-1,3,3-三甲基苯并吲哚鎓碘(BIDC1)、2-[4-(N,N-二羧乙基)氨基]苯乙烯基-1-丁基-3,3-二甲基苯并吲哚鎓碘(BIDC2)和2-[4-(N,N-二羧乙基)氨基]苯乙烯基-1-辛基-3,3-二甲基苯并吲哚鎓碘(BIDC3)敏化太阳能电池的光电化学性能。其中BIDC1的敏化效果最好,在100mW/cm2氙灯光源下,开路电压、短路电流、填充因子和转换效率分别是430mV、1.31mA/cm2、0.52、0.29%。研究表明,随着半菁染料碳链取代基的增长,光电转换效率逐渐降低。  相似文献   

8.
具有阳离子表面活性ATRP引发剂的合成   总被引:1,自引:1,他引:0  
以2-溴异丁酰溴、2-溴乙醇、6-氯-1-己醇及N,N-二甲基正十二烷基胺为主要原料,分别通过两步或三步反应合成了具有阳离子表面活性的原子转移自由基聚合(ATRP)引发剂——N-[2-(2-溴-2-甲基丙酰氧基)乙基]-N,N-二甲基正十二烷基溴化铵或N-[6-(2-溴-2-甲基丙酰氧基)己基]-N,N-二甲基正十二烷基碘化铵,其结构经1H NMR,13C NMR,IR和元素分析表征。  相似文献   

9.
姚其正 《有机化学》2002,22(8):555-559
用N,N-二甲基甲酰胺缩二甲醇[(CH3)2NCH(OCH3)2,1]和蝶呤(2-氨基-4- 羟基蝶啶)衍生物在极性有机溶剂中反应一般得到脒化产物:N^2-(N,N-二甲基氨 基亚甲基)-蝶呤衍生物,但是在1,4-二氧六环中进行以上反应时发现,N,N-二甲 基酰胺缩二甲醇(1)不仅是脒化试剂,而且也是蝶呤化合物的甲基化试剂,并且 也依据蝶呤的N^2-位的不同取代基进行选择性的N(3)-或O^4-甲基化反应。  相似文献   

10.
分子识别是生物识别的基础,其机理的研究对理解生命现象具有重要意义。水溶性杯芳烃是研究分子识别的重要主体分子,本实验报道合成了水溶性的5,11,17,23,29,35,41,47-八(N,N-二甲氨甲基)-杯[8]芳烃(以下简称杯胺),采用荧光法测定了其与二苯胺磺酸钠的包结常数,研究了包结作用。以杯胺为流动相添加剂,二苯胺磺酸钠为溶质,采用色谱法进行了对比研究,结论相符。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

13.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

14.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

15.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

16.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

17.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

18.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

19.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

20.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

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