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1.
以N-乙酰-L-酪氨酸乙酯为原料,与6个取代芳胺重氮盐在碱性条件下发生偶合反应,合成了6个新型的N-乙酰-L-酪氨酸乙酯偶氮衍生物,结构通过IR、~1H NMR进行了表征.探讨了所合成化合物的偶氮式-腙式互变异构以及溶剂和pH对紫外可见光谱的影响.结果表明,溶质-溶剂相互作用会影响化合物在不同溶剂的λmax发生微小的变化,分子内和分子间氢键的作用影响较大.溶液pH会直接影响偶氮式-腙式的平衡构成,随着pH的增加,腙式在偶氮-腙互变异构平衡中的比例逐渐增加.这些偶氮化合物有望成为一类潜在的pH指示剂.  相似文献   

2.
本工作合成了数种带不同取代苯基的羟基喹啉偶氮类化合物。对它们在不同溶剂。不同酸碱度溶液中的偶氮式及腙式间互变异构平衡进行了研究。苯环上不同取代基的引入可引起平衡发生变化。拉电子基的引入有利于腙式结构的形成,而推电子基的引入则对偶氮的生成影响不大。此外,工作中还发现:羟基喹啉偶氮化合物在光照下存在着以偶氮顺-反异构化反应为主的变化过程。  相似文献   

3.
以对叔丁基杯[4]芳烃为原料,经过取代、缩合等多步反应,合成了5个下缘同时含有偶氮和亚氨基团的新型杯[4]芳烃衍生物,其结构经IR、1H NMR、13C NMR和元素分析进行了表征.并通过UV/Vis光谱研究了其对金属离子的识别作用.结果发现化合物25,27-二羟基-26,28-二{2-[2-(N-(4-苯偶氮基-1-萘基)亚氨基次甲基)苯氧基]乙氧基}对叔丁基杯[4]芳烃(4c)对Al3+和Sn2+有较好的识别作用,而化合物25,27-二羟基-26,28-二{2-[2-(N-(4-(4-甲基苯偶氮基)-1-萘基)亚氨基次甲基)苯氧基]乙氧基}对叔丁基杯[4]芳烃(4e)可以专一性地识别Al3+,其与Al3+络合的物质的量比为1∶1.  相似文献   

4.
以2-氨基噻唑为原料,经重氮化-偶联反应合成了5,11,17,23-四(2-噻唑)偶氮基-25,26,27,28-四羟基杯[4]芳烃和5,11,17,23,29,35-六(2-噻唑)偶氮基-37,38,39,40,41,42-六羟基杯[6]芳烃,产物的结构经IR,^1H NMR和元素分析表征;研究了它们的光谱性能和对金属离子的识别状况,发现在pH=7.2的Tris介质中对Ag^ 和Hg^2 等有较好的光谱变化识别。  相似文献   

5.
新型偶氮化合物的合成及其光学性质   总被引:1,自引:0,他引:1  
以咔唑和苯酚为原料,经重氮和偶合反应合成了一种新型偶氮化合物--N-对(4-羟基苯偶氮基)苯基-3,6-二(叔丁基)咔唑(4),其结构经1H NMR和13C NMR表征.4的 UV和固体荧光光谱研究结果表明,4具有较好的光学活性.  相似文献   

6.
农兰平  肖成梁  刘运海  彭杰  张安运 《合成化学》2011,19(4):538-541,549
在乙腈中,25,26,27,28.四羟基杯[4]芳烃(1)与碘代异丙烷(i-PrI)在碳酸钾的催化下经双烷基化反应合成了25,27-二异丙氧基-26,28-二羟基杯[4]芳烃(2),其结构经<'1>H NMR和MS确证.最佳反应条件为:1 23mmol,n(1):n(K<,2>CO<,3>):n(i-PrI):n(Me...  相似文献   

7.
含咔唑和偶氮苯的乙炔衍生物的合成   总被引:1,自引:0,他引:1  
采用Sonagashira偶联反应和N-烷基化反应合成了含有咔唑和偶氮苯的乙炔衍生物:3-乙炔基-9-(4-[4-(硝基)苯基偶氮苯]氧)亚丁基咔唑3.其结构通过IR,1H NMR,13C NMR,元素分析和X-射线单晶衍射法测定.标题化合物属单斜晶系,P21/c空间群;a=9.238(3),b=28.240(8),c...  相似文献   

8.
颜景辉  汤又文 《合成化学》2004,12(4):323-324,J001
以对叔丁基苯酚为起始原料,通过缩合、取代反应合成了25,26,27,28-四对-乙酰胺苯磺酰氧基对叔丁基杯[4]芳烃,其结构经FT—IR,^1H NMR和FAB-MS表征。  相似文献   

9.
在微量O2存在时,酮腙与NO发生偶氮-硝化反应,高选择性地生成了α-硝基偶氮化合物.产物结构经NMR,IR,MS,HR-ESI-MS和X射线单晶衍射等技术确证.通过高效液相色谱对反应体系中不同O2含量(空气)下的产物组成进行分析,结果表明体系中O2含量的控制对α-硝基偶氮化合物的生成反应的选择性有较大影响.  相似文献   

10.
3,3′-偶氮-(6-氨基-1,2,4,5-四嗪)的合成与表征   总被引:1,自引:0,他引:1  
以硝酸胍和水合肼为原料,经7步反应合成了高氮含能化合物3,3′-偶氮-(6-氨基-1,2,4,5-四嗪),其结构经1H NMR,13C NMR,IR及元素分析表征。  相似文献   

11.
This article describes the synthesis, structure andUV properties of azocalixcrowns in which the photoresponsivetrans-cis azo benzene unit has been introduced in the glycolicchains of the calix[4]crowns. The synthesis proceeded via the selective-1,3O-dialkylation of calix[4]arene with glycolic chains terminated bynitrophenyl residues. After reduction of thenitro groups into amino functions,intramolecular oxidative coupling produced thecapping of the calixarene. Thesynthetic approaches and the cis-transstructure of these new ligandsare discussed and full details on synthesesand structural data are given. Apreliminary example of cesium complexation byone of the ligands is proposed.  相似文献   

12.
Thiacalix[4]arenes bearing two or four carboxylic functions on the lower rim served as starting compounds for the synthesis of novel calixarene oligomers connected by amidic functions. The cone conformers react smoothly with four molecules of 5-amino-calix[4]arene to yield the corresponding pentakis-calixarenes. On the other hand, because steric hindrance, the 1,3-alternate condenses only with two molecules leading thus to tris-calixarene, possessing a novel type of inherent chirality based on the 25,26-substitution pattern. The title compounds, which connect together ‘classical’ calixarene and thiacalixarene building blocks, represent a first step towards calixarene-based dendritic structures.  相似文献   

13.
New photoreactive calixarene derivatives containing spiro ortho ester groups (calixarenes 3a–3c ) were synthesized by the reaction of 2‐bromomethyl‐1,4,6‐trioxaspiro[4.4]nonane with 2,8,14,20‐tetramethyl‐4,6,10,12,16,18,22,24‐octakis(carboxymethoxy)calix[4]resorcinarene, 5,11,17,23,29,35‐hexamethyl‐37,38,39,40,41,42‐hexakis(carboxymethoxy)calix[6]arene, and 5,11,17,23,29,35,41,47‐octa‐tert‐butyl‐49,50,51,52, 53,54,55,56‐octakis‐(carboxymethoxy)calix[8]arene, which were prepared by the reaction of C‐methylcalix[4]resorcinarene, p‐methylcalix[6]arene, and ptert‐butylcalix[8]arene, respectively. The thermal stability of the obtained calixarene derivatives containing spiro ortho ester groups was examined with thermogravimetric analysis, and it was found that these calixarene derivatives had good thermal stability. The photoinitiated cationic polymerization of spiro ortho ester groups in calixarene derivatives 3a–3c was examined with certain photoacid generators in the film state. Interestingly enough, the reaction of calixarene derivatives did not proceed with only photoirradiation; however, the reaction proceeded smoothly when the photoirradiation was followed by heating. Furthermore, calixarene 3a , composed of a C‐methylcalix[4]resorcinarene structure, showed the highest photochemical reactivity in this reaction system. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1293–1302, 2002  相似文献   

14.
5,11,17,23‐Tetra‐tert‐butyl‐25,26,27,28‐tetrahydroxycalix[4]arene and 25,26,27,28‐tetrahydroxycalix[4]arene were synthesized based on previous literature. Firstly, several azo dyes were synthesized, and then, these dyestuffs were chlorinated through reaction with thionyl chloride. Secondly, the azo compounds bonded with methylene chloride and reacted with 25,26,27,28‐tetrahydroxycalix[4]arene, and then, six novel disazocalix[4]arene derivatives 4 ( a – f ) were achieved. Their structures were characterized as Fourier transform infrared, 1H‐NMR, and elemental analysis. In this study, we investigated the solvatochromic properties of the compounds and the acid–base effect on their ultraviolet–visible absorption by using six solvents.  相似文献   

15.
Synthesis of new calix[4]resorcinol molecules with acetal groups on the upper rim associated with calixarene skeleton through γ-aminoalkyl spacers was performed. The condensation of the compounds studied with 2-methylresorcinol was studied.  相似文献   

16.
通过对杯[4]芳烃以及杯[6]芳烃上缘进行烯丙基化和硅氢加成2步衍生化反应得到硅氢化杯[4]芳烃以及硅氢化杯[6]芳烃,再将这2种硅氢化杯芳烃衍生物分别接枝到超细SiO2上。在不同的pH值条件下,就2种杯芳烃接枝超细SiO2衍生物对水合Cu2+及Ag+的萃取性能进行了研究。结果表明,与对叔丁基杯芳烃相比较,杯芳烃接枝超细SiO2衍生物对Cu2+和Ag+的萃取率都有所提高,其中杯[4]芳烃接枝超细SiO2对Ag+的最高萃取率达到98.78%,杯[6]芳烃接枝超细SiO2对Cu2+的最高萃取率达到67.74%。  相似文献   

17.
采用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)对杯芳烃化合物进行了分析。探讨了样品的制备条件、仪器操作参数等因素对测定结果的影响。25种样品的质谱数据表明,利用MALDI-TOF-MS可非常方便地得到灵敏度、分辨率、准确度均较高,且易于识别和解析的质谱图,为此类化合物的质谱表征提供和建立了一种新的高效分析方法。  相似文献   

18.
The synthesis of the new heterocycles, 4-amino[1]benzofuro[3,2-g]cinnolines, was accomplished by the intramolecular cyclization of the Z -configuration of cyanoarylhydrazones. The latter compounds were obtained via interaction between the diazonium salt of 3-amino-dibenzofuran and various active methylene compounds via the Japp-Klingemann reaction. The alkaline treatment of azo intermediates 4 , which may be isolated in the course of condensation, gave the corresponding cyanoarylhydrazones 5 . A study of the configuration and possible isomerisations is reported.  相似文献   

19.
We report a series of calix[4]arene Mo(VI) dioxo complexes M2RC4MoO2 (M = alkali metal, R = H or Bu(t)) that were fully characterized by NMR, X-ray, IR, UV/vis, and elemental analysis. Molybdocalix[4]arene structures can be controlled via lower rim deprotonation, groups at para positions of calix[4]arene, and alkali metal counterions. Mono deprotonation at the lower rim leads to calix[4]arene Mo(VI) monooxo complexes RC4MoO (R = H, Bu(t), or allyl), and full deprotonation gives rise to calix[4]arene Mo(VI) dioxo complexes. Structural studies indicate that HC4 Mo(VI) dioxo complexes easily form polymeric structures via cation-pi interaction and coordination between different calixarene units. However, Bu(t)C4 Mo(VI) dioxo complexes tend to form dimers or tetramers due to steric hindrance of the tert-butyl groups at para positions in calixarene. The structures of the reduced side products A and C were determined by X-ray diffraction studies. The mechanism of RC4MoO formation from the reaction of calixarene monoanions with MoO2Cl2 appears to include the addition of a calixarene -OH group across a Mo=O bond.  相似文献   

20.
Classical molecular dynamics simulations were used to study p-tert-butylcalix[4]arene inclusion compounds with xenon, nitrogen, hydrogen, methane, and sulfur dioxide guest molecules. The calixarene units were taken to be rigid and the intermolecular molecular interactions were modeled as a sum of the van der Waals interactions with parameters from the AMBER force field and electrostatic interactions. Simulations of the high-density alpha phase and low-density beta0 phase of p-tert-butylcalix[4]arene were used to test the force field. The predicted densities of the two phases were found to agree with experimental measurements at 173 K to within 5 %. Simulations were performed with guests placed inside the calixarene cages of the beta0 phase. Guest-host ratios of 1:1 to 1:4 were considered. Changes in the unit-cell volume and density of the phases with the addition of guest molecules and the inclusion energies for the guests were determined. Finally, the dynamics of the guest motion inside the cages were characterized by determining the root-mean-square displacements and velocity autocorrelation functions of the xenon and nitrogen guests.  相似文献   

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