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1.
通过向杯[4]芳烃下沿引入不同基团,合成得到四种杯[4]芳烃衍生物(2,3,4和5),并采用NMR、ESI-MS和EA对所合成的化合物进行结构表征.同时培养得到化合物2,3和4的单晶,解析出晶体结构,发现在化合物3和4的晶体中同时存在杯[4]芳烃的两种主要构象:锥型和部分锥型.通过分析研究,把产生这种现象的原因归结为:当下沿的保护基团具有适度大的尺寸时,就能够阻止苯环的翻转,并且提供足够的空间.当杯芳烃从溶液中析出时,第四个苯环随机地定位,从而使得两种构象并存于同一晶体中.  相似文献   

2.
杯[4]芳烃与1,2-二溴乙烷反应合成1,3-二溴乙氧基杯[4]芳烃衍生物(化合物1),化合物1分别与乙醇胺和S-(+)-4-甲基-2-氨基-1-戊醇反应,较高产率地合成了含氨基醇片段的杯[4]芳烃衍生物(化合物2)和含手性氨基醇片段杯[4]芳烃衍生物(化合物3).新化合物的结构经元素分析、1HNMR和ESI-MS等表征证实,其结构为1,3-二取代模式且为锥式构象.  相似文献   

3.
A modified PTC method of preparing tetra-O-alkylated calix[4]arenes is described. Using PEG-400 as phase-transfer catalyst and solid sodium hydrate as a base, full alkylation of calix[4]arenes has been proceeded smoothly in toluene at 90°C. The debutylated calix[4]arene can also be fully alkylated by this method. Supported by the National Natural Science Foundation of China Hu Xubo: born in 1965, Ph. D. Graduate student  相似文献   

4.
New polyimide containing calix [4] arene moieties on the polymer backbone was successfully synthesized in N- methy1 - 2 - pyrrolidone (NMP) by polycondensations of 3, 3', 4, 4'- oxydiphthalic anhydride (ODPA) with the diaminocalix[4]arene monomer using 3,3'- dimethy1- 4, 4'- The polyimide prepared is soluble in common solvents, such as NMP, DMAc, DMF and chloroform. The polyimide films obtained have excellent thermal stability and mechanical property. At the same time, the liquid membrane transport of potassium ions by the new polyimide was investigated, which testified that compared to ODPA-DADPM polyimide, the polyimide containing culix[4] arenes has the transport ability to metal ions in regard to bulky, cone-like calix [-4] arene moieties.  相似文献   

5.
杯[4]芳烃与过量氯乙酸乙酯反应,得到杯[4]芳烃四酯基衍生物2.化合物2与水合肼反应得到杯[4]四酰肼衍生物3,化合物3进一步与异硫氰酸苯酯反应得到四取代杯[4]芳烃酰胺基硫脲衍生物4.反应处理简便,总产率为71%.新化合物的结构经红外光谱、核磁共振氢谱和质谱表征.阳离子萃取实验表明,化合物4不仅对软硬金属离子均有较好的萃取性能,而且对Na 和Ag 有一定的选择性配合能力.  相似文献   

6.
王建玲  候学会  王国庆  吕全建 《河南科学》2011,29(11):1305-1308
将双十一碳烯氧基杯[4]芳烃冠醚聚硅氧烷(C[4]C5-PSO)和上缘稀基取代杯[4]芳烃四苄基醚聚硅氧烷(C[4]TBE-PSO)用作毛细管气相色谱固定相,通过测定一些芳香族位置异构体在2种固定相上的热力学参数△H、△S和△G,探讨了杯[4]芳烃衍生物气相色谱固定相对芳香族位置异构体分子识别的特性和保留机理.  相似文献   

7.
Prins LJ  De Jong F  Timmerman P  Reinhoudt DN 《Nature》2000,408(6809):181-184
Chiral molecules have asymmetric arrangements of atoms, forming structures that are non-superposable mirror images of each other. Specific mirror images ('enantiomers') may be obtained either from enantiomerically pure precursor compounds, through enantioselective synthesis, or by resolution of so-called racemic mixtures of opposite enantiomers, provided that racemization (the spontaneous interconversion of enantiomers) is sufficiently slow. Non-covalent assemblies can similarly adopt chiral supramolecular structures, and if they are held together by relatively strong interactions, such as metal coordination, methods analogous to those used to obtain chiral molecules yield enantiomerically pure non-covalent products. But the resolution of assemblies formed through weak interactions, such as hydrogen-bonding, remains challenging, reflecting their lower stability and significantly higher susceptibility to racemization. Here we report the design of supramolecular structures from achiral calix[4]arene dimelamines and cyanurates, which form multiple cooperative hydrogen bonds that together provide sufficient stability to allow the isolation of enantiomerically pure assemblies. Our design strategy is based on a non-covalent 'chiral memory' concept, whereby we first use chiral barbiturates to induce the supramolecular chirality in a hydrogen-bonded assembly, and then substitute them by achiral cyanurates. The stability of the resultant chiral assemblies in benzene, a non-polar solvent not competing for hydrogen bonds, is manifested by a half-life to racemization of more than four days at room temperature.  相似文献   

8.
Two new tetraamides bridged calix[4]arenes were synthesized by the condensation reaction of 1,3-bis-chlorocarbonylmethyl p-tert-butylcalix[4]arene with 1,2-bis (2′-amino-2′-methylpropanamido) benzene or 1,2-bis (2′-amino-2′-methylpropanamido)-4,5-dichloro benzene, respectively. The new compounds were characterized by1H-NMR, MS-FAB, and elemental analysis; macrocyclic polyamine. Foundation item: Supported by the National Science Foundation of China (20072029) Biography: Xiao Yuan-jing (1974-), male, Doctor, research direction: supramolecular chemistry.  相似文献   

9.
1 Results In this paper we report supramolecular polymeric nano networks formed by the molecular-recognition-directed self-assembly between a calix[5]arene and C60[1]. Covalently-linked double-calix[5]arenes take up C60 into their cavities[2]. This complementary interaction creates a strong non-covalent bonding; thus,the iterative self-assembly between dumbbell fullerene 1 and ditopic host 2 can produce the supramolecular polymer networks (See Fig.1).  相似文献   

10.
The inclusion properties of two calix[4]arene derivatives 5, 11, 17, 23-tetra-tert-butyl-25, 27-bis (isopropyl carbamoyl-methoxy)-26,28-diundecenyloxy calix[4]arene (C[4]A) and 25, 27-dibutoxy-5, 11, 17,23-tetra-tert-butyl-26,28-diundecenyloxy calix[4]arene (C[4]B) were studied by gas chromatographic method. It was found that C[4]A could form inclusion complexes with benzene, toluene, methanol and ethanol while C[4]B could only form inclusion complex with methanol, which might be due to the different conformations of C[4]A and C[4]B. Molecular modeling showed that CH/π and OH/π interactions played important roles in the forming of inclusion complexes. Biography: YU Xiao-dong (1973-), male, PhD candidate.  相似文献   

11.
对-甲基杯[4]芳烃激光光解的研究   总被引:2,自引:0,他引:2  
研究了对-甲基杯[4]芳烃在环己烷和乙腈中的激光光解行为,在环己烷中观察到4200nm及540nm附近的杯芳烃激发三线态吸收峰,极性溶剂乙腈对该三核态有稳定作用,吸收峰显著红移,其三线态双峰特征与不带取取代基的杯[4]芳烃相近,同时发现在330nm附近杯芳烃自由基吸收峰,其动力学分析表明,该自由基按二级动力学衰减。  相似文献   

12.
新型杯[4]芳烃衍生物的合成及结构表征   总被引:5,自引:0,他引:5  
为进一步研究杯[4]芳烃衍生物,并为后续衍生化反应制备中间体,用对叔丁基苯酚和甲醛为原料,利用一步法合成了对叔丁基杯[4]芳烃;再以对叔丁基杯[4]芳烃与碘乙醇的反应,得到了对叔丁基25,27-二羟基-26,28-二羟乙氧基杯[4]芳烃,其结构经1H NMR、13C NMR,、IR、MS和元素分析确证.  相似文献   

13.
6-4-(取代苯基)哒嗪酮类化合物具有较强的抑制血小板聚集作用。该文以乙酰苯胺为原料,经傅-克反应、水解反应及水合环合反应、溴化反应、N-烷基化反应等一系列反应合成了6-[4-[4-(取代苯乙酮基)哌嗪基]苯基]-4,5-二氢-3(2H)哒嗪酮类化合物,在N-烷基化中采用相转移催化,使收率大幅提高,并通过元素分析,^HNMR确证结构。  相似文献   

14.
本文合成了4-[(3,5-二异丁基-4-羟基苯)(3,5-二异丁基-4-苯醌基)甲基]苯乙炔单体(EPHG),由铑络合物和手性胺催化体系引发聚合,利用CD-UV谱图确认生成的聚合物是螺旋结构.讨论了聚合机理,调查了溶剂对聚合的影响,结果表明:在四氢呋喃溶液中,铑络合物[Rh(cod)Cl]2和(R)-苯乙基胺催化体系引发EPHG聚合成同一手性的螺旋聚合物,并且有较高的收率。  相似文献   

15.
根据成键原子的结构特征,提出了计算取代芳烃原子点价δi的新方法,并由δi建构了取代芳烃的分子连接性指数mXn,用mXn与取代芳烃对斜生栅列藻急性毒性,诱发浮萍萎黄病毒性、绿藻毒性、大型蚤毒性、斑马鱼毒性和金鱼毒性等6项生物活性相关联,获得令人满意的线性回归方程,相应的相关系数r依次为0.975 8、0.984 6、0....  相似文献   

16.
合成了双头基多氟烷基两亲杯[4]芳烃化合物1和2,利用表面压一面积(π-A)等温线、压缩/扩张循环等温线与膜稳曲线研究了他们在空气/水相界面的成膜性能,并用紫外光谱和原子力显微镜对组装的LB膜进行了结构表征。结果表明:化合物1和2在空气/水相表面均能很好的形成稳定的Langmuir膜,取代基碳原子数的增加使得化合物2的Langmuir膜单分子面积增加,崩溃压相应减少,组装的LB膜均为H-聚集体,结构均匀,稳定性好。  相似文献   

17.
用混合醛与吡咯缩合,合成了七种对称及不对称的中位硝基取代苯基卟啉及其还原产品:TPP(NO_2)_n,TPP(NH_2)_n[n=0,1,3,4)。研究了它们的吸收光谱,发现苯基上取代基对吸收光谱有较大的影响,而且所用溶剂的极性也会影响光谱的特性;此外,还对这些化合物的荧光光谱进行了测定并讨论。  相似文献   

18.
A few derivatives of calixarenes have been synthesized and characterized by IR, ^1H NNtR, thermal and elemental analysis. The transport of potassium or calcium ion through the liquid membrane, in which the derivatives act as carriers, has been studied. The electron-effect of the substituent on the upper rim of calixarene possesses important effect on the net transport of metal ions. The p- tert-butylcalix[4]arene is the best carrier of calcium ion, compared with p-tert-calix[4]arene(n = 4, 6, 8). The ptert-butylcalix[4]arene acid is better than p-tert-butylcalix [4]arene. The calixr43crown is the best carrier of calcium ions of all the carriers. The pH gradient between the source and receiving phase, and the concentration of K^+ , Ca^2+ ions in the source phase affect mainly transport. After the transport, the pH value of the source phase is found to be decreased, once the calix [n ] arene derivatives act as carrier. But it is not the case for the calix[n] crowns. It might be interpreted as the result of their different mechanisms.  相似文献   

19.
合成了杯[4] 芳烃、四对叔丁基杯[4] 芳烃、四乙氧基羰基甲氧基四对叔丁基杯[4] 芳烃、四乙酰基甲氧基四对叔丁基杯[4] 芳烃等4 种杯芳烃,研究了这些杯芳烃对铁( Ⅲ) 的萃取化学,讨论了这些体系的萃取机理,并求出了它们的萃取平衡常数  相似文献   

20.
设计了用于催化不对称安息香缩合的手性卡宾催化剂(1).以L-丝氨酸为起始原料,经过七步反应合成了其前体(月)-5-二苯甲基-2-苯基-5,6-二氢嗯唑并[2,3-c][1,2,4]-2-三唑盐酸盐(9).  相似文献   

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