氮杂冠醚的研究：Ⅳ.大环仲胺型氮杂冠醚的合成

在高度稀释条件下芳香族二胺与相应的二酰氯起环化缩合反应,合成了5种大环酰胺型氮杂冠醚,接着用 LiAlH_4-THF 还原生成大环仲胺型氮杂冠醚;这两类冠醚的结构均经元素分析、IR、~1HNMR 和 MS 所证实。     

新型大环聚醚的合成及配位性能

本文报道一类新型大环聚醚的合成.在以1,7-二氧杂-4,10-二氮杂环十二烷(1a)及1,7,10,16-四氧杂-4,13-二氮杂环十八烷(1b)中的两个仲胺上进行含醚键的卤代烷取代反应,获得一批带有两个含有侧链醚键的新型冠醚.以碳酸钾为缩合剂,所得冠醚碱金属配合物经酸分解及四甲基氢氧化铵处理后,得游离的大环聚醚. 用溶解度法初步测定了这类冠醚对碱金属的配位性能.结果指出,其母环及侧链上氧原子数的多少及碱金属离子半径的大小均影响配合物的稳定性,其中有些冠醚对碱金属有良好的配位能力,有的还具有优异的选择性,例如N,N′-β-甲氧基乙基-1,7-二氧杂-4,10-二氮杂环十二烷(13a)对钾及钠离子的选择比大于18-c-β,并比4,4′(5′)-二甲基苯并-30-c-10还高.     

140Cu/MCM-41和14T2Cu/MCM-41的制备与表征

二氧四胺大环和取代二氧四胺大环化合物兼有大环氮杂冠醚和低聚肽的性质,能和很多过渡金属离子(Cu²⁺,Ni²⁺,Mn²⁺,Co²⁺等)形成具有特殊功能的配合物.如十四元二氧四胺大环Co(Ⅱ)配合物在-70℃加入过量的咪唑或吡唑后.     

相转移催化反应研究I.相转移催化剂在二卤卡宾与对-甲基苯乙烯加成反应中结构效应

本文研究了不同结构的季铵盐,季磷盐,常用冠醚以及N,N'-二取代氢杂冠醚等相转移催化剂,催化产生的二溴卡宾与对-甲基苯乙烯的加成反应。结果证明,具有对称烷基结构的季铵盐的催化性能优于碳链较长,对称性较差的季胺盐。在冠醚类相转移催化剂中,新型N,N;-二取代氮杂冠醚优于常用冠醚及穴醚[2.2.2]。在十九种相转移催化剂中,以N,N'-双(3',6'-二氧杂葵烷基)-1,7,10,16-四氧杂-4,13-二氮环杂十八烷[简称二丁基2.2(2.2)]的催化性能最佳。简要讨论了盐及大环多醚的PTC反应机理及催化性能,还比较了氘代氯仿、氘代氢氧化钠重水体系进行的相转移催化反应。     

大环多胺及其金属配合物与DNA的相互作用

本文综述了近年来基于大环多胺及其金属配合物与DNA相互作用的研究进展,着重介绍本课题组在有关单双核、多核以及功能化大环多胺衍生物及其金属配合物与DNA相互作用方面的研究和发现,并对其在化学核酸酶方面的应用进行了讨论。在单双核大环多胺衍生物方面,我们分别合成了以吡啶、苯环、咪唑、三氮唑为侧臂的单核大环多胺金属配合物,同时合成了以刚性桥相连的双核配合物和以柔性链相连的双核配合物。并研究这些单双核大环多胺与DNA的相互作用,发现以刚性链相连的双核大环多胺金属配合物具有很好的切割DNA的性质,可以在低浓度、短时间内切断DNA。在功能化大环多胺方面,我们合成了含有碱基、PNA单体、咪唑鎓盐、冠醚、二茂铁等功能化基团的大环多胺衍生物及金属配合物,并研究了其与DNA的相互作用。在多核大环多胺方面,我们合成了基于大环多胺的寡聚物,研究发现该类物质可与DNA形成复合物,从而有效地保护DNA免于酶解。     

由(+)-2-氨基丁醇合成氮杂手性冠醚

手性冠醚由于具有手性识别和不对称催化有机反应的性质而受到人们的重视,有关它们的合成及性质,已很多论述。氮杂冠醚则是合成穴醚、双冠醚、套索冠醚(LariatEther)等的重要中间体,也可与高分子材料(高分子载体或高分子基质)连接,用于有机化合物的色谱分离。氮杂手性冠醚兼备手性和氮杂冠醚两种特性,而可能具有广泛的用途。     

大环配合物在核酸切割中的应用

核酸切割试剂的研究是化学和分子生物学中最为活跃的前沿领域之一.研究核酸切割试剂,不仅是因为对核酸酶催化机理进行深入了解之需,同时还因为人工核酸酶在基因治疗中有着诱人的前景.大环配合物的合成、结构及其对核酸的切割作用已有广泛的文献报道.本文综述了作为重要的核酸切割试剂的大环多胺配合物和氮杂冠醚配合物对核酸的切割作用及其规律性,并展望了今后的发展与应用方向.     

含二氮杂-18-冠-6-单元的向列型液晶化合物的合成和性质

本文报道三种含芳酯的二氮杂-18-冠-6的合成.它们显示出向列型液晶的特性.探讨了分子结构对液晶性质的影响.冠醚液晶7在无机盐掺杂后是否仍有液晶性质与掺杂的无机盐阴离子的结构有关,而与阳离子的种类无关.无机盐掺杂量对液晶清亮点的影响也作了研究.     

含氮杂冠醚结构单元的吲哚啉螺苯并吡喃的合成和性质

含氮杂冠醚结构单元的吲哚啉螺苯并吡喃的合成和性质伍新燕吴成泰＊（武汉大学化学系武汉４３００７２）关键词氮杂冠醚，螺吡喃，合成，性质１９９７－０６－０５收稿，１９９７－１２－０８修回国家自然科学基金和国家教委博士点专项基金资助项目含冠醚结构单元的吲哚啉...     

含二氮杂-18-冠-6-单元的向列型液晶化合物的合成和性质

本文报道三种含芳酯的二氮杂-18-冠-6的合成。它们显示出向列型液晶的特性。探讨了分子结构对液晶性质的影响。冠醚液晶7在无机盐掺杂后是否仍有液晶性质与掺杂的无机盐阴离子的结构有关, 而与阳离子的种类无关。无机盐掺杂量对液晶清亮的影响也作了研究。     

Synthesis of New Crown Ethers Containing Appended Pyridine, 10-hydroxybenzoquinoline, 8-hydroxyquinoline and 2-amino-1-hydroxybiphenyl Sidearms

Twelve crown ethers containing one or two arms were synthesized. Two methods were used to attach arms to the azacrown ethers. Ligands 4 - 12 were prepared by a nucleophilic substitution of secondary macrocyclic amine functions on RX ( X=bromide or tosylate groups). Ligands 13 - 15 were obtained via a Mannich reaction of secondary macrocyclic amines with 5-chloro-8-hydroxyquinoline or a substituted-phenol. Diaza-18-crown-6 was treated with 2-bromomethyl-9-methyl-1,10-phenanthroline at the same conditions in which 4 - 8 and 10 - 12 were prepared. In this case, the main product was the diazacrown ether containing one arm. Twelve new aza-crown ethers bearing aromatic and aliphatic side arms were prepared by nucleophilic substitution by secondary macrocyclic amine functions on halide or tosylates or via a Mannich reaction of the macrocyclic secondary amines with phenolic compounds. R=derivatives of pyridine, 8-hydroxyquiniline, and 1-hydroxybiphenyl. Crown ether include aza-15-crown-5 diaza-18-crown-6 diazatrithia-15 (and 16)-crown-6 and diaza-21-crown-7     

几种三相催化剂在氰代、碘代和二氯卡宾反应中的催化行为

本工作研究了带含氧冠醚、氮杂冠醚、酚醛型冠醚、开链冠醚的四种聚合物作为三相催化剂在氰代、碘代和二氯卡宾反应中的催化活性,其中以冠醚环上带有叔胺氮原子的氮杂冠醚聚合物催化活性最好。     

Synthesis and metal ion complexation studies of proton-ionizable calix

A series of novel N-chromogenic calix[4]arene azacrown ethers were synthesized as selective extractants of potassium ion. 1,3-Alternate calix[4]arene azacrown ethers were prepared by reacting 25,27-dipropyloxy-26,28-bis(5-chloro-3-oxapentyloxy) calix[4]arenes with p-toluenesulfonamide in the presence of potassium carbonate. The coupling reaction of calix[4]arene azacrown ether with 2-hydroxy-5-nitrobenzyl bromide in the presence of triethylamine in THF gave the chromogenic calix[4]arene azacrown ether in moderate yield. These compounds show high potassium selectivity over other metal ions as shown by two-phase extraction, bulk liquid membrane, and 1H NMR studies on a ligand-metal complex. It is assumed that the OH of the chromogenic group attached on nitrogen can assist the complexation by encapsulation of the metal.     

Recoordination of a metal ion in the cavity of a crown compound: a theoretical study. 1. Conformers of arylazacrown ethers and their complexes with Ca2+ cation

Photoinduced recoordination of Ca²⁺ complexes of the photochromic azacrown ethers is studied by the density functional method. The study included model arylazacrown ethers containing various acceptor groups in the aromatic ring in the para position to the azacrown ether moiety and a real azacrown-containing styryl dye. It is found that both free azacrown ethers and their complexes can adopt two types of conformations: (1) axial conformations, in which the aromatic ring axis passing through the crown ether nitrogen N_cr and the opposite atom of the aromatic ring is perpendicular to the root-mean-square (RMS) plane of the crown ether (least-squares fitted plane for all the crown ether atoms), and (2) equatorial conformations, in which the aromatic ring axis only slightly deflects from the RMS plane of the crown ether. In the equatorial conformers, the metal cation is coordinated only to the O atoms of the azacrown ether cycle, the metal—nitrogen bond is broken, and N_cr is conjugated with the aromatic ring. In the axial conformers, the metal cation is additionally coordinated to N_cr. It is found that the presence of an acceptor group bearing a formal positive charge decreases the relative energy of the equatorial conformer and favors metal—nitrogen bond dissociation, which results in the recoordination of the metal cation. However, a long distance between the charged group and N_cr has the reverse effect. The photoinduced recoordination observed in the alkaline-earth metal complexes of the photochromic azacrown ethers is explained by the transitions between the axial and equatorial conformers facilitated by the charge transfer in the excited state of the complex.     

Host-guest complexation of endohedral metallofullerene with azacrown ether and its application

Complexation of endohedral metallofullerene La@C(82)-A (1) with macrocyclic compounds, such as 1,4,7,10,13,16-hexaazacyclooctadecane (2), 1,4,7,10,13,16-hexamethyl-1,4,7,10,13,16-hexaazacyclooctadecane (3), mono-aza-18-crown-6 ether (4), 18-crown-6 ether (5), and p-tert-butylcalix[n]arenes (n = 4-8, 6-10), for the first time is examined. Among them, 1 forms a complex with azacrown ethers 2-4 while accompanying the electron transfer between them. This is characteristic of endohedral metallofullerene and caused by its low reduction potential. Activation energies, DeltaG(et), for the electron transfer from 2-4 to 1 are 4.6, 2.8, and 11 kcal/mol, respectively. These small DeltaG(et) values indicate that the electron transfer from the azacrown ethers to 1 is facile in the ground state. Furthermore, the selective isolation of lanthanum endohedral metallofullerenes from the extracts of soot is accomplished by utilizing the complexation of 1 with 2.     

DNMR study of the azacrown ether conformations in solution

The NMR methods (including ¹H NMR, ¹³C NMR, variable temperature method and the novel ID EXSY technique) were employed to study the conformation of azacrown ethers 1—5 in solution. There are two classes of conformation in which the azacrown ethers exist in solution according to their molecular structure. Two kinds of intramolecular motion of the azacrown ethers were observed, one is the vibration of the macrocyclic ring and the other is its inversion. The ether rings which contain oxygens are more flexible than that constructed by nitrogens in the present case because of the tetrahedron structure of the nitrogen atoms and the hindrance of the groups Ts connected to the nitrogens. Some thermodynamical parameters of the ring inversion process were obtained.     

氮杂冠醚研究Ⅺ．叔胺型氮杂冠醚的合成

１１种酰胺型氮杂冠醚用ＬｉＡｌＨ４－ＴＨＦ体系还原，高收率地合成了新的叔胺型氮杂冠醚；通过２，３－苯并－１０－氮杂－１，４，７，１３－四氧杂环十五－２－烯与丙烯腈进行氰乙基化反应，同样制得了一种新的叔胺型氮杂冠醚。１２种新化合物的结构均经元素分析、ＩＲ、１ＨＮＭＲ和ＭＳ所证实。讨论了这类氮杂冠醚的质谱裂解过程     

Preparation of N-aryl azacrown ether derivatives,using arene-iron chemistry

m- or p-phenylenediamine and m- or p-chlorophenyl-substituted azacrown ether derivatives were synthesized through sequential nucleophilic substitution of [(eta(5)-cyclopentadienyl)(eta(6)-(m- or p-dichlorobenzene))]iron hexafluorophosphate by azacrown ethers and cyclohexaamines. Monoarylation is the main reaction for diazacrown ethers. The overall yield from the starting complex is 50-96% for multiple steps.     

Synthesis of new lariat ethers containing polycyclic phenols and heterocyclic aromatic compound on graphite surface via mannich reaction

Synthesis of novel lariat ethers containing polycyclic phenols and heterocyclic aromatic compound using graphite via Mannich reaction are herein described. For this purpose N-(methoxymethyl) azacrown ether 4 was synthesized in nearly quantitative yield. The reaction of N-(methoxymethyl) azacrown ether 4 with polycyclic phenols and heterocyclic aromatic compound was performed in 10-20 min in the presence of graphite. The graphite powder can be reused up to five times after simple washing with acetone.