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1.
谢政  张炜  黄鹏程 《有机化学》2002,22(8):543-554
芳炔类大环化合物是最近10年来新兴的一种富碳共轭大环状分子,迅速发展到 近100种,可在光、电、磁、纳米等功能材料中得到广泛应用,引起了人们极大的 兴趣,对芳炔类大环化合物的研究,特别是合成方法和性质进行了综述,并提出了 这一领域的发展方向和需要解决的重点课题。  相似文献   

2.
A simple, efficient, and flexible procedure for the synthesis of chiral, amphiphilic, and water-soluble macrocycles is reported. Acylation of p-xylylenediamine with Nα-Fmoc-protected glycine, l-aspartic acid, l-glutamic acid, and l-arginine, followed by removal of Fmoc-groups, gave amino acid:p-xylylene conjugate diamines, which were converted to ten macrocycles via stepwise urea formation using p-nitrophenyl chloroformate. l-Aspartic acid-containing macrocyles proved to be soluble in aqueous buffers and a macrocycle containing four aspartate residues was found to recognize arginine and arginine esters with moderate affinity.  相似文献   

3.
Fully conjugated macrocycles 1a?1c composed of m-diethynylene-phenylene-bridged two dibenzofuran, dibenzothiophene and carbazole units were synthesized via Sonogashira cross coupling reactions under high-diluted condition. These conjugated macrocycles were fully characterized by 1H NMR, 13C NMR, FT-IR, Mass spectroscopies and elemental analysis. Photophysical and redox properties of 1a?1c were investigated by means of UV–vis/fluorescence spectroscopies and cyclic voltammetry, respectively, and those features were compared with those of the corresponding linear phenylethynyldibenzoheterols 11a?11c. Furthermore, their structural and electronic insights were studied by theoretical calculations at the B3LYP/cc-pVDZ//B3LYP/6-31G(d) level of theory.  相似文献   

4.
The use of orthogonally protected cyclam and 1,9-dithia-5,13-diazacyclohexadecane macrocycles, in combination with aza-18-crown-6, has enabled the efficient synthesis of a new heterotritopic macrocyclic ligand incorporating N4-, N2S2- and NO5-donor sites. A similar strategy has allowed the incorporation of cyclam and 1,9-dithia-5,13-diazacyclohexadecane into a cofacial ligand. Further, the synthesis of novel tetramacrocyclic ligands has been achieved in which the macrocycles are linked in a cyclic arrangement. The availability of different binding sites in the respective products makes the latter suitable candidates for the synthesis of a range of mixed-metal multinuclear complexes.  相似文献   

5.
Ashraf A Abbas 《Tetrahedron》2004,60(7):1541-1548
The 13-hydroxy macrocycles 7a-d were prepared in 40-50% yields by the condensation of 1,ω-bis(4-amino-1,2,4-triazol-3-ylsulfany)alkanes 2a-d with 1,3-bis(2-formyphenoxy)-2-propanol (9). Acylation of 7a-d with 2-chloroacetylchloride gave the corresponding esters 11a,b. Amination of 11a,b with different amines in acetone furnished exclusively the target lariat macrocycles 12a,b and 13 in 60-70% yields. Reaction of 2 equiv. of the macrocycles 11a,b with 1 equiv. of piperazine afforded the novel bis macrocyles 14a,b in 50-60% yields. Reduction of 7a-d with NaBH4 afforded the corresponding 13-hydroxyazathia crown ethers 15a-d in 65-70% yields.  相似文献   

6.
Amphiphilic macrocycles consisting of cholates and l-tryptophan were prepared by the copper-catalysed alkyne–azide cycloaddition. The macrocycles helped glucose permeate lipid bilayer membranes. The macrocycle with two cholates was significantly more active in the glucose transport than the one with three cholates. Inclusion of 30–50% cholesterol in the bilayer accelerated the glucose transport monotonously. The unusual cholesterol effect was explained by the hydrophobically driven pore formation, in which the associative interactions of the water molecules inside the macrocycles prompted the macrocycles to stack over one another to avoid unfavourable water–lipid hydrocarbon contact. Fluorescence quenching by water- and oil-soluble quenchers provided additional evidence for the better penetration of the dicholate macrocycle into the bilayers, consistent with the stacking model. Rigidity in the macrocycle structure was hypothesised to be the main reason for the higher transport activity and deeper membrane-penetration of the dicholate macrocycle compared with those of the tricholate.  相似文献   

7.
Optically active macrocycles (R, R)-8-10 and diastereomeric mixtures of (±)-8-10 and meso-(R, S)-8-10 were prepared containing two (R)- or (S)-α-phenylglycine units as sources of chirality.  相似文献   

8.
The influence of the nature of a solvating medium on the chromophore properties and stability of alkyl-substituted biladiene-a,c dihydrobromide, a synthetic analogue of a bile pigment bilirubin, was analyzed. The results of the spectrophotometric study of the protonation of a tetrapyrrol ligand and of the complex formation with Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) acetates in DMF at 298.15 K were considered. Depending on the nature of a complex-forming cation and concentrations of reagents in solution the formation of complexes of three various types is possible: porphyrin-like (1:1), binuclear with different ligands (2:1), and binuclear biligand (2:2). The nature of metal cation renders essential influence on the formation of coordination polyhedra of the metal chelates with various structure.  相似文献   

9.
A novel convergent approach to dendritic macromolecules is described in which 4,6-dichloro-2-(4-methoxyphenyl)-pyrimidine is used as the building block. The nucleophilic aromatic substitution reaction at this AB2-monomer was used as the key step in the propagation of the dendrons. Different core reagents were used to form the dendrimers, including a 5,15-bis(pyrimidyl)porphyrin core. Fourth-generation dendrons and third-generation dendrimers could be synthesized. The presented dendrimers are promising candidates to be used in applications where a more rigid structure and a larger resistance towards the applied conditions is required.  相似文献   

10.
Two macrocyclic bis-thiourea hosts 5 and 6 were constructed and their interactions with two dicarboxylates of similar size (pimelate = flexible and terephthalate = rigid) were evaluated using 1H NMR titration techniques. In contrast to previous work with thiourea functionalised [n]polynorbornanes (where a notable increase in H:G affinity was noted for the rigid guest), the new macrocyclic hosts, in particular host 6, bind pimelate more strongly than terephthalate (for 6 binding pimelate log Ka = 4.7, terephthalate log Ka = 3.7). A binding arrangement in which the flexible dicarboxylate is ‘perched’ above the macrocycle is proposed to justify these results.  相似文献   

11.
A series of macrocyclic arylene ether ketone oligomers from 4,4′-difluorobenzophenone, 2,4′-difluorobenzophenone and 1,3-bis(4′-fluorobenzoyl)benzene were prepared via aromatic nucleophilic substitution according to the pseudo-high dilution principle. Small-size aromatic macrocycles were isolated by silica gel column chromatography with cyclohexane/ethyl acetate as eluent. The chemical structures of these small-size macrocycles were characterized by matrix-assisted laser desorption ionization–time-of-flight–mass spectrometry (MALDI–TOF–MS), IR, 19F-,1H-, and 13C-NMR, and GPC techniques. Molecular chain length and steric hindrance of monomers affected the product compositions. The NMR results show that there are different chemical shifts in the different ring-size macrocyclic poly arylene ether ketones in spite of having the same repeating unit. The crystallizability and thermal properties of small-size arylene ether ketone macrocycles were also investigated by DSC, WAXD, TGA, and the results suggest that the crystallization and thermal properties are related to their intrinsic chemical structures. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1957–1967, 1999  相似文献   

12.
13,14-bis(Hydroxyimino)-4,7-bis(ferrocenylmethyl)-2,3,4,5,6,7,8,9-octahydrobenzo[k]-4, 7-diaza-1,10-dithiacyclododecine[13,14-g]-quinoxaline (H2L) has been prepared from (E,E)-dichloroglyoxime and 12,13-diamino-4,7-bis(ferrocenylmethyl)-2,3,4,5,6,7,8,9-octahydrobenzo[k]-4,7-diaza-1,10-dithiacyclododecine which was synthesized from 12,13-dinitro-4,7-bis(ferrocenylmethyl)-2,3,4,5,6,7,8,9-octahydrobenzo[k]4,7-diaza-1,10-dithia cyclododecine. Mononuclear nickel(II) and copper(II) complexes of H2L have a metal-ligand ratio of 1?:?2 and the ligand coordinates through two nitrogen atoms, as do most (E,E)-dioximes. The homotrinuclear [Cu(L)2Cu2(dipy)2](NO3)2 compound coordinates to the other two copper(II) ions through deprotonated oximate oxygens and two 2,2′-dipyridyl as an end-cap ligand to yield the trinuclear structure. The ligand and its complexes have been characterized on the basis of 1H, 13C NMR, IR and MS spectroscopy and elemental analyses.  相似文献   

13.
何永炳  LEHN  Jean-Marie 《中国化学》2000,18(3):384-387
The 6-hydroxymethyl-6'-tetrahydropyranyloxymethyl-2, 2'-bipyridine (2) was synthesized by the reaction of 6,6'-dihy-droxymethyl-2, 2'-bipyridine (1) with 3, 4-dihydropyran (DHP). 6-Tetrahydropyranyloxymethyl-6'-iodomethyl-2, 2'-bipyridine (5) was obtained from mesylate and iodizating reaction of compound 2. The coupling of 2 and 5 followed by hydrolysis gave bis(6'-hydroxymethyl-2,2'-bipyridme-6-methyl)ether (7) .The macrocydic ligand 8 was obtained by treating 7 and 6,6'-dibromomethyl-2,2'-bipyridine. The synthetic conditions of the intermediate 2 and macocyclic ligand 8 were discussed.  相似文献   

14.
The synthesis, characterization and singlet oxygen quantum yield of novel unsymmetrical dendrons containing photosensitizing units at their periphery is reported. Boc-protected 2,2′-(ethylenedioxy)-bis-ethylamine reacted with methyl acrylate and ethylene diamine to give half-dendrimers 4 and 5 with 2 and 4 end groups, respectively. Amine-tethered porphyrins and compounds 4 and 5 were efficiently coupled in DMF at 100 °C to give the functionalized dendrons. UV-visible and fluorescence emission spectra showed that the photophysical properties of the porphyrins were retained in the dendrimers.  相似文献   

15.
Phosphoryl azides are known as azide-transfer agents in organic chemistry; such behavior denotes the pseudo-halogen character of the azide group when linked to a tetracoordinated phosphorus atom, but it was considered up to now only for the functionalization of organic substrates by N3. We show in this paper that the azide can also be considered as a good leaving group, which facilitates the functionalization of the phosphorus atom which bore it. This reaction is first demonstrated on a small thiophosphoryl azide, then applied to the functionalization of more complex macromolecules, i.e. macrocycles incorporating in their structure thiophosphoryl azido groups.  相似文献   

16.
A novel three-component copolymer (PFDP), derived from 9,9-dihexylfluorene, diketopyrrolopyrrole( DPP), and 10-octylphenothiazine, was synthesized through palladium-catalyzed Suzuki polycondensation in good yields. PFDP possessed moderate molecular weight and polydispersity, well-defined structure, and excellent thermal properties with an onset decomposition temperature at 357°C. PFDP in thin film exhibited red photoluminescence from DPP chromophore exclusively, with a peak at 602 nm. Electron-rich phenothiazine units sighificantly improved the injection and transport of holes by incorporating into polymer backbone. Light-emitting device was fabricated in the ITO/PEDOT: PSS/PVK/ polymer/Ba/Al configuration using PFDP as the emitting layer. The device based on PFDP showed red emission [CIE coordinate value (0.62, 0.38)] that was close to the standard red (0.66, 0.34). The results on electroluminescent performance revealed that PFDP may be a promising candidate for the red emitter with a maximum brightness of 259 cd/m2 and a maximum external quantum efficiency of 0.25%.  相似文献   

17.
A novel fluorenylidene containing a ferrocene unit has been electropolymerized. In this polymer, the ferrocene unit is grafted to the main polyfluorenylidene chain as a pendant group. The polymer is electroactive in non-aqueous and aqueous media.  相似文献   

18.
The novel tetrasubstituted metal-free phthalocyanine (6) and metallophthalocyanines (7, 8) bearing four 14-membered tetraaza macrocycles moieties on peripheral positions have been synthesized by cyclotetramerization reaction of phthalonitrile derivative (5) in a multi-step reaction sequence. The new compounds were characterized by a combination of IR, 1H NMR, 13C NMR, UV-vis, elemental analysis and MS spectral data.  相似文献   

19.
A novel type of double butterfly, two mu-CO-containing dianions {[(mu-CO)Fe2(CO)6]2[mu-SCH2(CH2OCH2)nCH2S-mu]}2- (m1, n = 2, 3), has been synthesized from dithiol HSCH2(CH2OCH2)nCH2SH (n = 2, 3), Fe3(CO)12, and Et3N in THF at room temperature. While dianions m1 react in situ with CS2 followed by treatment with dihalide 1,4-(BrCH2)2C6H4 or 1,4-I(CH2)4I to give macrocyclic clusters [mu-SCH2(CH2OCH2)nCH2S-mu](mu-CS2ZCS2-mu)[Fe2(CO)6]2 (1a, n = 2, Z = 1,4-(CH2)2C6H4; 1b, n = 3, Z = (CH2)4), reactions of dianions m1 with (mu-S2)Fe2(CO)6 followed by treatment with dihalide 1,4-I(CH2)4I afford macrocyclic clusters [mu-SCH2(CH2OCH2)nCH2S-mu]{[Fe2(CO)6]2(mu4-S)}2[mu-S(CH2)4S-mu] (2a, n = 2; 2b, n = 3). The crystal structures of 1a and 2b are described.  相似文献   

20.
Abstract

Novel bis[2-(thiazol-2-yl)acetonitriles], linked to aliphatic cores via ethers, were prepared by the reaction of the appropriate bis(2-bromoethan-1-one) with 2-cyanothioacetamide in dioxane at reflux. Bis[2-(thiazol-2-yl)acetonitriles] were taken as key intermediates for the preparation of a new class of macrocyclic dicarbonitriles bearing two thiazole units and containing two O2-donor sets and fused with two benzene units. The target macrocyclic dicarbonitriles were prepared by the cyclocondensation of bis[2-(thiazol-2-yl)acetonitriles] with the appropriate bis(aldehydes) in N,N-dimethylformamide in the presence of piperidine at reflux. Moreover, a new class of pyrazolo-fused macrocycles containing thiazole subunits were prepared by the reaction of macrocyclic dicarbonitriles with hydrazine hydrate in ethanol at reflux. The structures of the novel macrocycles bearing thiazole subunits were elucidated by considering their elemental analyses as well as their IR, mass, 1H NMR and 13C NMR spectral data.  相似文献   

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