具有不同柱状结构的苯并菲盘状液晶化合物的合成及自组装

合成了3种含有不同长度烷基链的苯并菲盘状液晶化合物; 通过1H NMR 和 MALDI-TOF MS对其结构进行了表征; 利用差示扫描量热法(DSC)、热台偏光显微镜(POM)和小角X射线散射实验(SAXS)对3种液晶化合物的自组装行为进行了研究. 结果表明, 烷基链的长度对苯并菲盘状液晶化合物自组装结构的影响显著. 柔性链为辛基的苯并菲盘状液晶化合物自组装成六方柱状液晶相; 柔性链为十二烷基的化合物自组装成倾斜柱状液晶相; 而柔性链为十六烷基的化合物则未形成液晶相.     

Three-dimensional self-organization of supramolecular self-assembled porphyrin hollow hexagonal nanoprisms

A self-assembly technique assisted with surfactant is developed to fabricate one-dimensional (1D) nanostructure of zinc meso-tetra (4-pyridyl) porphyrin. The so-prepared nanostructure appears in a shape of hollow hexagonal nanoprism with uniform size. The length and aspect ratio of the nanoprisms is easily tunable by controlling the stoichiometric ratio of porphyrin over surfactant. The internal structure of the nanoprisms is well described by XRD. Furthermore, as a result of dispersivity and regular geometric shape, these nanoprisms can readily self-organize into an ordered, smectic three-dimensional (3D) architecture through simple evaporation of the solvent. The results should be significant in porphyrin crystallization and porphyrin application in optoelectronic device, catalysis, drug delivery, and molecular filtration.     

Discotic liquid crystals: a new generation of organic semiconductors

Discotic (disc-like) molecules typically comprising a rigid aromatic core and flexible peripheral chains have been attracting growing interest because of their fundamental importance as model systems for the study of charge and energy transport and due to the possibilities of their application in organic electronic devices. This critical review covers various aspects of recent research on discotic liquid crystals, in particular, molecular design concepts, supramolecular structure, processing into ordered thin films and fabrication of electronic devices. The chemical structure of the conjugated core of discotic molecules governs, to a large extent, their intramolecular electronic properties. Variation of the peripheral flexible chains and of the aromatic core is decisive for the tuning of self-assembly in solution and in bulk. Supramolecular organization of discotic molecules can be effectively controlled by the choice of the processing methods. In particular, approaches to obtain suitable macroscopic orientations of columnar superstructures on surfaces, that is, planar uniaxial or homeotropic alignment, are discussed together with appropriate processing techniques. Finally, an overview of charge transport in discotic materials and their application in optoelectronic devices is given.     

Liquid crystalline order from ortho-phenylene ethynylene macrocycles

Triangular ortho-phenylene ethynylene (o-PE) cyclic trimers represent a novel member of shape-persistent macrocycles. Shape-persistent cyclic structures remain of great interest as molecular components in the fields of supramolecular materials, host-guest chemistry, and materials science. Novel discotic liquid crystalline properties are reported from triangular-shaped o-PE macrocycles containing branched alkoxy- and/or triethylene glycol (TEG) side chains using polarized optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The macrocycles self-assemble into thermotropic rectangular columnar (Colr) (for M1), hexagonal columnar (Colh) (for M2), and discotic nematic (for M3) mesophases at room temperature. This work shows clearly that electron-rich PE macrocycles can form LC materials. Alkyl side chains in M1 promote order, while hydrophilic side chains of M2 generate an amphiphilic structure that provides a different driving force for organization. The ability to create ordered self-assembling materials from these novel electron-rich macrocycles is important in nanotechnology.     

卟啉类化合物分子光电器件研究进展

分子电子器件是未来分子电路的微电子元件,已成为有机功能纳米材料研究的热点。 卟啉类化合物的π共轭体系表现出的独特光电性能和良好的热稳定性,使其作为光电器件、模拟生物酶、分子识别和传感材料在材料化学、医学、生物化学和分析化学等领域展现出良好的应用前景,由于卟啉分子平面结构的易修饰性,常用卟啉化合物组装单元来构建功能化的卟啉光电器件。 本文综述了卟啉类化合物的特点及其在光电器件中的应用进展。     

Dynamic combinatorial olefin metathesis: templated synthesis of porphyrin boxes

A porphyrin macrocyclic square is efficiently prepared by a dynamic combinatorial approach to olefin metathesis and shown by scanning tunneling microscopy (STM) to self-assemble into highly ordered arrays on a graphite surface.     

Nonlinear Optical Properties of Porphyrin Derivatives with Electron‐donating or Electron‐withdrawing Substituents

To investigate photoelectric properties of meso‐extended porphyrin derivatives with electron‐donating or electron‐withdrawing substituents, a series of functionalized porphyrin materials have been designed and synthesized by Suzuki coupling reaction. The meso‐extended structures were fully characterized by ¹H NMR, IR spectroscopy and mass spectrometry. The photophysical properties of porphyrin derivatives were carefully examined by UV‐Visible and fluorescence spectra, and the solvatochromic effect was observed and discussed. In particular, Z‐scan technique was employed to characterize the third‐order nonlinear optical (NLO) properties of the products such as nonlinear absorption and refraction, the third‐order nonlinear refractive indexes (??⁽³⁾‐value) of these porphyrin derivatives achieved 3.9×10^?12 esu. In addition, the compounds could be self‐assembled into highly organized morphologies through phase‐exchange method. All the results indicated that the discotic materials have the potential for optoelectronic applications.     

卟啉纳米组装与生物传感

卟啉是一类重要的有机共轭分子,可以模拟许多酶的活性中心。一系列卟啉仿生酶已被合成,并用于模拟生物蛋白酶的催化活性,包括平面卟啉、栅栏卟啉、扩展环卟啉和三元环卟啉。在生物体内,许多金属蛋白酶经常自组装成纳米尺度的超分子结构来实现其基本的生物催化作用。卟啉可以通过共价或者非共价作用有序组装在纳米材料上,实现其模拟金属蛋白酶的功能。金属卟啉是良好的电子媒介体,对生命过程相关小分子的氧化还原具有较好的电催化活性。因此,金属卟啉纳米组装形成的纳米材料复合物可用于新型电化学生物传感器的构建。基于卟啉纳米材料复合物的光物理和光化学性质构建的新型光电化学生物传感平台已用于生物分子的检测。本文主要从卟啉仿生酶的合成、有序纳米组装和卟啉纳米复合物的生物传感进行评述,为构建新型电化学和光电化学传感器提供有用信息。     

Multiscale fibers via supramolecular self-assembly of a fully rigid,discotic aromatic aramid molecule

We synthesized a fully rigid, water soluble discotic-shaped aromatic aramid molecule, which can spontaneously self-assemble into multiscale fibers (from nano- to micro-scale in both length and diameter), depending on the molecular states (e.g., solution, liquid crystals and solid state). In diluted solution (below 0.086 g/mL), the discotic molecule tend to self-assemble into nanofibers. As the concentration increased (0.086–0.28 g/mL), it exhibits supramolecular liquid crystalline phase with microfiber texture. While, solid power under circumstance with 83% relative humidity favors the formation of rod-like shaped polymorphic crystals in macroscopic size. The unique ‘self-fiber-forming’ property of discotic molecules in different states makes them become an easy processing aramid fiber material, and also allow us to easily prepare microfilm with parallel-aligned nanofibers, which could be a promising candidate for ion conductivity material such as polymer proton exchange membrane (PEM) for fuel cell.     

Eutectic mixtures with plastic columnar discotics: molecular structure,phase morphology and kinetics of phase separation

We report the properties of eutectic mixtures of triphenylenes displaying a highly ordered columnar phase with a low molar mass non‐discotic compound. Such highly ordered triphenylenes display large charge carrier mobilities which are strongly controlled by the state of order in the discotic phase. The motivation was to establish how the state of order—molecular order, phase morphology, temperature ranges of phase stabilities and macroscopic orientational order—can be influenced by mixing. The studies reveal that the molecular order, in particular the mutual arrangement of the columns and the intracolumnar order, are unaffected by dilution of the discotic compound, whereas the phase morphology and the kinetics of phase separation change significantly with dilution. Rod‐shaped discotic domains with a hexagonal cross‐sectional area are formed via a nucleation process and the rods grow linearly as a function of time. Both the pure discotic phase as well as the discotic domains forming during phase separation can be macroscopically ordered by orientation layers.     

Not Only Columns: High Hole Mobility in a Discotic Nematic Mesophase Formed by Metal‐Containing Porphyrin‐Core Dendrimers

We report a new family of multifunctional liquid‐crystalline porphyrin‐core dendrimers that have coumarin functional groups around the porphyrin core. Porphyrin metalation strongly affects the photophysical properties, and therefore Zn^II and Cu^II derivatives have also been prepared. All the synthesized dendrimers form a nematic discotic mesophase. Their high tendency for homeotropic alignment makes these dendrimers excellent candidates for device applications, owing to their easy processability, spontaneous alignment between electrodes, and self‐healing of defects because of their dynamic nature. The charge mobility values of these materials are the highest ever reported for a nematic discotic phase. Moreover, these values are similar to the highest values reported for ordered columnar mesophases, and this shows that a supramolecular organization in columns is not necessary to achieve high charge mobility.     

Highly ordered arrangement of meso-tetrakis（4-aminophenyl）porphyrin in self-assembled nanoaggregates via hydrogen bonding

meso-Tetrakis(4-aminophenyl)porphyrin(TAPP) can self-assemble into nanostructures with different morphologies by a phase-transfer method.The morphologies(nanospheres,nanorods and nanothorns)of porphyrin nanoaggregates could be easily tuned just by changing the concentration of porphyrin in a proper solvent at room temperature.HRTEM images revealed the formation of highly ordered supramolecular arrays of TAPP,i.e. superlattice of TAPP molecules in nanoaggregates,which agreed well with the size of one molecule of TAPP.UV–vis absorption spectra showed an obvious red shift of the Soret band of TAPP,indicating the formation of J-aggregates of TAPP in nanoaggregates.     

5 nm Ordered Structures Self-Assembled by C2-Symmetric Hybrids with Polyhedral Oligomeric Silsesquioxane and Hexa-peri-Hexabenzocoronene.

Hybrids consisting of polyhedral oligomeric silsesquioxane (POSS) and hexa-peri-hexabenzocoronene (HBC) with a dumbbell topology and C₂ symmetry were designed and synthesized. They self-assemble into 5 nm ordered structures. In particular, the increased steric effect with increasing POSS units stabilizes a square columnar phase (Col_squ) which is important in nanotemplating. These hybrids containing discotic liquid crystal HBC and POSS units have an excellent etching contrast and present an approach to obtain 5 nm nanopatterns.     

Novel Mixed LB Films of Porphyrin and Phthalocyanine Based on Molecular Recognition

Phthalocyaninesaresyntheticsubstancesrelatedtothenaturallyoccurringporphyrins.Itsthermalandchemicalstabilitymakesitveryusefulinmolecularelectronicsl.TheLBfilmsofphthalocyaninehavebeenwidelystudiedinthepastdecade.ButfewreportsonthemixedLBfilmsofphthalocyanineandporphyrinhavebeenpublished"'HerewereportanovelmixedLBfilmfabricatedbydepositingporphyrinandphthalocyaineinonelayerbasedonmolecularrecognition.Figure1.ThestructureofcompoundAandBAsymmetricallysubstitutedphthalocyanineAandporphyrinBa…     

Eutectic mixtures with plastic columnar discotics: molecular structure, phase morphology and kinetics of phase separation

We report the properties of eutectic mixtures of triphenylenes displaying a highly ordered columnar phase with a low molar mass non-discotic compound. Such highly ordered triphenylenes display large charge carrier mobilities which are strongly controlled by the state of order in the discotic phase. The motivation was to establish how the state of order—molecular order, phase morphology, temperature ranges of phase stabilities and macroscopic orientational order—can be influenced by mixing. The studies reveal that the molecular order, in particular the mutual arrangement of the columns and the intracolumnar order, are unaffected by dilution of the discotic compound, whereas the phase morphology and the kinetics of phase separation change significantly with dilution. Rod-shaped discotic domains with a hexagonal cross-sectional area are formed via a nucleation process and the rods grow linearly as a function of time. Both the pure discotic phase as well as the discotic domains forming during phase separation can be macroscopically ordered by orientation layers.     

Effect of terminal substituents on self‐assembly behavior of porphyrin molecules on Ag(110)

Effect of terminal substituents on self‐assembly behavior of porphyrin molecules has been studied with three derivatives modified with distinctly different substituents, 5,15‐(di‐3,5‐di‐tert‐butylphenyl) porphyrin, 5,15‐(dimesityl) porphyrin, and 5,15‐(di‐4‐ethynylphenyl) porphyrin. Scanning tunneling microscopy and density functional calculations reveal that 5,15‐(di‐3,5‐di‐tert‐butylphenyl) porphyrin, 5,15‐(dimesityl) porphyrin, and 5,15‐(di‐4‐ethynylphenyl) porphyrin spontaneously give different ordered structures on Ag(110) surface both at room temperature and after annealing. It is clear that the tert‐butylphenyl substituent could increase the intermolecular van der Waals interactions to form stable network structure under condition of thermal activation, whereas the mesityl substituent plays an essential role in the formation of rigid chain structure as a result of the CH–π interactions between the mesityl groups of molecule enantiomers. Moreover, the ethynylphenyl substituent could induce metal atoms to coordinate with ethynyl to form organometallic chains. Copyright © 2016 John Wiley & Sons, Ltd.     

不同类型卟啉自组装膜的制备及表征

制备了不同类型的巯基卟啉自组装膜,借助多种表征技术（紫外可见光谱、电化学和X射线光电子能谱）研究了不同类型卟啉自组装膜的结构特点;研究结果表明,卟啉分子中巯基取代基数目的不同（-[SH]n-,n=1,4）,导致了卟啉环在自组装膜表面的构型不同,从而表现出不同巯基卟啉自组装膜性能的差异。 在此基础上,提出了不同巯基卟啉自组装膜的结构模型。     

A Nanoemulsion with A Porphyrin Shell for Cancer Theranostics

A nanoemulsion with a porphyrin shell (NewPS) was created by the self‐assembly of porphyrin salt around an oil core. The NewPS system has excellent colloidal stability, is amenable to different porphyrin salts and oils, and is capable of co‐loading with chemotherapeutics. The porphyrin salt shell enables porphyrin‐dependent optical tunability. The NewPS consisting of pyropheophorbide a mono‐salt has a porphyrin shell of ordered J‐aggregates, which produced a narrow, red‐shifted Q‐band with increased absorbance. Upon nanostructure dissociation, the fluorescence and photodynamic reactivity of the porphyrin monomers are restored. The spectrally distinct photoacoustic imaging (at 715 nm by intact NewPS) and fluorescence increase (at 671 nm by disrupted NewPS) allow the monitoring of NewPS accumulation and disruption in mice bearing KB tumors to guide effective photodynamic therapy. Substituting the oil core with Lipiodol affords additional CT contrast, whereas loading paclitaxel into NewPS facilitates drug delivery.     

形貌可控卟啉材料的合成及光电性质

通过自组装方法制备了一种卟啉材料,并通过调节溶液pH值实现了对其形貌的可控。 当pH值较低时形成卟啉棒状结构;当pH值较高时形成卟啉叶片状结构。 利用紫外、红外和X衍射仪等多种表征方法对其结构和性质进行了表征。 结果表明,在无机酸的作用下,卟啉分子通过π-π、静电作用形成一维结构的J-聚集体;当pH值增加时,氢键的作用占主要作用形成二维片状结构。 将此卟啉棒状材料构筑微纳米器件,测试其光电性能,表明对可见光有很好的响应。 这种具有光电响应的卟啉材料有望成为微纳电子器件的光电元件。     

氮杂苯并菲类n-型有机半导体材料研究进展

苯并菲盘状液晶是一类新型的有机电子学材料.该类材料多数以空穴传输功能为主,能传输电子的n-型材料较少.氮杂苯并菲是与苯并菲衍生物非常相似的一种杂环化合物,材料结构中引入了氮原子,吸电子能力得到增强,是潜在的n-型有机半导体材料,具有重要的应用价值.本文系统回顾了氮杂苯并菲类盘状液晶材料的研究进展,分类讨论了材料的分子结构,其中包括二、四、六氮杂苯并菲,以及它们的合成方法和物理化学性能,论述了材料在光电子领域的最新使用进展,并在此基础上,对该类液晶材料作为n-型有机半导体在光电子器件领域的应用前景进行了展望.