【作者】 吕伟；

【导师】 姜建壮；

【作者基本信息】 山东大学 ， 无机化学， 2010， 博士

【摘要】 手性是自然界和生命体中普遍存在的现象,手性分子识别及自组装是许多生物化学现象的本质。研究手性分子的合成、组装及构效关系可以用来模拟生命过程中的手性识别与手性的相互作用,对于从分子水平上模拟生物功能,研究生物体内各种生物现象具有重要意义。卟啉酞菁化合物以及三明治型稀土卟啉酞菁配合物作为新型的功能材料,由于其具有迷人的、独特的光学、电学、磁性以及其它的与其分子内部大环之间π-π相互作用有关的物理性质,因此使得它们在分子电子学、分子信息存储和非线性光学上具有潜在的应用价值,在材料科学领域拥有广阔的应用前景。因此对于手性四吡咯大环衍生物的设计合成及其组装的研究也将具有重要的科研和应用价值。近年来,手性卟啉酞菁配合物的有序超分子聚集体和纳米尺度组装研究已经成为了热点领域。但是,到目前为止,对手性卟啉酞菁配合物的报道还很少。本论文主要主要设计、合成了具有特定分子结构和特殊性质的新型手性酞菁及其衍生物,通过自组装方法,将上述合成的目标化合物组装成各种高级有序的聚集体材料,探讨组装过程的机理和动力学过程,研究分子结构对分子在聚集体中排列方式的影响以及聚集体结构和性质之间的关系,总结变化规律,系统的总结研究各种具有更高性能的新型分子功能材料的思路和方法。此外,本论文还研究了分子水平上三明治型酞菁类配合物分子内手性信息的传递和表达,为从该类大环配合物的分子结构和电子结构的层面上研究手性产生机制,总结变化规律,探讨设计合成新型光学活性分子提供了重要的思路和方法。其内容主要包括以下几个部分：1、光学活性自由酞菁的合成及其自组装纳米级空心球结构的研究有机功能分子自组装得到的有序纳米结构被预期在纳米科学与纳米技术中获得广泛的应用。自组装过程是一种自发的过程,是指分子间通过非共价键例如,氢键、配位键、堆积效应、静电相互作用、亲／疏水相互作用等形成的结构稳定、复杂有序且具有某种特定功能的纳米聚集体或超分子结构的过程。由各种分子材料制备得到的各种各样形貌的自组装有机纳米结构的报道层出不穷：纳米线、纳米棒、纳米颗粒和纳米管等等。然而,对化学家和材料学家来说,通过模拟和设计分子的结构调节分子间作用力以获得所希望的有机纳米结构材料的形貌仍然是一个挑战。在本章中,通过分子设计、合成和表征,我们研究了一种新颖的由四个辛基链通过两个联萘基团连接到酞菁分子环上的光学活性自由酞菁分子(1),利用相转移方法,通过组装成有机纳米聚集体,利用紫外(UV)、红外(FT-IR)、透射电镜(TEM)、扫描电镜(SEM)等表征手段系统比较研究了该分子在添加表面活性剂(CTAB)和不加表面活性剂(CTAB)两种情况下的自组装性质。研究结果表明,酞菁环非周边位置两个位阻较大的联萘基团的引入不仅将光学活性引入到酞菁大环,而且空间位阻的存在降低了相邻酞菁分子间的π-π相互作用。同时,联萘基团周边四个辛基长链的引入增强了自由酞菁分子(1)和CTAB分子间的疏水相互作用。因此,该自由酞菁分子自组装为纳米颗粒的形貌。恰恰不同的是,加入CTAB后,该自由酞菁分子组装得到了纳米级空心球的形貌。该工作是第一例由酞菁化合物制备的有机纳米级空心球结构,为酞菁化合物制备纳米级空心球结构提供一条新的有效参考途径。2、手性孟醇取代自由酞菁的设计、合成、和自组装纳米螺旋纤维结构的研究共轭分子体系自组装形成的各种不同结构稳定且复杂有序的纳米聚集体主要是通过分子间π-π键和其它非共价键的协同作用所得到的。所以,人们通常在共轭分子体系周围引入不同的功能基团来改变共轭分子的结构来调节它们之间的作用进而控制自组装纳米结构的形貌。由于生物大分子及超分子具有美妙的螺旋结构,为了更好地了解并利用这些现象,人类依靠非共价作用获得了大量结构可控的螺旋状超分子。近些年来,由于具有螺旋状结构的π共轭分子在仿生学、化学传感器、催化剂及光化学器件方面具有潜在的应用价值,对于它们结构的精确控制吸引了越来越多的关注。具有光化学活性的酞菁组装成的螺旋超分子结构吸引了广泛的研究兴趣,而这正是由于其不仅可作为智能软纳米材料运用在数据存储和处理领域、也可作为螺旋蛋白质结晶的手性模板手性,还可用于传感器、生物光电设备、手性光学设备、催化以及生物化学等方面。基于上述原因,人们合成了大量含有手性取代基的酞菁化合物并试图将其构建成各式的超分子结构。关于手性酞菁衍生物的研究报道是最近十几年才出现的；而对于手性酞菁分子的超分子组装研究则是从1999年才开始的。R. J. M. Nolte在science上报道了具有手性侧链冠醚结构的酞菁在溶液中的自组装,形成了具有螺旋结构的纤维。在本文中,我们首次详细的描述了一种新颖的自由酞菁化合物(D)-／(L)-2(3),9(10),16(17),23(24)-四(2-异丙基-5-甲基环己氧基)酞菁分子的设计、合成、表征、及其自组装性质。原本该酞菁分子在CD光谱(圆二色谱)上不表现分子手性,但当往该酞菁分子的氯仿溶液中加入一定量的甲醇时,由于酞菁环之间强的分子间π-π相互作用,以及手性侧链中多个手性中心的手性识别作用,使自组装过程中手性孟醇取代基对中心酞菁发色团的不对称振动增强,从而在氯仿和甲醇的混合溶剂中发生分子内手性传递,分级组装形成高级有序的手性纤维状纳米结构(既有左旋也有右旋),使手性在超分子层次得到了表达。该项研究结果代表我们对分子设计与合成的前提下制备自组装螺旋纳米结构的继续努力,它将为研究人工合成共轭体系在超分子水平上手性信息传递和表达提供有益的帮助,对通过分子设计和合成得到可控的分子堆积模式和纳米形貌有着很好的指导作用。3、联二萘酚取代金属锌酞菁可控形貌的纳米级自组装性质的研究由于在纳米科学和纳米技术方面的众多应用,将有机功能分子自组装为形貌可控的纳米结构吸引了人们越来越多的研究兴趣。在各种非共价键相互作用的基础上,人们由大量功能分子制备得到各种各样的纳米结构如纳米线、纳米带、囊泡、纳米管等。其中,纳米空心球结构因其在药物传递、化学存储、光纤维、化学催化、以及制备功能结构复合材料的模板等众多方面的潜在应用而被广泛关注。酞菁(Pc)由于独特的大环平面、刚硬的分子结构以及电子特征,展示了迷人的光谱性质、光物理性质、光化学性质和自组装性质。作为理想的非共价键超分子体系构筑单元,酞菁可用于制备分子水平上的电子、光学器件如电子线、电子开关、电致发光装置、场效应晶体管、光电装置等,因而被倾注了越来越多的研究兴趣。尽管有丰富的非共价作用作为工具,对于化学家和材料科学家来说,理解各种非共价作用的协同作用对控制和调节有机自组装纳米结构的形貌和尺寸的影响依然是个挑战。本文中我们对比研究了典型的芳环共轭体系金属锌酞菁化合物Zn{Pc(OBNP)2)在添加DABCO之前和之后的自组装性质。结果表明除了π-π相互作用,金属配位键的协同作用导致溶液中不同的分子堆叠方式,从而在自组装过程中产生了不同形貌的纳米结构。酞菁锌化合物Zn{Pc(OBNP)2)的氯仿溶液中,酞菁锌分子间π-π相互作用导致形成了纳米级空心球结构。往溶液中加入DABCO后,酞菁锌分子中的金属锌离子与DABCO中未饱和的氮原子配位,形成Zn-NDABCO配位键,协同于π-π相互作用,形成了不同于空心球形貌的纳米带。研究结果表明非共价相互作用如π-π相互作用和金属配位作用间的协同作用在控制和调节酞菁化合物自组装形貌中起了非常重要的作用。本部分的工作代表了我们在阐明各种非共价作用(π-π相互作用、金属配位作用等)的协同作用和控制、调节酞菁化合物自组装纳米形貌之间相互关系方面的努力,同时也为我们通过分子修饰制备形貌可控的纳米级自组装结构提供了有益帮助。由于酞菁化合物丰富的光、电、化学性能,作者期望本文的研究结果有助于分子水平的纳米级电学、光学性能的开发。4、光学活性卟啉酞菁双层稀土金属配合物的合成、表征及及分子水平上手性信息传递和表达的研究最近几年,手性三明治型卟啉酞菁稀土金属化合物由于其特殊的结构、性质、以及在大量信息存储和处理的纳米级软材料、以手性结构为模板的螺旋纳米晶体(蛋白质等)、手性传感、光生物电子学、手性光学装置、催化剂、生物化学等众多方面的潜在应用,其合成和性质研究引起人们越来越多的研究兴趣。两个或三个四吡啶基通过一个或两个稀土金属离子连接起来的特殊分子结构使这些稀土配位多面体具有特殊的四方反棱柱几何结构,使这些化合物有可能通过各种不同特殊对称性的卟啉酞菁配合基获得手性。除了利用手性拆分的方法制备手性三明治型酞菁卟啉金属配合物外,还可以利用含非中心对称G2v对称性π-体系的手性分子为原料合成光学活性的三明治型配合物。据我们所知,周边取代基中含手性碳的光学活性的三明治型酞菁卟啉金属配合物至今依然很少。到目前为止,在分子水平上,手性碳原子的手性很难传递到卟啉、酞菁等大环配合物上。在本章中,我们描述了一系列新颖的β位手性孟醇四取代对称酞菁双层稀土配合物(D)-和(L)-M(Pc*)2[M=Eu(1),Y(2),Lu(3)]和不对称酞菁双层铕配合物(D)-和(L)-Eu(Pc)(Pc*)(4).尽管Eu(Pc)(Pc*)(4)在酞菁配合基的Soret带和Q带吸收区域都不显示CD信号,但两个对映体(D)-和(L)-4都在孟醇的电子吸收区域显示了CD信号。随着酞菁周边孟醇取代基数目的增加,对称酞菁双层稀土配合物M(Pc*)2(1-3)的(D)-和(L)-对映体都在酞菁配合基的Soret带和Q带吸收区域显示CD信号。第三章中我们已经知道自由酞菁(D)-和(L)-2(3),9(10),16(17),23(24)-四(2-异丙基-5-甲基环己氧基)酞菁在酞菁配合基的整个电子吸收区域都不显示CD信号,比较之下可以清楚的说明强烈的分子内π-π相互作用对增强手性取代基的不对称振动从而导致分子水平上手性信息的传递和表达有重要作用。该研究结果代表我们设计和制备手性三明治型稀土配合物的努力之一,它将为研究分子水平共轭体系手性信息传递和表达提供新视野。我们还报道了第一例光学活性的混杂三明治型酞菁卟啉稀土金属配合物[MⅢH{Pc.(OBNP)2)(TClPP)](M=Y(1),Eu(2)；OBNP-联二萘,TClPP=meso-四(4-氯苯基)-卟啉)的合成和表征。为了通过偶极-偶极作用增强对混杂三明治型稀土酞菁和卟啉双层中四吡咯大环发色团的不对称扰乱,手性联二萘酚基团被引入到酞菁环的非周边位置。结合电子吸收光谱和磁圆二色谱(MCD)的结果,圆二色谱(CD)技术证明混杂三明治型卟啉酞菁稀土金属配合物在不同溶剂中有不同的构象,从而显示不同的光谱性质。基于(S)-[YⅢ{Pc-(OBNP)2)(Por)]-两个大环配体之间的扭转角不同,根据时间密度函数理论(TDDFT)计算结果,(S)-[HYⅢ{Pc(OBNP)2)(TClPP)]在DMF和CHCl3中也同样产生了不同的电子吸收光谱和CD光谱性质,这些现象显示溶剂诱导的混杂三明治型酞菁卟啉稀土金属配合物分子构象的改变。当前的工作揭示了混杂三明治型卟啉酞菁稀土金属配合物的光谱性质随着溶剂的改变(DMF和CHCl3)而发生的改变是由于双层配合物分子与溶剂分子之间的相互作用不同,导致双层配合物分子的构象改变。据我们所知,这是第一例对溶剂诱导的三明治型双层四吡咯大环金属配合物光谱性质改变的解释。更多还原

【Abstract】 Chirality is one of the most fascinating and complicated features commonly found in nature. Inspired by the elegance of biological supramolecular structures, numerous artificial helical supramolecular structures with controlled helicity have been developed depending on various non-covalent interactions. Owing to the unique optical, electrical, and properties, associated with the intriguing intramolecularπ～πinteractions, porphyrins, phthalocyanines, as well as sandwich type rare complexes, as a novel functional materials, have been expected to be widely potential application in materials science, such as in molecular electronics, molecular information storage, and nonlinear optics, etc. Recently, it is significantly interested in ordered supramolecular aggregate and nanoscale assembly fields. However, it must be pointed out that self-assembly of chiral functional molecules into a prerequisite nanostructure with desirable dimension and morphology via controlling and optimizing inter-molecular interaction still remains a great challenge for chemists and material scientists. In order to extensively investigate supramolecular aggregation behaviors and supramolecular assembly methodology of chiral phthalocyninato complexes, in this thesis a series of chiral phthalocyanine derivatives are selected, and some modern measuring techniques were performed to examine their aggregate structures, morphologies and nanostructures. Our research work has been focused on the following respects:1. Synthesis and Novel Hollow Sphere Nanostructures of Optically Active Metal-free PhthalocyanineNovel optically active metal-free phthalocyanine (1) decorated with four octyl chains linked via binaphthyl units to the phthalocyanine ring was designed and prepared. This new compound was characterized by a wide range of spectroscopic methods in addition to elemental analysis. By employing a solution injection method, both (R)-and (S)-enantiomers self-assemble into nano-particles. Surprisingly, with the addition of small amount of cetyltrimethylammonium bromide (CTAB), nanostructures with hollow sphere morphology were formed. The hollow spherical structure was determined by transmission electronic microscopy (TEM) and scanning electronic microscopy (SEM). X-ray photoelectron spectroscopy (XPS) together with FT-IR spectra indicates the supramolecular structures formed from the metal-free phthalocyanine molecules. Low-angle X-ray diffraction (XRD) reveals the stacked phthalocyanine molecules with a face-to-face configuration in the nanoscale hollow spheres formed with the help of CTAB surfactant. The formation of H-aggregates in the nanoscale hollow spheres is further confirmed by electronic absorption spectroscopic result. This work, representing the first example of controllable organic nanostructures with hollow sphere morphology fabricated from phthalocyanine compound, provides an effective method towards phthalocyanine nano-hollow spheres.2. Helical Fibrous Nano-structures Self-assembled from Metal Free Phthalocyanine Bearing Four Peripheral Chiral Menthol Moieties(D)-and (L)-enantiomers of a novel metal free 2(3),9(10),16(17),23(24)-tetrakis(2-isopropyl-5-methylcyclohexoxyl)phthalocyanine (1) with four chiral menthol units attached at the peripheral positions of phthalocyanine ligand have been designed, synthesized, and characterized. Neither (D)-1 nor (L)-1 enantiomer displays CD signal in the Soret and Q absorption region of phthalocyanine ligand, indicating the lack of effective chiral information transfer from the chiral menthol tails to phthalocyanine chromophore at the molecular level. Their self-assembly properties were systematically studied by circular dichroism (CD) spectra, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atom force microscopy (AFM) technique. Despite the composition of four constitutional stereoisomers of each enantiomer due to the random location of four chiral menthol substituents at the peripheral positions of phthalocyanine ring, cooperation of inter-molecularπ-πinteraction between phthalocyanine rings with chiral discrimination of chiral side chains of (D)-1 and (L)-1 enantiomer induces the formation of one-dimensional helices with left-handed and right-handed helical molecular arrangement, respectively, according to the CD spectroscopic result. This reveals the effective chiral information transfer from the chiral menthol tails to phthalocyanine chromophore at the supermolecular level. The formed one-dimensional helices twist around each other to maximize the van der Waals interaction, leading to the formation of highly ordered fibrous nano-structures with both right-handed and left-handed helicity according to the staggering angles between the neighboring phthalocyanine molecules, indicating the hierarchical formation of these fibrous nano-structures. Careful inspection over these nano-fibers indicates the majority of nano-fibers with right-handed and left-handed helicity formed from (D)-1 and (L)-1 enantiomer, respectively, with the ratio of ca.1.3-1.4:1 among all the fibrous nano-structures obtained. Electronic absorption spectroscopic and X-ray diffraction (XRD) results reveal the H-aggregate nature of these nano-fibers. The present result, representing part of our continuous effort towards preparation of self-assembled nano-structures with helical morphology through molecular design and synthesis, will be helpful on providing new insight into chiral information transfer and expression for synthetic conjugated systems at supermolecular level.3. Tuning the Morphology of Self-Assembled Nano-structures of Phthalocyaninato Zinc Complex Bearing Two Non-peripheral binaphthyl Units Self-assembly of functional organic molecules into well-defined organized nano-structures has recently attracted considerable research interest due to their versatile applications in nanoscience and nanotechnology. On the basis of different non-covalent interactions, a wide variety of nano-structures such as wires, belts, vesicles, and tubes have been fabricated from various functional molecules. For example, hollow spheres represent an appealing class of nano-structures due to their many potential applications in drug delivery, chemical storage, light filters, chemical catalysis, and as template for preparing functional architectural composite materials. Due to their unique planar and rigid molecular geometry and aromatic electronic feature delocalized over the molecular frame, phthalocyanines exhibit intriguing, peculiar, and tunable spectroscopic, photophysical, photochemical, and assembly properties. By virtue of these excellent features, phthalocyanines have received extensive research interests as ideal building blocks for the construction of non-covalent linked supramolecular assemblies with motivation for preparation of molecular-based electronic and optical devices such as electronic wires, switches, electroluminescence devices, field-effect transistors, and photovoltaic devices. Despite of the accessibility to a rich toolbox of noncovalent interactions, it still remains a great challenge for chemists and material scientists to understand the effect of synergistic interplay of different non-covalent interactions on controlling and tuning the desirable dimension and morphology of organic self-assembled nano-structures. In the present paper, we comparatively studied the self-assembly properties of phthalocyaninato zinc complex Zn{Pc(OBNP)2} with or without equal amount of DABCO. Comparative investigation results reveal that besides theπ-πinteraction, cooperation of metal-ligand coordination bonding lead to different molecular packing information and in turn different nano-structure morphology in the self-assembly process. Intermolecularπ-πinteraction of phthalocyaninato zinc complex Zn{Pc(OBNP)2} leads to the formation of nano-scale hollow spheres. Additional dominant Zn-NDABCO coordination bond between the nitrogen atom of DABCO molecule and the zinc center of the phthalocyaninato zinc molecule, together withπ-πinteraction leads to the formation of nano-belts for this complex, indicating the effect of synergistic interplay among non-covalent interactions such asπ-πinteraction and metal-ligand coordination bonding in controlling and tuning the morphology of self-assembled nano-structures of phthalocyanine compounds. The present study represents part of our continuous efforts towards understanding the synergistic interplay between non-covalent interactions on controlling and tuning the morphology of self-assembled nano-structures of phthalocyanine derivatives, and provides information helpful on preparing self-assembled nano-structures with controlled molecular packing conformation and morphology through molecular modification. Owing to the rich optical, electrical, and chemical properties of phthalocyanine derivatives, they are believed to be helpful in opening new possibilities for construction of molecular-based nano-electronics and nano-optoelectronics.4. Optically Active Homoleptic Bis(phthalocyaninato) Rare Earth Double-Decker Complexes Bearing Peripheral Chiral Menthol Moieties:Effect ofπ-πInteraction on the Chiral Information Transfer and Expression at the Molecular Level(D)-and (L)-enantiomers of a series of optically active homoleptic bis(phthalocyaninato) rare earth double-deckers with four chiral menthol moieties at the peripheral positions of phthalocyanine ligand, M(Pc*)2 [Pc*= 2(3),9(10),16(17),23(24)-tetrakis(2-isopropyl-5-methylcyclohexoxyl)phthalocyanine; M= Eu (1), Y (2), Lu (3)] have been designed and prepared by treating (D)-or (L)-4-(2-isopropyl-5-methylcyclohexoxyl)-1,2-dicyanobenzene with the corresponding M(acac)3·nH2O (acac=acetylacetonate) in the presence of organic base 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in refluxing n-pentanol. For the purpose of comparative study, heteroleptic bis(phthalocyaninato) europium analogues (D)-and (L)-Eu(Pc)(Pc*) (4) as well as the unsubstituted homoleptic bis(phthalocyaninato) europium counterpart Eu(Pc)2 (5) were also prepared. The novel synthesized bis(phthalocyaninato) rare earth double-deckers have been characterized by a wide range of spectroscopic methods including MS,1H NMR, IR, and electronic absorption spectroscopic measurements in addition to elemental analysis. In contrast to the findings that no CD signal was detected in the absorption region for the monomeric metal free (D)-and (L)-2(3),9(10),16(17),23(24)-tetrakis(2-isopropyl-5-methylcyclohexoxyl)phthalocyanine, observation of the CD signal in the menthol absorption region of 4 reveals the significant effect of intense intra-molecularπ-πinteraction on intensifying the asymmetrical perturbation of the chiral menthol units and resulting in the chiral information expression by menthol moieties of 4 at molecular level despite the lack of CD signal in the Soret and Q absorption region of phthalocyanine ligand. This is further supported by the optical activity for homoleptic bis(phthalocyaninato) rare earth double-deckers M(Pc*)2 (1-3) revealed even in the Soret and Q absorption region of phthalocyanine ligand according to the CD spectroscopic result. Along with the increase in the chiral menthol substituent number, the further intensified asymmetrical perturbation induces the effective chiral information transfer from the peripheral chiral menthol side chains even to the phthalocyanine chromophore of 1-3, indicating the effect of chiral substituent number on the chiral information transfer and expression at the molecular level. In addition, their electrochemical properties have also been comparatively investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV).We also report the preparation and characterization of the first optically active mixed (phthalocyaninato)(porphrinato) rare earth complexes [HMⅢ{Pc(OBNP)2}(TClPP)] (M=Y, Eu) (1,2), Scheme 1. To enhance the asymmetric perturbation to the tetrapyrrole chromophores in the sandwich-type mixed (phthalocyaninato)(porphyrinato) rare earth double-decker molecules through dipole-dipole interaction, aromatic chiral binaphthayl units were introduced onto the non-peripheral positions of phthalocyanine ring. In addition to electronic absorption and MCD spectroscopic results, CD technique reveals obvious different spectroscopic feature of these mixed ring rare earth double-decker compounds in different solvent. On the basis of time-dependent density functional theory (TDDFT) calculation results on the yttrium species (S)-[YⅢ{Pc(OBNP)2}(Por)]- in terms of different rotation angle between the two macrocyclic ligands in the double-decker molecules, different electronic absorption and CD spectroscopic feature of (S)-[HYⅢ{Pc(OBNP)2}(TClPP)] in DMF and CHCl3 was well reproduced, revealing the solvent-dependent nature on the molecular conformation of mixed ring rare earth double-decker complexes. The present work reveals the change in optical spectroscopic spectra of mixed (phthalocyaninato)(porphyrinato) rare earth complexes along with solvent change from DMF to CHCl3 due to the change in the double-decker molecular conformation associated with different interaction between double-decker and solvent molecules. This, to the best of our knowledge, represents the first effort on understanding the nature of optical spectroscopic change of bis(tetrapyrrole) metal complexes depending on solvent.更多还原