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卟啉酞菁化合物的设计、合成、表征及自组装性质的研究

Design, Synthesis, Characterization and Self-assembly Properties of Porphyrinato/Phthalocycaninato Complexes

【作者】 逯纪涛

【导师】 姜建壮;

【作者基本信息】 山东大学 , 无机化学, 2011, 博士

【摘要】 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,由于其具有迷人的光学、电学、磁学性能而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。近年来,该类配合物的高度有序的纳米结构由于在光电子分子器件方面的潜在应用价值而吸引了广泛的研究兴趣。但是,如何通过调节分子之间的弱的相互作用力来控制有机纳米聚集体的形貌以及尺寸对化学工作者来说,仍然是一个相当大的挑战。本论文主要设计、合成了具有特殊分子结构的新型卟啉酞菁配合物,对它们进行了详细的表征并研究了它们的自组装性质,讨论了各种弱的相互作用力对分子在聚集体中的排列方式的影响以及对聚集体形貌的影响。其内容主要包括以下几个部分:1.手性卟啉化合物组装螺旋纳米结构的研究近年来,卟啉及其衍生物的自组装行为和纳米结构在构建分子水平上的电子和光学器件,例如,分子导线、电子开关、电致发光装置、场效应晶体管以及光伏器件等方面的众多应用而引起了广泛的研究兴趣。在这些广泛研究的基础上,由卟啉衍生物尤其是手性卟啉衍生物制备得到的螺旋和手性的超分子结构由于具有广阔的应用前景,因而吸引了研究者的浓厚研究兴趣。基于上述原因,大量含有各种不同手性中心的手性卟啉化合物被合成出来,如含有手性氨基酸或手性糖类或烃类基团的卟啉化合物。然而大量研究表明,手性基团修饰的卟啉分子并不是都能组装成螺旋超分子结构,事实上仅有一部分卟啉化合物得到了螺旋超分子结构。此外,还有部分卟啉化合物的超分子聚集态虽然可以测得圆二色信号,但是得不到具有螺旋形貌的纳米结构。这可能是由于分子间的作用力太弱以至于没有得到足够的长呈有序结构。因而,非共价键的作用力和手性识别之间脆弱的平衡在制备螺旋纳米结构的过程中发挥了非常重要的作用。但是非共价键作用力和手性识别在卟啉化合物的自组装过程中对形成的聚集体的形貌和尺寸所起到的作用依然不是很清晰。在本章中我们设计、合成并表征了一种新型具有光学活性的卟啉化合物(1),并对该化合物的自组装过程进行了系统研究。研究表明,在不加入钾离子的的状态下该卟啉化合物自主装的形貌是纳米球。当加入钾离子后,由于钾离子和冠醚之间的配位作用以及卟啉外围的手性基团的手性识别的协同作用,该卟啉化合物自组装得到的形貌是螺旋状的纳米线。这项研究将为在超分子层次上研究手性信息传递提供很好的指导作用。2.光学活性的混杂三层卟啉酞菁稀土金属配合物的合成、表征及分子水平上手性信息的传递和表达手性是自然界中最为迷人也最为复杂的现象之一。受一些天然手性生物分子所展现的特殊功能和性质的启发,利用不对称合成的方法,大量手性化合物包括具有光学活性的卟啉酞菁类配合物被化学科学家合成出来。但是到目前为止,报道的具有手性光学活性的三明治型卟啉酞菁类化合物依然很少。1997年,Aida及其合作者报道了D2对称性的手性卟啉双层锆和铈配合物的合成和手性拆分,这些配合物可以作为金属离子、羧酸以及糖类化合物的受体。Shinkai课题组通过手性二羧酸或糖类与双[四(4-吡啶基)卟啉]铈配合物中吡啶氮原子的氢键结合将手性引入双层卟啉铈配合物。Jiang的课题组报道了利用手性HPLC技术结合利用L-Boc-Phe-OH作为手性解析试剂形成非对映异构体混合物,对不对称卟啉酞菁双层稀土配合物[HMⅢ{Pc(α-3-OC5H11)4}{TOAPP}][Pc(a-3-OC5H11])4=1,8,15,22.四(3-戊氧基)-酞菁;TOAPP=meso-四(4-辛胺基-苯基)卟啉;M=Y, Ho]成功进行了手性拆分。不仅通过酞菁配体的面不对称性可以成功地将手性诱导到混杂卟啉酞菁双层配合物上,在酞菁外围修饰上具有光学活性的芳香族基团后也能成功的将光学活性诱导到混杂卟啉酞菁双层配合物上。受这一结果的启发,我们设计、合成并表征了两种新型卟啉酞菁三层配合物[M2(Pc)2(TCBP)]{TCBP= Meso - tetrakis [3,4-(11,12:13,14-bis(1’,2’-naphtho)-1,4,7,10,15,18-hexaoxacycloeicosa-2,11,13-triene)-phe nyl]porphyrinate;M=Eu(1),Y(2)}.CD测试结果表明,由于卟啉和酞菁环之间存在强烈的π-π相互作用,手性信号成功的从手性联二萘酚诱导到了卟啉和酞菁生色团的soret和Q带上。据我们所知,到目前为止这一研究是报道的第一例具有光学活性的混杂卟啉酞菁三层稀土金属配合物。3.三明治混杂卟啉酞菁三层稀土金属配合物自组装纳米结构的研究有机功能分子自组装成有序的纳米结构在先进功能分子材料方面的众多潜在应用价值而引起了化学家的广泛关注。各种非共价键例如,π-π堆积效应、范德华力、氢键、亲疏水作用、静电作用、金属配位键等是有机功能分子自组装成有序纳米结构的主要驱动力。基于这些作用力,各种各样形貌的有机纳米结构的报道层出不穷:纳米线、纳米带、纳米囊泡、纳米管、纳米球等等。在这些有机功能分子中,共轭分子体系由于在传感器、场效应晶体管以及光化学方面的广泛潜在应用而被认为是构筑超分子自组装纳米分子体系的最佳分子体系。在本文中,作为我们对卟啉酞菁类配合物纳米聚集体的进一步研究,我们合成了一个混杂卟啉酞菁三层稀土金属化合物,Eu2Pc2(TClPP)(1)并研究了它的晶体结构以及它在溶液中的自组装性质,并利用它的晶体结构对其自组装的机理成功进行了解释。这为开发和探索新型分子功能器件的制备提供了一条新的参考途径。4.模板法制备三明治混杂卟啉酞菁三层稀土金属配合物纳米管由于有机纳米聚集体独特的的电子和光学性质,近年来将一些有机大分子组装成有序的纳米结构吸引了化学工作者的极大兴趣,尤其是一维的纳米聚集体因为它们广泛的潜在应用最近成了材料化学的研究热点。因此大量的一维纳米结构通过不同的制备方法和用不同的材料被制备出来,例如纳米纤维、纳米带、纳米管等。在这些大量的制备一维结构的方法中,由于模板法尤其是氧化铝模板法制备的一维纳米结构排列有序以及纳米结构的尺寸一致而吸引了广泛的关注。通常来说,这种分子高度排列以及聚集体大面积有序排列的一维纳米聚集体被一致认为可以用于纳米器件的制备。本章中我们通过氧化铝模板法将酞菁β位修饰有不同长度烷氧基链的卟啉酞菁三层配合物,Eu2(Pc)2(TClPP) (1), Eu2[Pc(β-OC4H9)8]2(TClPP) (2),和Eu2[Pc(β-OC8H17)8]2(TClPP)(3),制备成了一维的纳米管聚集体。系统的研究表明,在卟啉酞菁三层配合物的外围修饰上不同的取代基后影响了分子在纳米管聚集体中的排列方式。这部分工作我们研究了分子的结构对分子在聚集体中的排列方式的影响从而为进一步研究更高性能的新型功能分子材料提供新的思路和方法。

【Abstract】 Owing to the intriguing optical, electrical, and properties, 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, well-defined nanostructures have attracted increasing attentions due to their potential applications in (opto)electronic molecular devices. However, it must be pointed out that self-assembly of 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 this thesis, a series of porphyrin and/or phthalocyanine derivatives have been designed, synthesized, characterized, and some modern measuring techniques were performed to examine the influence of the noncovalent interactions such as hydrogen bonding, metal-ligand coordinate bonding, electrostatics, van der Waals, andπ-πstacking between the adiacent molecules on formation of their aggregate morphologies. Our research work has been focused on the following respects:1. Helical Nanostructures of Optically Active Metal Free Porphyrin with Four Optically Active Binaphthyl Moieties. Effect of Metal-ligand Coordination on the MorphologyNovel optically active metal free porphyrin (1) with four chiral binaphthayl units attaching at the meso-phenyl substituents through crown ether moieties has been designed, synthesized, and characterized. Their self-assembly behavior in the absence and presence of K+ was comparatively investigated by electronic absorption and circular dichroism (CD) spectra, transmission electron microscopy (TEM), scanning electron microscopy (SEM), atom force microscopy (AFM), and energy-dispersive X-ray (EDX) spectroscopy. In the absence of K+, metal free porphyrin self-assembles into nano-particles depending mainly on the van der Waals interaction among neighboring metal free molecules. In the presence of K+ additionally formed metal-ligand K-Ocrown coordination bonds between K+ and crown units of (R)-and (S)-1 molecule together with chiral discrimination of chiral side chains and intermolecular van der Waals interaction induce respectively a right-handed and left-handed helical arrangement in a stack of (R)-and (S)-1 molecules with an ordered "head-to-tail" internal molecular arrangement, which then further hierarchically self-assembles into highly ordered fibrous nanostructures with the opposite helicity to the original porphyrin stack. This clearly reveals the effect of metal-ligand coordination bonding interaction on the morphology and handedness of self-assembled nanostructures.2. Optically Active Mixed (Phthalocyaninato)(porphyrinato) Rare Earth Triple-decker Complexes. Synthesis, Spectroscopy, and Effective Chiral Information TransferWith the view to creating novel sandwich-type tetrapyrrole rare earth complexes towards potential applications in material science and chiral catalysis, two new optically active mixed (phthalocyaninato)(porphyrinato) rare earth triple-decker complexes with both (R)-and (S)-enantiomers [M2(Pc)2(TCBP)] {TCBP= Meso-tetrakis [3,4-(11,12:13,14-di(1’,2’-naphtho)-1,4,7,10,15,18-hexaoxacycloeicosa-2,11,13-triene)-phen yl] porphyrinate; M=Eu (1), Y (2)} have been designed and prepared by treating optically active metal free porphyrin (R)-/(S)-H2TCBP with M(Pc)2 in the presence of corresponding M(acac)3·nH2O (acac=acetylacetonate) in refluxing 1,2,4-trichlorobenzene (TCB). These novel mixed ring rare earth triple-decker compounds were characterized by a wide range of spectroscopic methods including MS,1H NMR, IR, electronic absorption, and magnetic circular-dichroism (MCD) spectroscopic measurements in addition to elemental analysis. Perfect mirror image relationship was observed in the Soret and Q absorption regions in the circular-dichroism (CD) spectra of the (R)-and (S)-enantiomers, indicating the optically active nature of these two mixed (phthalocyaninato)(porphyrinato) rare earth triple-decker complexes. This result reveals the effective chiral information transfer from the peripheral chiral binaphthyl units to the porphyrin and phthalocyanine chromophores in the triple-decker molecule due to the intenseπ-πinteraction between porphyrin and phthalocyanine rings.3. Synthesis, Crystal Structure and Self-assembly Property of A Mixed (Phthalocyaninato)(porphyrinato) Europium Triple-decker ComplexA mixed phthalocyaninato and porphyrinato triple-decker complex [Eu2(Pc)2(TClPP)] was synthesized and characterized by elemental analysis, FT-IR, UV, and X-ray structure determination. Its self-assembling properties in mixed chloroform/methanol solution were investigated by TEM, SEM and XRD technique. Investigation reveal the availability single crystal, together with the molecular structure, renders it possible to investigate the formation mechanism as well as the molecular packing conformation of self-assembled nano structures fabricated from this complex in a more confirmed manner.4. Sandwich-type (Phthalocyaninato)(porphryinato) Europium Triple-decker Nanotubes. Effect of the Substituents on the Molecular PackingA series of three sandwich-type (phthalocyaninato)(porphyrinato) europium triple-decker complexes, namely Eu2(Pc)2(TClPP) (1), Eu2[Pc(β-OC4H9)8]2(TClPP) (2), and Eu2[Pc(β-OC8H17)8]2(TClPP) (3), were fabricated into nanotubes using nanoporous anodized aluminum oxide (AAO) membrane as the template. The tubular structure was studied by various spectroscopic, electronic microscopic, and X-ray diffraction techniques. The outer diameter of the nanotubes was revealed to match very well with the pore diameter of AAO membrane, while the wall thickness of the nanotubes changes depending on the immersing time. The effect ofβ-substituents at the two phthalocyanine ligands in the triple-decker molecule on the molecular packing in the nanotubes along the alumina surface was clarified:Depending mainly on the intermolecularπ-πinteraction, the discotic molecules of 1 form columnar structures on the alumina surface with homeotropic (edge-on) stacking. In good contrast, introduction of eight alkyoxyl substituents at theβ-positions of the phthalocyanine ligands of 2 and 3 induces an increase in the interaction of the triple-decker molecules with the alumina surface, resulting in the formation of nanotubes with discotic molecules 2 and 3 parallel (face-on) stacking along the alumina surface.

  • 【网络出版投稿人】 山东大学
  • 【网络出版年期】2011年 12期
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