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1.
近年来,在配位化学领域,功能配位聚合物的设计与合成受到了越来越多的关注.配位聚合物以其精彩的结构和独特的性能有望成为重要的化学材料而具有潜在应用前景.含有杂环类的羧酸类配体已被广泛用于配位聚合物的合成,这类配体同时含有N原子和O原子作为配位原子,以其作为桥联配体与金属离子配位可以产生多种配位模式,从而形成结构丰富的金属配合物并展示多样的潜在性能.本文报道含有苯并咪唑羧基配体与甲酸混合配体与Mn(Ⅱ)和Co(Ⅱ)的两个新型配位聚合物的合成、结构与磁性.这两个配合物(1和2)通过溶剂热方法合成,它们是同构的具有3,6-连接拓扑的新型配合物,其Schlafli符号为{42;6}2{47;66;82}.磁性研究表明,化合物1具有自旋倾斜的反铁磁性行为,而化合物2仅具有简单的反铁磁性.  相似文献   

2.
吡啶-2,6-二甲酸配位聚合物的研究进展   总被引:1,自引:0,他引:1  
赵峰  李纲  李子峰  侯红卫 《化学研究》2006,17(3):108-112
概述了以吡啶-2,6-二甲酸为配体的配位聚合物的研究进展.按照同多核和异多核配位聚合物进行分类,并介绍了它们的合成技巧、结构特点以及突出性能等.  相似文献   

3.
通过使用不同尺寸的辅配体,我们合成了一系列以二价镍为金属离子,蒽醌四羧酸为主配体的金属有机框架化合物(1~5)。根据微相分离理论,通过选用不同尺寸的辅配体来调节聚合物的疏水体积比,我们得到具有不同结构的一系列配位聚合物。实验结果表明,化合物1和2表现为简单的二维层状结构,化合物3和4具有准三维结构,化合物5则具有三重穿插的二维结构。实验结果与微相分离理论所预测的结果相吻合。  相似文献   

4.
通过使用不同尺寸的辅配体,我们合成了一系列以二价镍为金属离子,蒽醌四羧酸为主配体的金属有机框架化合物(1~5)。根据微相分离理论,通过选用不同尺寸的辅配体来调节聚合物的疏水体积比,我们得到具有不同结构的一系列配位聚合物。实验结果表明,化合物1和2表现为简单的二维层状结构,化合物3和4具有准三维结构,化合物5则具有三重穿插的二维结构。实验结果与微相分离理论所预测的结果相吻合。  相似文献   

5.
在过去的二十多年里,多孔配位聚合物(PCPs,又称金属-有机框架化合物,MOFs)由于具有丰富的结构特点和潜在的应用功能而受到人们的广泛关注.本文主要综述了基于三个平面刚性配体咪唑-4,5-二甲酸(H3IDC)、1H-四氮唑(HTz)和1H-四氮唑-5-甲酸(H2Tzc)的多孔配位聚合物的研究进展,包括配位聚合物的合成、晶体结构和性能研究.  相似文献   

6.
在溶剂热条件下合成了2个锌(Ⅱ)/镉(Ⅱ)配位聚合物:{[Zn(1,3-bip)(bpdc)]·0.5H2bpdc}n(1),{[Cd2(1,3-bip)2(bpdc)2]·DMF}n(2),H2bpdc=4,4′-联苯二甲酸,1,3-Bip=1,3-二(咪唑基)丙烷。并通过X射线单晶衍射,粉末XRD、红外光谱、元素分析以及热重分析对其结构进行表征。单晶解析结果表明:配位聚合物1是一个五重穿插3D→3D三维空间网络结构,配位聚合物2是一个二重穿插的2D→2D二维的(4,4)网格层状结构。另外,研究了2个配位聚合物在室温下的热稳定和荧光性能。  相似文献   

7.
金属-有机框架多孔化合物(MOF)由于其微孔结构的可设计性、可调节性和优越的吸附性能,近年来被广泛用于气体分离、储存、催化、药物传输等方面的研究.以往的研究主要集中在通过改变金属中心离子和功能化的配体,进而合成大量的MOF化合物并研究它们在H2,N2,CH4,CO2等气体吸附和分离方面的行为.然而通过合成一些具有开放金属位点的MOF,从而达到改变其吸附性能,或者通过MOF的后修饰改善其催化性能等方面的工作,则相对较少.本论文利用一个"T型"的配体,5-异烟酸酰胺间苯二甲酸(5-(isonicotinamido)isophthalicacid(H2INAIP)),与Zn(NO3)2.6H2O在溶剂热的条件下反应得到了一个二重穿插的三维配位多孔聚合物{[Zn(INAIP)(DMF)].0.5DMF.4H2O}n(1).晶体结构分析表明,这个Zn-MOF的中心离子配位数为5,而且具有一维的通道,配位的溶剂分子DMF伸向通道内侧.热重和变温粉末实验表明,除去溶剂分子后,活化的多孔化合物可以提供一些开放的金属位点,同时化合物骨架保持了较高的稳定性.气体吸附试验表明化合物1可以吸附N2,表现出Ⅰ型吸附脱附行为.  相似文献   

8.
配位聚合物由于其在分子识别、催化、光电性质和磁性等方面表现出的独特性能.近年来已引起人们的极大关注。含氮、含氧桥联配体是合成具有不同拓扑结构的配位聚合物的重要原料。而氢键的存在,往往使配合物单分子之间相互连结。形成具有一维、二维或三维网络结构和多维结构的分子聚集体,从而降低了分子体系能量,稳定了体系结构,其结果可能赋予这些化合物某些新的(如光、  相似文献   

9.
李启彭  罗家刚  和晓全  张泽俊 《化学通报》2016,79(11):1021-1027
手性配位聚合物因其结构多样性、可调控性以及潜在的多功能性,已经成为当前化学和材料学的研究热点。在合成中,可以通过选择特定的非手性配体、手性配体、手性溶剂或手性模板剂等来构筑手性配位聚合物。此外,还可以选择特定的金属离子赋予目标手性配位聚合物光、电、磁、催化和非线性光学等性能。本文详细综述了近年来纯手性配位聚合物的合成方法,以及在手性分离、手性催化、非线性光学、铁电和多铁等领域的应用研究进展。最后,对手性配位聚合物的合成方法及应用前景进行了展望。  相似文献   

10.
微孔配位聚合物作为新型储氢材料的研究   总被引:6,自引:0,他引:6  
杨勇  沈泓滢  邢航  潘毅  白俊峰 《化学进展》2006,18(5):648-656
微孔配位聚合物性质独特、结构多样,具有广泛的应用前景,它已成为近几年来一个热门的研究领域。本文简要介绍该类化合物作为一种新型的储氢材料,在合成、结构和储氢性能方面的研究进展。  相似文献   

11.
There are two categories of coordination polymers (CPs): inorganic CPs (i‐CPs) and organic ligand bridged CPs (o‐CPs). Based on the successful crystal engineering of CPs, we here propose noncrystalline states and functionalities as a new research direction for CPs. Control over the liquid or glassy states in materials is essential to obtain specific properties and functions. Several studies suggest the feasibility of obtaining liquid/glassy states in o‐CPs by design principles. The combination of metal ions and organic bridging ligands, together with the liquid/glass phase transformation, offer the possibility to transform o‐CPs into ionic liquids and other ionic soft materials. Synchrotron measurements and computational approaches contribute to elucidating the structures and dynamics of the liquid/glassy states of o‐CPs. This offers the opportunity to tune the porosity, conductivity, transparency, and other material properties. The unique energy landscape of liquid/glass o‐CPs offers opportunities for properties and functions that are complementary to those of the crystalline state.  相似文献   

12.
Exploring the charge transport properties and electronic functions of molecules is of primary interest in the area of molecular electronics. Conjugated polymers (CPs) represent an attractive class of molecular candidates, benefiting from their outstanding optoelectronic properties. However, they have been less studied compared with the small-molecule family, mainly due to the difficulties in incorporating CPs into molecular junctions. In this review, we present a summary on how to fabricate CP-based singlechain and monolayered junctions, then discuss the transport behaviors of CPs in different junction architectures and finally introduce the potential applications of CPs in molecular-scale electronic devices. Although the research on CP-based molecular electronics is still at the initial stage, it is widely accepted that (1) CP chains are able to mediate long-range charge transport if their molecular electronic structures are properly designed, which makes them potential molecular wires, and (2) the intrinsic optoelectronic properties of CPs and the possibility of incorporating desirable functionalities by synthetic strategies imply the potential of employing tailor-made polymeric components as alternatives to small molecules for future molecular-scale electronics.  相似文献   

13.
Chirality is an important concept in chemistry revealing intriguing optical properties such as circular dichroism (CD), circularly polarized luminescence (CPL), etc. As one of the non-centrosymmetric (NCS) classes, chiral materials with extended structures may exhibit unique nonlinear optical (NLO) properties, such as second-harmonic generation (SHG). In this Concept article, a series of recently discovered NCS coordination polymers (CPs) from use of carefully designed chiral organic ligands are reviewed. Combining several metal cations such as lanthanides, lead, zinc, and cadmium with rigid chiral ligands has resulted in interesting CPs with both polar and nonpolar structures. Detailed structures, SHG properties, and structure-property relationships are provided. The importance of hyperpolarizability formed by intermolecular hydrogen boding interactions to SHG is emphasized.  相似文献   

14.
π-Conjugated polymers(CPs)represent one of the quite important and rapidly growing branches of flexible electrochromic materials.Electrosynthesized hybrid CPs employing dibenzo pentacycles(fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran)as the backbones have received considerable attention owing to their special structures and interesting electrochromic performances.Recent studies show that polymers from these structures exhibit decent contrast ratios,favorable coloration efficiencies,low switching voltages,fast response time,excellent stability,and color persistence.Intrinsically,their electrochromic properties significantly depend on fine-tailoring of precursor monomer structures,and polymerization techniques and conditions.This review devotes to showing a clear picture of the research progress of dibenzo pentacycle-centered CPs via electrochemical polymerization,including fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran-based hybrid electrochromic polymers.Critical influences of the tailored precursor structures on their electropolymerization and resultant polymer performances are highlighted,aiming at providing an insight for the development of novel fused ring-based polymer electrochromic materials.  相似文献   

15.
Phthalocyanines are one of the important candidates of tetrapyrrolic macrocycles having a π-conjugated system, and conductive polymers (CPs) have recently attracted an increasing interest as designing of new molecular materials. A smart combination of these two unique structures can produce materials with the desired properties to design various organic-molecular devices. However, fundamental principles of the design engineering for synthesis of phthalocyanine-cored CP with unique optoelectronic properties has not been investigated yet. For this purpose, tetrasubstituted peripheral or non-peripheral Zn(II)-phthalocyanine containing thioalkyl- or alkoxy-group–linked carbazoles have been synthesized. Electropolymerization of the materials under potentiodynamic conditions yielded a series of analogous donor?acceptor CPs in which the only difference was the nature of the chalcogen (O or S) and substitution pattern (peripheral or non-peripheral) on the phthalocyanine core. This was shown to have a significant impact on the optical and electrochemical properties of the CPs because of the difference in electronegativity of chalcogen and inductive effect of the substitution pattern. Here, a comprehensive investigation of the design of phthalocyanine-cored CP has been concluded to reveal structure–property relationship.  相似文献   

16.
π-Conjugated polymers (CPs) and oligomers (COs) bearing hexaphenylbenzene (HPB) and tetraphenyl ethene (TPE) units were synthesized by Sonogashira and Suzuki–Miyaura coupling reactions. The optical properties of the CPs and COs were investigated by UV–vis, photoluminescence (PL), and fluorescence lifetime (τ) measurements. The PL intensities of the solutions of the CPs and COs synthesized by Sonogashira coupling were reduced upon addition of poor solvent like water, which is attributed to aggregation-caused quenching. In contrast, the CP and COs bearing the TPE unit synthesized by Suzuki–Miyaura coupling exhibited aggregation-induced emission enhancement in solution. This difference in fluorescence behavior is discussed herein in terms of the molecular sizes, conformations in solution, and τ values of the CPs and COs.  相似文献   

17.
Ko YJ  Mendez E  Moon JH 《Macromolecules》2011,44(13):5527-5530
Understanding and controlling aggregation structures of conjugated polymers (CPs) in aqueous solutions is critical to improving the physical and photophysical properties of CPs for biological applications. Here, we present spectroscopic evidence, including nuclear magnetic resonance (NMR) spectroscopic results, that different organic acid treatment induces different aggregation structures and photophysical properties of CPs in water. Conjugated polymer nanoparticles (CPNs) were fabricated by treating a non-aqueous soluble, primary amine-containing poly(phenylene ethynylene) (PPE-NH(2)) with organic acids followed by dialysis. CPNs formed by acetic acid (AA) treatment (CPN-AAs) exhibit characteristics of loose aggregation with minimal π-π stacking, while CPNs formed by tartaric acid (TA) treatment (CPN-TAs) exhibit a high degree of π-π stacking among PPE-NH(2) chains. The controlled aggregation for a specific application was demonstrated by comparing the fluorescence quenching abilities of the CPN-AAs and the CPN-TAs. A doubled Stern-Volmer constant was obtained from the densely packed CPN-TAs compared to that of the loosely aggregated CPN-AAs.  相似文献   

18.
The last two decades have witnessed the research activities in the area of coordination polymers (CPs), which are structurally diverse and functionally intriguing materials. In this endeavor, the most exploited ligand has been a structurally rigid N-donor compound having an innocent backbone (incapable of forming hydrogen bond) namely 4,4'-bipyridine. Much has been achieved by exploiting this wonder ligand in the area of CPs. However, the positional isomers such as 3,3'-bipyridine or 4,3'-bipyridine (which understandably induce diverse ligating topology as compared to their more symmetrical 4,4' counterpart) were not exploited in much detail presumably because of the difficulty in their synthetic accessibility. To get access to such N-donor ditopic ligands having diverse ligating topology, much efforts have been focused in the last decade or so to design such positional isomers of 4,4'-bipyridine having a non-innocent backbone (capable of forming hydrogen bond). The principal focus of such studies is to decipher the effect of diverse ligating topology and the non-innocent backbone of the ligands on the overall supramolecular structures and functions of the resultant CPs. This tutorial review aims at highlighting some of the developments of such structurally diverse and functionally intriguing CPs derived from N-donor ditopic ligands having a non-innocent backbone.  相似文献   

19.
The interest in two-dimensional conjugated polymers (2D CPs) has increased significantly in recent years. In particular, vinylene-linked 2D CPs with fully in-plane sp2-carbon-conjugated structures, high thermal and chemical stability, have become the focus of attention. Although the Horner-Wadsworth-Emmons (HWE) reaction has been recently demonstrated in synthesizing vinylene-linked 2D CPs, it remains largely unexplored due to the challenge in synthesis. In this work, we reveal the control of crystallinity of 2D CPs during the solvothermal synthesis of 2D-poly(phenylene-quinoxaline-vinylene)s (2D-PPQVs) and 2D-poly(phenylene-vinylene)s through the HWE polycondensation. The employment of fluorinated phosphonates and rigid aldehyde building blocks is demonstrated as crucial factors in enhancing the crystallinity of the obtained 2D CPs. Density functional theory (DFT) calculations reveal the critical role of the fluorinated phosphonate in enhancing the reversibility of the (semi)reversible C−C single bond formation.  相似文献   

20.
Conjugated polymers (CPs) have long been recognized as an important class of materials. The highly conjugated backbone of the CPs will facilitate the rapid exciton migration and result in amplification of fluorescence signals. However, CPs are likely to aggregate and form excimers in solid states, directly leading to the fluorescence quenching, namely aggregation-caused quenching (ACQ), hence inhibiting their prospective utilizations in a large degree. Since the effect of aggregation-induced emission (AIE) is opposite to that of notorious ACQ, the AIE has raised great attention from scientists. CPs with AIE or aggregation-enhanced emission (AEE) features may help to solve the ACQ problem and meanwhile impart polymers with new properties and practical applications. In this review, we summarize the recent progress on the preparation of CPs with AIE or AEE characteristics, where AIE-active luminogens are located at polymer backbones or pendants. Their potential applications including fluorescent sensors, biological probes, and active layers for the fabrication of light-emitting diodes are also described.  相似文献   

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