Design,synthesis, and optical/electronic properties of a series of sphere-rod shape amphiphiles based on the C<Subscript>60</Subscript>-oligofluorene conjugates

A series of sphere-rod shape amphiphiles were designed and synthesized by connecting the rod-like oligofluorenes with different lengths (OF _n ) to the different positions of the spherical [60]fullerene (C₆₀) through a rigid linkage. The conjugates were characterized by ¹H-NMR, ¹³C-NMR, FTIR, EA and MALDI-TOF mass spectrometry. The optical and electronic properties of the conjugates were studied by UV-Vis absorption spectroscopy, fluorescence spectrometry, and cyclic voltammetry. The results from UV-Vis absorption spectroscopy and cyclic voltammetry indicated that the energy profiles of C₆₀ and OF _n remained unchanged when different lengths of OF _n were attached to C₆₀. The electron affinities of the OF _n -C₆₀ conjugates were close to that of C₆₀, while slight electronic interaction was found between the two individual chromophores (C₆₀ and OF _n ) in their ground states. The fluorescence spectra exhibited a complete fluorescence quenching in the toluene solution, suggesting an effective energy transfer from OF _n to C₆₀. It presents a systematic study on the self-assembly, structure-property relationship, and potential technical applications of the conjugates.     

1,8-萘酰亚胺衍生物的合成、表征及电存储性能

本文以三苯胺结构作为电子给体,与三种接有不同吸电子基团的1,8-萘酐反应合成了具有电子给-受体结构的N-(4-三苯胺)-1,8-萘酰亚胺(NA-ATPA)、N-(4-三苯胺)-(4-氰基)-1,8-萘酰亚胺(NA(CN)-ATPA)和N-(4-三苯胺)-(4-硝基)-1,8-萘酰亚胺(NA(NO_2)-ATPA),并对它们的结构进行了表征。利用紫外可见光谱、荧光发射光谱和循环伏安法对产物的光物理性能和电化学性能进行了测试,并测试了其存储行为,结果显示NA-ATPA表现出易失的静态随机存储行为(SRAM),NACN-ATPA表现出非易失的闪存型存储(Flash),NA(NO_2)-ATPA表现出非易失只读型存储(WORM)。三种萘酰亚胺对存储行为中高导态的维持能力逐渐增强,其原因是引入的吸电子基团的吸电子性越强,其LUMO值和能隙值降低的越多,越利于电荷转移,形成更稳定的电荷转移络合物。另外,本文还对原料和产物的电子结构、分子轨道和能级进行了分子模拟计算,研究了三种化合物基态和激发态的差别,并对其电子转移过程进行了理论分析。     

Preparation and the investigation of its electrochemical and photoluminescent characteristics of organic-inorganic hybrid multilayers containing europium-substituted heteropolytungstate

Photoluminescent multilayers were fabricated by layer-by-layer deposition between europium-substituted heteropolytungstate K₁₃[Eu(SiW₁₁O₃₉)₂]·28H₂O (denoted ESW) and a cationic polymer of quaternized poly(4-vinylpyridine) partially complexed with osmium bis(2,2′-bipyridine) (denoted as QPVP-Os) on glassy carbon and quartz substrates. The resulting photoluminescent organic-inorganic hybrid multilayers were characterized by electrochemical impedance spectroscopy, UV-Vis absorption spectrometry, cyclic voltammetry and photoluminescence spectra. Electrochemical impedance spectroscopy, UV-Vis absorption spectrometry and cyclic voltammetry results demonstrated that the multilayers were regular growth each layer adsorption. The photoluminescent properties of the films at room temperature were investigated to show the characteristic Eu³⁺ emission pattern of ⁵D₀→⁷F_j.     

Synthesis and Characterization of a Noncovalently Linked Porphyrin-[1,2-(1-acridin-10′-yl-2-aza-2-methylprop-1,3-ylene)-fullerene]Dyad

1,2-(1-Acridin-10'-y1-2-aza-2-methylprop-1,3-ylene)fullerene was synthesized firstly and characterized byUV-Vis,~1H NMR,~(13)C NMR and electrospray ionization mass spectroscopy,which is capable of forming a stablecomplex with zinc tetraphenylporphyrin via the axial ligafion.The steady state fluorescence studies show efficientquenching of the zinc tetraphenylporphyrin emission upon axial coordination of acridine attached to C_(60).     

两种钒配合物的合成、表征及与Ct-DNA作用研究

合成了两种钒-邻香草醛衍生物配合物[VO2(C10H11O3N)](HOCH2CH2NH3) (1)和VO(C8H8O3N)2 (2); 用FT-IR和X-ray单晶衍射对它们的晶体结构进行了表征; 用紫外吸收光谱法、荧光光谱法、循环伏安法、粘度法等分析了两种配合物与小牛胸腺DNA (Ct-DNA)的作用; 结果表明配合物1以非插入方式与Ct-DNA作用, 配合物2则以插入方式与Ct-DNA作用.     

四(对己氧苯基)卟啉稀土配合物的合成,表征和电化学性质

合成了四种乙酰丙酮-meso-四(对己氧苯基)卟啉稀土配合物,LnT(p-C6H13O)PPacac(Ln:Y,Dy,Er,Yb;Hacac:乙酰丙酮),研究了其紫外-可见光谱、红外光谱、氢核磁共振谱和荧光光谱,对各个谱带进行了归属,并用循环伏安法对其电化学性质进行了研究.     

Synthesis and characterization of 5,10,15,20-tetra[3-(3-trifluoromethyl)phenoxy] porphyrin

The newly synthesized 5,10,15,20-tetra[3-(3-trifluoromethyl)phenoxy]porphyrin, TTFMPP, has been characterized using mass spectroscopy, 1H-, 13C- and 19F-NMR, MALDI-TOF mass spectrometry, UV-Vis and fluorescence spectrophotometry, and cyclic voltammetry. The NMR confirmed the structure of the compound and the mass spectrum was in agreement with the proposed molecular formula. The UV-Vis absorption spectrum of TTFMPP shows characteristic spectral patterns similar to those of tetraphenyl porphryin, with a Soret band at 419 nm and four Q bands at 515, 550, 590, and 648 nm. Protonation of the porphyrin with TFA resulted in the expected red shift of the Soret band. Excitation at 419 nm gave an emission at 650 nm. The quantum yield of the porphyrin was determined to be 0.08. Cyclic voltammetry was used to determine the oxidation and reduction potentials of the new porphyrin. Two quasi-reversible one-electron reductions at -1.00 and -1.32 V and a quasi-reversible oxidation at 1.20 V versus the silver/silver chloride reference electrode with tetrabutylammonium tetrafluoroborate as the supporting electrolyte in methylene chloride were observed.     

Activating multistep charge-transfer processes in fullerene-subphthalocyanine-ferrocene molecular hybrids as a function of π-π orbital overlap

We have synthesized two different fullerene-subphthalocyanine-ferrocene conjugates. The molecules were designed so that the ferrocene unit is linked at the subphthalocyanine axial position through a phenoxy spacer while the C(60) is rigidly held close to the concave face of the macrocycle via a 3-fold C(3)-symmetrical anchoring. The Bingel trisaddition reaction leading to the final products proceeded with very high regioselectivities and full diastereoselectivity. The only difference between both systems is the length of the triple tether employed, which finely regulates the regioselectivity of the trisaddition reaction and the distance between the subphthalocyanine and the C(60) complementary π-π surfaces. Thus, when the tether is connected to the subphthalocyanine through a direct C-C bond, a short π-π distance of 3.25-3.30 ? was calculated. In contrast, when it is connected through a slightly longer C-O-C bond, the distance increases to 3.5-3.6 ?. This π-π distance has a strong influence on the ground-state electronic interactions between the subphthalocyanine and the C(60), as determined from electronic absorption and cyclic voltammetry measurements. In addition, fluorescence and time-resolved transient absorption experiments demonstrated that different mechanisms operate in the two systems after photoexcitation. Despite the similar HOMO-LUMO gaps, only when the two complementary π-π surfaces of the subphthalocyanine and the C(60) are held at a close distance, therefore showing a high degree of orbital overlap, is a multistep electron transfer process triggered, ultimately leading to the long-lived, spatially separated C(60) radical anion and ferrocenium radical cation pair. A full account of the synthesis, characterization, and studies of the ground- and excited-state electronic interactions occurring in these conjugates, as well as in their reference C(60)-subphthalocyanine and subphthalocyanine-ferrocene dyads, is presented in this article.     

异咯嗪修饰富勒烯-聚丙烯酸的合成及其与DNA的相互作用

利用自由基聚合反应合成了聚丙烯酸修饰的富勒烯(C₆₀-PAA),进一步通过酯化反应将核黄素类似物6,7-二甲基-9-(2’-羟乙基)-异咯嗪(DHIX)与C₆₀-PAA共价连接,得到C₆₀-PAA-DHIX.利用傅立叶红外光谱(FT-IR)、核磁共振氢谱(¹HNMR)、紫外-可见吸收光谱(UV-Vis)、荧光光谱对产物的化学结构进行了表征.循环伏安法表明,C₆₀-PAA-DHIX中富勒烯基团的第一还原电位要高于DHIX基团的第一还原电位.ESR实验表明C₆₀-PAA-DHIX能与N,N-二甲基苯胺发生多步光诱导电子转移反应,即DHIX基团与N,N-二甲基苯胺发生光诱导电子转移生成DHIX负离子自由基(DHIX^-·),DHIX^-·能进一步将电子传递给富勒烯生成富勒烯负离子自由基.DNA熔解曲线、紫外-可见吸收光谱和荧光光谱结果表明,C₆₀-PAA-DHIX通过沟槽结合与CTDNA作用,而C₆₀-PAA与DNA的作用较弱.无氧条件下,C₆₀-PAA-DHIX具有比C₆₀-PAA更强的DNA光损伤能力.     

Cytotoxicity activity,in silico molecular docking,protein- and DNA-binding study of a new Ni(II) Schiff base complex

Abstract

One new nickel(II) complex, [Ni(L)] (1), was synthesized from the Schiff base ligand derived from pyrrole-2-carboxaldehyde and 1,3-diaminopropane. Complex 1 was characterized by elemental analysis, IR, UV-Vis and ESI mass spectroscopy, cyclic voltammetry, and single-crystal X-ray structure analysis. Crystallographic results show that two Ni(II) monomeric moieties are present with similar structural features but with slightly different bond lengths and bond angles. The geometry around the Ni(II) center is distorted square planar. DNA-binding properties of complex 1 were well explored by employing UV-Vis and fluorescence spectral methods, cyclic voltammetry, and by viscosity measurements. Similarly the protein-binding study was studied by multispectroscopic techniques using both BSA and HSA. The cytotoxicity study of the compound has also been evaluated. Notably, the in vitro cytotoxicity of complex 1 on two cancer cell lines (AGS and A549) demonstrates that complex 1 has very good anticancer activity. MTT assay, cell-cycle analysis, and annexin-V assay have been performed to know the extent of effect of complex 1 as anticancer agent. Further, in silico molecular docking study revealed that the nickel(II) complex fits into the minor groove of duplex DNA by hydrophobic interaction with functional groups of B-DNA.     

竹红菌甲素与血红蛋白相互作用光谱

竹红菌甲素与血红蛋白相互作用光谱;马心血红蛋白;竹红菌甲素;相互作用;UV-Vis吸收光谱;荧光光谱;荧光猝灭动力学常数     

Promising fast energy transfer system via an easy synthesis: Bodipy-porphyrin dyads connected via a cyanuric chloride bridge, their synthesis, and electrochemical and photophysical investigations

The boron dipyrrin (Bodipy) chromophore was combined with either a free-base or a Zn porphyrin moiety (H(2)P and ZnP respectively), via an easy synthesis involving a cyanuric chloride bridging unit, yielding dyads Bodipy-H(2)P (4) and Bodipy-ZnP (5). The photophysical properties of Bodipy-H(2)P (4) and Bodipy-ZnP (5) were investigated by UV-Vis absorption and emission spectroscopy, cyclic voltammetry, and femtosecond transient absorption spectroscopy. The comparison of the absorption spectra and cyclic voltammograms of dyads Bodipy-H(2)P (4) and Bodipy-ZnP (5) with those of their model compounds Bodipy, H(2)P, and ZnP shows that the spectroscopic and electrochemical properties of the constituent chromophores are essentially retained in the dyads indicating negligible interaction between them in the ground state. In addition, luminescence and transient absorption experiments show that excitation of the Bodipy unit in Bodipy-H(2)P (4) and Bodipy-ZnP (5) into its first singlet excited state results in rapid Bodipy to porphyrin energy transfer-k(4) = 2.9 × 10(10) s(-1) and k(5) = 2.2 × 10(10) s(-1) for Bodipy-H(2)P (4) and Bodipy-ZnP (5), respectively-generating the first porphyrin-based singlet excited state. The porphyrin-based singlet excited states give rise to fluorescence or undergo intersystem crossing to the corresponding triplet excited states. The title complexes could also be used as precursors for further substitution on the third chlorine atom on the cyanuric acid moiety.     

Photophysical and electrochemical properties of meso, meso-linked oligoporphyrin rods with appended fullerene terminals.

The electrochemical and photophysical properties of molecular architectures consisting of oligomeric meso,meso-linked oligoporphyrin rods linked at both extremities to methanofullerene moieties are presented in comparison to those of model systems. Cyclic voltammetry data evidence the presence of a strong intramolecular electronic coupling along the porphyrin oligomers that varies slightly with their length. This interaction affects the redox potentials of both fullerene and porphyrin moieties. The electronic coupling between the two chromophores is confirmed by comparing the redox potentials of porphyrin arrays before and after attachment of the carbon sphere. Electronic absorption, fluorescence, and phosphorescence spectra of the porphyrin oligomers in toluene are reported, which provide the energy of the lowest singlet and triplet electronic excited states. In the fullerene-porphyrin conjugates, ground-state charge-transfer (CT) interactions are evidenced by low-energy absorption features above 750 nm. These systems also exhibit near-infrared (NIR) CT luminescence in toluene with lifetimes shorter than 1000 ps. On increasing the solvent polarity (from toluene to Et2O and THF), CT emissions become progressively weaker, red-shifted, and shorter lived, which reflects the energy-gap law and Marcus inverted region effects. Luminescence is not detected in benzonitrile. Picosecond transient absorption spectroscopy of the porphyrin-fullerene conjugates allows detection of the porphyrin cation as a clear fingerprint for electron transfer. The rate of charge recombination is in agreement with CT luminescence lifetimes, which confirms the occurrence of NIR radiative back-electron transfer.     

含有偶氮苯和1,3,4-噁二唑结构聚合物的合成及性能

合成了同时含有偶氮苯和1,3,4-噁二唑结构的新型共轭聚合物(LPOXD),采用FT-IR、UV-Vis、1H NMR、GPC、TGA和DSC测试技术对其结构进行了表征。 结果表明,所得共轭聚合物的特性粘数为0.02960 L/g,Mw和分子量分布指数PDI分别为8500 g/mol和1.55。 质量损失5%的温度为290 ℃,Tg为92.8 ℃。 长烷氧基侧链的引入极大地提高了LPOXD在氯仿和四氢呋喃等有机溶剂中的溶解性。 采用紫外-可见吸收光谱、荧光光谱及循环伏安对LPOXD的光电性能进行了研究。 结果表明,在365 nm紫外光照射下,LPOXD中偶氮苯发生反-顺异构化;350 nm光激发下,LPOXD在蓝紫光波长范围内发射荧光;循环伏安测试得出LPOXD最高占有轨道(HOMO)能量和最低空轨道(LUMO)能量分别为-5.96和-3.17 eV。     

C80 encaging four different atoms: the synthesis, isolation, and characterizations of ScYErN@C80

The synthesis, isolation, and spectroscopic characterizations of an endohedral fullerene with four heteroatoms encapsulated (ScYErN@C80) are reported for the first time. The isomeric structure and electronic properties of this molecule are studied by various spectrometry methods such as high-performance liquid chromatography (HPLC), laser desorption time-of-flight (LD-TOF) mass spectroscopy, cyclic voltammetry, Fourier transform infrared (FTIR) spectroscopy, and visible-near infrared (vis-NIR) absorption spectroscopy. The carbon cage of ScYErN@C80 is assigned as Ih-C80, and the four-membered ScYErN cluster is suggested to rotate rapidly inside the fullerene cage. Six electrons are transferred from the nuclear cluster ScYErN to the fullerene cage, which leads to a closed-shell electronic structure of the Ih-C80 and results in excellent stability of this molecule.     

Aucore Ptshell纳米粒子对甲醇氧化的电催化性能研究

应用两步化学还原法制备不同厚度的AucorePtshell纳米粒子,经紫外可见光谱(UV-V is)、透射电子显微镜(TEM)表征.该金纳米颗粒经化学还原包裹铂后平均粒径明显增大,调节金与铂的含量可获得不同包裹厚度的AucorePtshell纳米粒子.循环伏安法研究表明,粒径为70~80 nm的AucorePtshell纳米粒子对甲醇的氧化具有较好的电催化活性,并且其电催化性能随着电位循环扫描次数的增加而增强.     

Salen型化合物的合成、表征及性质

设计合成了两种新型Salen配体H2L1(N,N?-3-二甲氧基-邻羟苯亚甲基-4,5-二甲氧基-1,2-苯二胺)、H2L2(N,N?-3-二甲氧基-邻羟苯亚甲基-4,5-二硝基-1,2-苯二胺)及相应的镍、铜、锌金属配合物ML1、ML2(M=Ni,Cu,Zn),并分别采用核磁共振(1HNMR)波谱、紫外-可见(UV-Vis)吸收光谱、红外(IR)光谱、质谱(MS)和元素分析进行了表征.探究了配体及其配合物的荧光性质.研究发现,与H2L1相比,配体H2L2由于引入强的吸电子基团―NO2,其荧光强度减弱.相对于配体,锌离子的配位则导致其配合物的荧光强度增强,而镍和铜离子的嵌入则使得配合物ML1、ML2(M=Ni,Cu)荧光猝灭.对电化学性质的研究表明,CuL1的氧化还原过程为准可逆的单电子过程;与H2L2相比,配体H2L1由于引入强的给电子基团―OCH3,其溶液的导电性降低.     

AucorePtshell础纳米粒子对甲醇氧化的电催化性能研究

应用两步化学还原法制备不同厚度的AucorePtshell纳米粒子，经紫外可见光谱（UV-Vis）、透射电子显微镜（TEM）表征．该金纳米颗粒经化学还原包裹铂后平均粒径明显增大，调节金与铂的含量可获得不同包裹厚度的AucorePtshell纳米粒子．循环伏安法研究表明，粒径为70-80nm的AucorePtshell纳米粒子对甲醇的氧化具有较好的电催化活性，并且其电催化性能随着电位循环扫描次数的增加而增强．     

利用聚合物自组装实现绿色荧光蛋白生色团的荧光增强

根据绿色荧光蛋白的发光原理,采用聚乙二醇与聚甲基丙烯酸甲酯的两亲性两嵌段聚合物通过自组装包覆生色团的方式,模拟了绿色荧光蛋白发光,考察了组装行为对光学性能的影响,并将其用于细胞成像.通过核磁共振、高分辨质谱、傅里叶变换红外光谱、凝胶渗透色谱、紫外-可见吸收光谱及荧光光谱等表征了生色团分子和聚合物的结构及性能.生色团紫外最大吸收在371 nm,荧光最大发射峰在428 nm.聚合物和生色团进行组装后,其紫外吸收消失,而最大荧光发射峰强度大大增强,且发生了约70 nm的红移,这是因为组装使得生色团的自由旋转受到了限制,且生色团共平面性增加.动态光散射(DLS)和透射电镜(TEM)证明了纳米粒子的结构和尺寸.由于尺寸适合且具有较好的荧光性能,纳米粒子成功应用于细胞成像.这种绿色荧光蛋白生色团的简单自组装方式在生物成像领域具有良好应用前景.     

Synthesis, characterization, and photoinduced electron transfer in functionalized single wall carbon nanohorns

Single-wall carbon nanohorns (SWNHs) are a new class of material that is closely related to single-wall carbon nanotubes. Here, we describe the synthesis and characterization of a series of SWNHs functionalized with ethylene glycol chains and porphyrins. Functionalization of carbon nanohorns has been achieved using two different synthetic protocols: (1) direct attack of a free amino group on the nanohorn sidewalls (nucleophilic addition) and (2) amidation reaction of the carboxylic functions in oxidized nanohorns. The nanohorn derivatives have been characterized by a combination of several techniques, and the electronic properties of the porphyrin/nanohorn assemblies (SWNH/H2P) have been investigated by electrochemistry, spectroelectrochemistry, and a series of steady-state and time-resolved spectroscopy. The cyclic voltammetry curve of nanohorn/porphyrin conjugate 6 showed a continuum of faradic and pseudocapacitive behavior, which is associated with multiple-electron transfers to and from the SWNHs. Superimposed on such a pseudocapacitive current, the curve also displays three discrete reduction peaks at -2.26, -2.57, and -2.84 V and an oxidation peak at 1.12 V (all attributed to the porphyrin moiety). Steady-state and time-resolved fluorescence demonstrated a quenching of the fluorescence of the porphyrin in SWNH/H2P conjugates 5 and 6 compared to the reference free base porphyrin. Transient absorption spectra permitted the electron-transfer process between the porphyrins and the carbon nanostructures to be highlighted.