新荧光试剂5-(4'-卤代-2'-羧基苯偶氮)绕丹宁的合成及分析化学特性研究

合成了三种新荧光试剂,5-(4'-氯-2'-羧基苯偶氮)绕丹宁(CRACP.2).5-(4'-溴-2'-羧基苯偶氮)绕丹宁(BRACP,3)及5-(4'-碘-2'-羧基苯偶氮)绕丹宁(IRACP,4).研究了它们的吸收光谱及荧光性质.探讨了分子结构与荧光性能的关系.建立了铜(Ⅱ)的荧光分析方法.在pH5.3时.CRACP与铜( Ⅱ) 形成荧光螯合物, λ~ e~ x/ λ~e~m=310nm/408nm.检测限为5×10^-^4μg/g.     

新型树枝状分子3,5-二[3,5-二(4-羧基苯甲氧基)苯甲氧基]苯甲醇的合成

采用收敛法,以对氰基苄溴和3,5-二羟基苯甲醇为原料,依次合成了端基为腈基的芳醚树枝状分子3,5-二(4-腈基苯甲氧基)苯甲醇(4)和3,5-二[3,5-二(4-腈基苯甲氧基)苯甲氧基]苯甲醇(6);4与6分别经水解制得以羧基为端基的新型芳基苄醚树枝状分子3,5-二(4-羧基苯甲氧基)苯甲醇和3,5-二[3,5-二(4-羧基苯甲氧基)苯甲氧基]苯甲醇,其结构经UV-Vis,1H NMR,IR,MS和元素分析表征.     

2-硝基-4-氯-2'-羟基-3'-特丁基- 5'-甲基偶氮苯的固相合成

2-硝基-4-氯-2'-羟基-3'-特丁基- 5'-甲基偶氮苯的固相合成;硝基氯羟基特丁基甲基偶氮苯;固相合成;重氮偶合     

两种偶氮苯冠醚的合成及其光致变色机理

报道了4-氮杂15-冠-5-4'-甲氧基偶氮苯和4-氮杂15-冠-5-4'-硝基偶氮苯的合成及其分子内扭曲电荷转移的光致变色机理.     

新型磺化聚苯并咪唑的合成及性能

以对苯二酚及对氟苯甲腈为原料, 合成了1,4-二(4-羧基苯氧基)苯, 再经磺化反应合成了1,4-二(4-羧基苯氧基)苯-2-磺酸钠(BCPOBS-Na), 并以4,4'-二羧基二苯醚(DCDPE)作为非磺化二酸单体与3,3'-二氨基联苯胺反应合成了一系列磺化聚苯并咪唑(SPBI). 通过红外光谱、 核磁共振及热重分析等手段对聚合物的结构及性能进行了分析. 研究了聚合物的特性黏度、 溶解性、 成膜性及聚合物薄膜的力学性能.     

苯并噻唑偶氮吡唑和苯并噻唑偶氮嘧啶的合成

2-氨基苯并噻唑重氮盐与丙二腈偶联, 生成2-(苯并噻唑腙基)-丙二腈, 然后分别与水合肼, 苯肼和硝酸胍反应, 形成相应的4'-(苯并噻唑-2-偶氮)-3',5'-二氨基吡唑, 4'-(苯并噻唑-2-偶氮)-3',5'-二氨基-2'-苯并吡唑和5'-(苯并噻唑-2-偶氮)-2',4',6'-三氨基嘧啶.     

含氧化偶氮苯介晶基元共聚醚的合成与液晶行为

以1,6-二溴己烷(A)和1,10-二溴癸烷(B)为共缩聚单体,按不同摩尔配比与4,4'-二羟基氧化偶氮苯经相转移催化共聚醚化反应,合成了一系列主链上含有氧化偶氮苯介晶基元的共聚醚,它们均有好的液晶性,其取向膜观察到条带织构,当A/B的摩尔比为1时液晶态范围最宽。     

水溶性双冠醚的合成

双冠醚与较大的金属离子能形成夹心型络合物,与相应的单冠醚相比较,它们具有更好的络合性和选择性。但双冠醚一般不溶于水中。本文用EDTA二酐与4'-氨基苯并-12-冠-4及4'-氨基苯并-15-冠-5反应,制得了两种在桥键上带有两个羧基的酰胺型双冠醚Ⅰ和Ⅱ。Ⅰ、Ⅱ未见报导,均能溶于水,这就可以象其它水溶性单冠醚一样,在水溶液中研究它们的络合行为。     

新试剂——氯膦羧偶氮Ⅲ

含膦羧基—PO_3H_2的有色有机试剂合成的还不多,除氯膦羧偶氮I~*(I)外,就是氯膦羧偶氮III(又名偶氮氯膦III)(III)。首先由和等人合成并用于铀的测定中。试剂名称为2,7-双-(4-氯-2-膦羧苯偶氮)-1,8-二羟基萘-3,6-二磺酸。其结构式为.     

冠醚侧链液晶聚硅氧烷配体及其钠配合物的研究

本文以二茂基二氯化铂为催化剂,使含液晶基元的单体4-(烯丙基氧)-4'-(4'-羧基苯并15-冠-5)-α,ω-二苯氧丁烷和聚甲基硅氧烷进行硅氢加成反应,合成了一种新的冠醚侧链液晶聚硅氧烷配体及其钠配合物。采用DSC和偏光显微镜方法研究了单体、配体和配合物的液晶行为,发现它们均具有热致液晶性。     

Synthesis and characterization of dendrons and dendrimers skeleton-constructed with azobenzene moiety

A series of dendrons and dendrimers skeleton-constructed with azobenzene moiety based upon 4-carboxy-4′-(1,2-propanediolether)-azobenzene as an AB₂ monomer, via a convergent approach, proceeding in a repeated stepwise growth manner starting from 4-carboxy-4′-(n-butylether)-azobenzene as a peripheral monomer, were synthesized, and characterized by NMR, FTIR, and MALDI-TOF-MS analysis. Their regular molecular architecture and thus monodispersed molecular weights were confirmed by GPC. The UV-Vis absorbance and ¹H NMR spectrum study indicated that the azobenzene moieties in CHCl₃ solution took fully trans-cis isomerization under UV irradiation, and reversely isomerization back to the trans by visible light irradiation or by heat.     

Solvent induced amplification of the photoresponsive properties of α,ω-di-[4-cyanophenyl-4'-(6-hexyloxy)-azobenzene]-poly(N-isopropylacrylamide) in aqueous media

Irradiation at room temperature of α,ω-di-[4-cyanophenyl-4'-(6-hexyloxy)-azobenzene]-poly-(N-isopropylacrylamide) (Az(2)-PNIPAM) solutions in water/1,4-dioxane (6 mol% dioxane) reversibly converts a turbid suspension into a clear solution, demonstrating for the first time that cononsolvency of PNIPAM in mixed aqueous solvents in synergy with preferential chromophore solvation can act as actuators of responsive systems.     

Voltammetric behavior of poly(amidoamine) dendrimers containing nitroxyl radical end groups

A series of fully functionalized poly(amidoamine) dendrimers with 4-carboxy-2,2,6,6-tetramethylpiperidin-1-yloxyl end groups were prepared. Cyclic voltammetric studies indicated that the pendant nitroxyl radical end groups are non-interacting electrochemically equivalent redox centers, which are oxidizable at the same potential. The results of controlled-potential electrolysis of the dendrimers showed that all the nitroxyl radical groups at the periphery of the dendrimers are accessible to the electrode surface for electron transfer.     

Liquid crystalline side group polymers with azo-chromophores and fluorinated tails of varying length

A series of side group liquid crystalline polymethacrylates with 4'-(1H,1H-perfluoroalkoxy)-azobenzene mesogenic units was synthesized and characterized by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction methods depending on the tail length. The phase behaviour is discussed as a function of the length of the tail groups. Very high clearing temperatures up to 290°C were observed for the polymers with long tail groups.     

Dendronized Hyperbranched Macromolecules: Soft Matter with a Novel Type of Segmental Distribution

Dendronization of a hyperbranched polyester with different generation dendrons leads to pseudo‐dendritic structures. The hyperbranched core is modified by the divergent coupling of protected monomer units to the functional groups. Compared to dendrimers, the synthetic effort is significantly less, but the properties are very close to those of high‐generation dendrimers. The number of functional groups, molar mass, and rheology behavior even in the early generation (G1–G4) pseudo‐dendrimers strongly resembles the behavior of dendrimers in higher generations (G5–G8). Comparison of the segmental and internal structure with perfect dendrimers is performed using SANS, dynamic light scattering and viscosity analysis, microscopy and molecular dynamics simulation. The interpretation of the results reveals unique structural characteristics arising from lower segmental density of the core, which turns into a soft nano‐sphere with a smooth surface even in the first generation.     

Synthesis, chiroptical properties and photoinduced linear birefringence of the homopolymer of (R)-3-methacryloyloxy-1-(4′-cyano-4-azobenzene)pyrrolidine and of the copolymers with the enantiomeric monomer

We have investigated a new optically active photochromic homopolymer poly[(R)-3-methacryloyloxy-1-(4′-cyano-4-azobenzene)pyrrolidine] containing in the side-chain a chiral group of one prevailing configuration linked to a trans-azoaromatic system. As expected it exhibits in solution homogeneous conformations with a prevailing chirality induced by dipole-dipole interactions between side-chain chromophores. Copolymers with the enantiomeric monomer (S)-3-methacryloyloxy-1-(4′-cyano-4-azobenzene)pyrrolidine have also been prepared in order to evaluate the effect on the photoinduced optical properties of side-chain chiral groups of opposite configuration in various ratios. The possibility of producing reversible photomodulation of linear birefringence without any significant degradation of these materials seems to be promising for their use in optical data storage.     

Comparison of AB2 and AB4 monomers in ferrocene-cored benzyl ether dendrimers

Ferrocene-cored unsymmetric and symmetric arylalkyl ether dendrimers based on an AB₂ monomer (3,5-dihydroxybenzyl alcohol) were prepared. Their electrochemical properties were compared with the unsymmetric and symmetric ferrocene-cored dendrimers based on a relatively rigid and three-dimensionally disposed AB₄ monomer. The thermodynamics and kinetics of heterogeneous electron transfer in these dendrimers show that G_2n of AB₂ dendrimers behave similar to G_n of AB₄ dendrimers. For example, the redox reaction shows significant irreversibility especially at higher scan rates in the case of G₄ didendron based on AB₂ monomer and G₂ didendron based on AB₄ monomer. Despite the fact that AB₄ building blocks are more rigid, the effective encapsulation in both these dendrimers are similar. This result is attributed to the three dimensional disposition of the branching points in the AB₄ monomer.     

银岛膜中银颗粒间表面电磁波的耦合

自从Hartstcil。等人用衰减全反射技术（AT则得到覆盖在银岛膜上的有机超薄膜的表面增强红外吸收光谱以来山，对其增强机理及应用的研究一直是人们关注的热点．人们不论是从实验上还是从理论上都通过种种努力来探索表面增强红外光谱的机理，但仍然没有给出一个清晰的图象．一般     

Poly(propylene imine) dendrimers as hydrogen donor in Type II photoinitiated free radical polymerization

Three generations of poly(propylene imine) dendrimers, namely (PPI-16, PPI-32 and PPI-64; 16, 32 and 64 for generations 3, 4 and 5, respectively) were used as hydrogen donors in photoinitiated free radical polymerization of methyl methacrylate by using one of the following photosensitizers; benzophenone and thioxanthone. The effect of generation number of the dendrimer on photoinitiation efficiency and molecular weight of the resulting polymers was investigated. Glass transition temperatures and particle size measurements of the resulting polymers indicated the presence of nearly stretched polymer chains around the dendrimers. The location of hydrogen donating sites was evaluated by photolysis studies in the absence of monomer by using a stable radical namely, 2,2,6,6-tetramethylpiperidine-N-oxyl free radical (TEMPO) and showed that hydrogen abstraction occurs from the inner tertiary amino groups. The TEMPO attached dendrimers were further used in the nitroxide mediated radical polymerization (NMP) of styrene to yield star polymers.     

Optically Active Methacrylic Polymers Bearing in the Side Chain the (S)-3-Hydroxypyrrolidinyl Group Linked to trans-bisazoaromatic Chromophore: Synthesis and Characterization

The synthesis by radical homopolymerization of a novel optically active methacrylic polymer containing a side-chain chiral moiety linked to a photochromic bisazoaromatic chromophore has been carried out starting from the related monomer (S)-3-methacryloyloxy-1-[4′-phenylazo-(4-azobenzene)]-pyrrolidine [(S)- MPAAP ]. The polymeric derivate has been fully characterized and its spectroscopic properties compared to those of the monomer and of the corresponding homopolymer bearing only one azoaromatic chromophore in the side chain. The optical activity displayed by the bisazo polymer is discussed in terms of extent of chiral conformation assumed by the macromolecules as a consequence of dipole-dipole interactions between the bisazoaromatic chromophores.