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1.
水溶性卟啉催化氧化1,5-萘二酚   总被引:1,自引:0,他引:1  
合成并表征了系列水溶性卟啉配体[H2TPPS: 5,10,15,20-四-(4-磺酸基苯基)-21H,23H-卟啉, H2TMPyP: 5,10,15,20-四(4-吡啶基)-21H,23H-卟啉, H2TCPP: 5,10,15,20-四-(4-羧基苯基)-21H,23H-卟啉]及相应的铁、锌及钴配合物. 将水溶性卟啉作为光敏剂, 用于1,5-萘二酚的光催化反应, 产物为5-羟基-1,4萘醌. 利用UV-Vis方法对卟啉催化1,5-萘二酚的反应过程进行了监测, 探索了水相和水/二氯甲烷双相催化体系, 确定了较为理想的反应条件. 探讨了不同取代基和不同金属离子对卟啉催化性能的影响, 初步讨论了催化机理. 结果表明, 具有磺酸根阴离子取代基的水溶性卟啉具有最好的催化活性; 卟啉的催化活性与其在反应体系中的稳定性密切相关; 铁卟啉在反应初期呈现很高的催化活性, 但在光照条件下容易发生光解而导致催化活性的降低; 无金属的磺酸卟啉在催化体系中的催化活性和稳定性最好.  相似文献   

2.
以4-磺酸钾邻苯二腈为原料合成了水溶性四磺酸酞菁(H2PcTS)及其金属配合物(ZnPcTS, FePcTS, CoPcTS), 通过透析法提纯得到了纯度较高的产物. 采用傅里叶变换红外光谱(FTIR)、紫外-可见吸收光谱(UV-Vis)、核磁共振氢谱(1H NMR)及循环伏安(CV)等测试手段表征了四磺酸酞菁及其配合物的结构和性质. 结果表明, 磺酸酞菁在水溶液中存在不同程度的聚集现象, 金属离子的配位会对磺酸酞菁的光谱和电化学性质产生影响. 研究了磺酸酞菁作为光敏剂催化氧化1,5-萘二酚的反应, 发现FePcTS/H2O2催化体系对1,5-萘二酚具有良好的催化氧化性能, 氧化产物主要为5-羟基-1,4-萘醌. 比较了不同溶液pH值对FePcTS和H2PcTS催化能力的影响, 初步探讨了该反应的催化机理.  相似文献   

3.
4.
The chemical behavior of 9-R-sym-octahydroxanthene-1,8-diones and salts based on them in recyclization reactions under the influence of amines was studied. The effect of the basicity of the amines on the direction of recyclization was established. A method is proposed for the single-stage synthesis of sym-octahydroacridine-1.8-dione oximes based on 1,8-dioxo-sym-octahydroxanthenes. Conditions were worked out for the oxidation of sym-octahydroxanthene-1,8-diones and N-R-decahydroacridinediones to the corresponding salts. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 32–38, January, 2006.  相似文献   

5.
报道N-碘代乙酰基-N’-生物素-3,6-二氧杂辛烷-1,8-二胺(4)的简便合成方法。以3,6-二氧杂辛烷-1,8-二氨和D-生物素为原料,经4步反应,高收率(74.9%)地合成了4,其结构经1H NMR确证。  相似文献   

6.
Seven newly synthesized poly(propyleneamine) dendrimers, modified with 1,8-naphthalimides, have been investigated by infrared, UV-vis, and fluorescence spectroscopy. The influence of the nature of the substituents at the C-4 position of the naphthalene ring on the spectral properties of the dendrimers is discussed.  相似文献   

7.
Some new 4-nitro- and 4-allylamino-N-phenyl-1,8-naphthalimides comprising different substituents in the phenyl ring have been studied by infrared absorption spectroscopy. The effect of the nature of the substituents upon the vibration frequencies of the carbonyl groups has been discussed.  相似文献   

8.
The conditions for the formation of N-substituted decahydroacridine-1,8-diones from -R-methylenebiscyclohexane-1,3-diones and 5,5-dimethyl-3-(N-methylamino)-2-cyclohexen-1-one in ethanol, isopropanol, and DMSO have been studied. Methods have been developed for preparation of 1,8-dioxo-10-methyldecahydroacridines which contain furyl and 5-nitrofuryl substituents at the 9 position.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 475–481, April, 2000.  相似文献   

9.
Treatment of [RuCl26-C6H6)]x with bidentate phosphine ligand BDNA [1,8-bis(diphenylphosphinomethyl)naphthalene] in methanol at room temperature gave η6-benzene-ruthenium complexes Ru2Cl46-C6H6)2(μ-BDNA) (1). Complex 1 further reacted with AgBF4 to form complex [Ru2Cl2(μ-Cl)(η6-C6H6)2(μ-BDNA)](BF4) (2). [RuCl26-C6H6)]x reacted with BDNA in refluxing methanol and then the reaction solution was treated with AgBF4 to generate complex [Ru2Cl26-C6H6)2(μ-BDNA)2](BF4)2 (3). Their compositions and structures had been determined by elemental analyses, NMR spectra and single crystal X-ray diffractions. X-ray diffraction showed that complex 1 belonged to monoclinic crystal system, P21/c space group with Z = 4, a = 12.810 Å, b = 21.507 Å, c = 18.471 Å, β = 107.95°; complex 2 belonged monoclinic crystal system, P21/n space group with Z = 4, a = 14.498 Å, b = 15.644 Å, c = 20.788 Å, β = 103.404°, and complex 3 belonged to monoclinic crystal system, P21/n space group with Z = 2, a = 13.732 Å, b = 14.351 Å, c = 19.733 Å, β = 94.82°.  相似文献   

10.
Triethyl ammonium dihydrogen phosphate was used as a cheap and mild acidic ionic liquid catalyst for synthesis of 1,8-dioxo-octahydroxanthenes and bis(indolyl)methanes. This methodology offers several advantages, such as good yields, short reaction times, simple procedure, and mild conditions.  相似文献   

11.
The oxidation of glyoxylic acid (HGl) by MnIVL {L4− = tetra deprotonated 1,8-bis(2-hydroxybenzamido)-3,6-diazaoctane} was investigated in the pH range 1.67-10.18, at 25-45 °C and 0.5 M ionic strength. The reaction exhibited biphasic kinetics with MnIIIL as the reactive intermediate. MnIV was reduced to MnII. The products of oxidation of HGl were identified as formic acid and CO2 in acidic medium, and oxalate in basic medium, consistent with the stoichiometry: −Δ[MnIV]/−Δ[HGl] = 1. In acidic medium, both MnIVL and MnIIIL formed outer-sphere adducts with the neutral HGl {HC(OH)2COOH} molecule, with an association constant Qav of 28 and 70 M−1, respectively. A similar adduct formation was not observed for the glyoxylate mono anion {Gl, CH(OH)2(CO2)} and glyoxylate dianion {Gl2−, CH(OH)(O)CO2}. The rate and activation parameters for the various paths are reported and an outer-sphere electron transfer mechanism is suggested.  相似文献   

12.
Two novel highly photostable blue-emitting 1,8-naphthalimides, containing active fragments of a hindered amine radical scavenger and an s-triazine UV absorber were designed as multifunctional additives capable of simultaneous fluorescent brightening and photostabilization of polymers. Their light absorption and fluorescence properties have been determined and discussed. The ability of the combined fluorescent brighteners to copolymerize with acrylonitrile was demonstrated by obtaining acrylonitrile copolymers with an intense blue fluorescence. Photodegradation of the new fluorophores and their influence on the photostability of the fluorescent copolymers have been studied and compared to other similar 1,8-naphthalimides, not containing either UV absorber or hindered amine fragment in their molecules as well as not containing both of them. Novel fluorophores showed the best photostability in both solution and polymer. A significant photostabilizing effect towards photodegradation of polyacrylonitrile was found.  相似文献   

13.
A new approach for a short synthesis of novel medicinally-important mono-, bis- and tris-1,8-naphthalimide peptidyl derivatives is described. The method generates efficiently 1,8-naphthalimides with variable spacer lengths and charged, polar or hydrophobic residues at desired positions, which can increase binding affinity, conformational stability, intracellular transport and/or biological activity. The synthetic routes reported in this work are both general and applicable, and significantly expand the scope of potential 1,8-naphthalimide anticancer candidates.  相似文献   

14.
A highly selective poly(vinyl chloride) (PVC) membrane electrode based on 1,8-dibenzyl-1,3,6,8,10,13-hexaazacyclotetradecane-Ni(II) as a membrane carrier with unique selectivity toward thiocyanate is reported. The influence of membrane composition, pH and foreign anions were investigated. The sensor exhibits a Nernstian response for thiocyanate over a wide concentration range of 3.3×10−6 to 0.10 M, with a slope 58.4±0.3 mV per decade. The limit of detection is 3.0×10−6 M SCN. The sensor has a response time of <20 s and can be used for at least 2 months without any considerable divergence in potential. The proposed electrode shows fairly a good discriminating ability towards SCN ion in comparison to other anions. It was successfully applied to direct determination of thiocyanate in urine and saliva and it was also used as an indicator electrode in titration of thiocyanate with Ag+ ions.  相似文献   

15.
The 9-aryloctahydroxanthen-1,8-diones (3, 424) were prepared by reaction of cyclohexan-1,3-dione (1) with selected arylaldehydes. The xanthendiones (49, 11, 12, 18, 21, 22) were successfully reacted with chlorosulfonic acid, and the crude sulfonyl chlorides were converted into 15 sulfonamides (2640) for screening as potential pesticides. Attempted chlorosulfonation of the xanthendiones (1317) was unsuccessful. α-Methylcinnamaldehyde was reacted with cyclohexandione (1) to yield the corresponding xanthendione derivative (23). On the other hand, with o-methoxycinnamaldehyde an impure product formed and the p-methoxy isomer afforded the corresponding 2-arylpyran (25). The NMR spectral data of the compounds are briefly discussed.  相似文献   

16.
Some novel fluorescent poly(amidoamine) dendrimers supported by a polyamide-6 matrix have been prepared and studied for the first time. The colour characteristics of the novel materials have been determined and found to be dependent on the nature of 1,8-naphthalimides bonded to their periphery amino groups. The materials have been treated with protons and cuprum cations. The resulting into changes in the colour characteristics and photostability of the dendrimers has been investigated. It has been shown that these ions inhibit the photodegradation of dendrimers molecules studied.  相似文献   

17.
A method for the synthesis of benzylsilanes starting from the corresponding ammonium triflates is reported. Silyl boronic esters are employed as silicon pronucleophiles, and the reaction is catalyzed by copper(I) salts. Enantioenriched benzylic ammonium salts react stereospecifically through an SN2‐type displacement of the ammonium group to afford α‐chiral silanes with inversion of the configuration. A cyclopropyl‐substituted substrate does not undergo ring opening, thus suggesting an ionic reaction mechanism with no benzyl radical intermediate.  相似文献   

18.
A series of aromatic aldehydes are turned in to 3,3,6,6-tetramethyl-9-aryl-1,8-dioxooctahydroxanthene derivatives using trichloroisocyanuric acid(TCCA) as the catalyst.  相似文献   

19.
Cao D  Wang Z  Han C  Cui L  Hu M  Wu J  Liu Y  Cai Y  Wang H  Kang Y 《Talanta》2011,85(1):345-352
Determination of perfluorinated compounds (PFCs) is very important because of their potential hazards to the environment and human health. In present work, 1,8-bis (tetramethylguanidino)-naphthalene (TMGN), a superbasic proton sponge, was firstly employed as the matrix for quantitative detection of acidic PFCs in environmental water samples by Matrix-assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry (MALDI-TOF-MS). Several acidic PFCs, such as perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA), were selected as model analytes for demonstrating the feasibility of the detection method. The results showed that deprotonated ions of these PFCs were detected without any other matrix ions interference. The achieved sensitivity with TMGN for PFOS detection was ten-fold higher than that with 1,8-bis (dimethyl-amino)-naphthalene (DMAN) which was used for the detection of fatty acid by MALDI-TOF-MS. The high sensitivity of this method made it feasible to monitor and quantify acidic PFCs in complicated environmental water samples. Furthermore, a novel combined strategy of solid phase extraction (SPE) followed by MALDI-TOF-MS detection was developed for quantifying PFCs in environmental water samples. The calibration curves with a wide linear dynamic range (0.1-10 ng L−1 for PFOS, PFHxS, and PFBS, and 0.5-50 ng L−1 for PFOA, PFNA, and PFDA.) were obtained. The limit of detection (LOD) for PFOS of this method was 0.015 ng L−1 (a signal-to-noise ratio of 3), which was lower than the LOD (0.036 ng L−1) obtained by high-pressure liquid chromatography/tandem mass spectrometry (LC-MS/MS) method. Moreover, the strategy was used to detect the selected PFCs in water samples collected from Xiaoqinghe river and Gaobeidian wastewater. The achieved concentrations of PFCs were closed to those obtained by LC-MS/MS method. It is indicated that the proposed MALDI-TOF-MS method with TMGN as the matrix is much reliable and can be used as an alternative method to detect trace PFCs in environmental water samples.  相似文献   

20.
A novel highly water-soluble 1,8-naphthalimide with pH and viscosity-sensing fluorescence was synthesized and investigated. The synthesized compound was designed as a molecular device in which a molecular rotor and molecular “off-on” switcher were integrated. In order to obtain a TICT driven molecular motion at C-4 position of the 1,8-naphthalimide fluorophore, a 4-methylpiperazinyl fragment was introduced. The molecular motion was confirmed after photophysical investigation in solvents with different viscosity; furthermore, the fluorescence-sensing properties of the examined compound were investigated in 100% aqueous medium and it was found that it could be used as an efficient fluorescent probe for pH. Due to the non-emissive deexcitation nature of the TICT fluorophore, the novel system showed low yellow–green emission, which represented “power-on”/“rotor-on” state. The protonation of the methylpiperazine amine destabilized the TICT process, which was accompanied by fluorescence enhancement indicating a “power-on”/“rotor-off” state of the system. The results obtained clearly illustrated the great potential of the synthesized compound to serve as pH- and viscosity-sensing material in aqueous solution.  相似文献   

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