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1.
Nine fluoroalkoxyl phthalocyanine metal complexes (Zn, AlCl, Mg, Co, Cu, FeCl) were synthesized from 4-(polyfluoroalkoxyl) phthalic anhydride. The fat-soluble phthalocyanines were characterized by elemental analysis, IR, 1H NMR and fast-atom-bombardment mass spectroscopy. Zinc and aluminum chloride complexes show higher photooxidation ability in solution containing 20% perfluorocarbons than in hydrocarbon solvents.  相似文献   

2.
Jiang  Ming-jian  Li  Xin-yuan  Sun  Lei-tao  Niu  Xiao-long  Liang  Qiu-min  Cai  Xiao-qiang  Huang  Jin-chang  Ling  Jun  Mo  Yue-qi 《高分子科学》2017,35(9):1097-1109
A diquinoxalinopyrene (DQP) derivative and the corresponding oligomers (PDQPs) with Mn of ca.3300,4200,5600,and 7300 have been synthesized.It is found that the band gaps and highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) levels between DQP and its homopolymers only have a slight difference,implying a limited conjugation extension achieved from unimer to heptamer.The DFT calculation is in accordance with the experimental results.It reveals that the nodal planes are across the 2,11-positions in the LUMO and/or HOMO of DQP,dimer and trimer,which can be used to explain this special phenomenon.  相似文献   

3.
A short and efficient synthetic pathway leading to a new chiral π-conjugated system is reported. The X-ray structure of the target compound was determined and showed a helical conformation. Its resolution was successfully accomplished, leading to two enantiomers in high optical purity, and their chiroptical properties were examined experimentally. The photophysical properties of the organic material were also evaluated, showing an emission in the visible region, and HOMO and LUMO levels have been estimated experimentally, demonstrating an electrochemical band gap of 2.37 eV.  相似文献   

4.
Synthesis of 1,3-butadiyne-bridged perfluoroisopropyl binuclear phthalocyanine 2 has been successfully achieved from unsymmetrical A3B-type iodo-perfluoroisopropyl phthalocyanine by palladium-catalyzed cross-coupling with trimethylsilylacetylene and copper-catalyzed Glaser homo-coupling as key reactions. The dyad 2 essentially remains non-aggregated irrespective of solvent and concentration. Electrochemical analysis suggests oxidation is not possible whereas the molecule is more easily reduced. All the results are advantages for photodynamic therapy (PDT).  相似文献   

5.
Some carboxylato-bridged praseodymium(III) complexes (15) having tp [hydrotris(pyrazol-1-yl)borate] and sodium p-X-benzoate (where X =?H, F, Cl, NO2) have been synthesized and characterized by different techniques including X-ray crystallography. The X-ray studies demonstrated that 1, 3 and 5 crystallized in triclinic space group P 1 with cell dimensions a =?11.761(13) Å, b =?12.536(13) Å, c =?17.726(19) Å for 1, a =?9.309(8) Å, b =?12.667(11) Å, c =?14.421(12) Å for 3, a =?11.5688(9) Å, b =?12.0055(9) Å, c =?12.3005(10) Å for 5. In 14 the coordination number of praseodymium is seven, whereas in 5 it is eight. IR suggested that the benzoate groups in 15 are bidentate bridging. The photophysical properties of these complexes have been studied in solution at room temperature. Thermogravimetric analysis showed that these complexes undergo complete decomposition with formation of praseodymium oxide.  相似文献   

6.
Two bromo rhenium(I) carbonyl complexes with the formula of [Re(CO)3(L)Br], where L = 1,10-phenanthroline (Phen-Re) and 5-(1H-pyrrol-1-yl)-1,10-phenanthroline (Pyph-Re), were successfully synthesized with the aim to analyze the effect of the pyrrole (Py) moiety on the photophysical properties of Pyph-Re. It was found that the triplet metal-to-ligand charge-transfer dπ (Re) → π*(N-N) emission of Phen-Re and Pyph-Re centered at ca. 527 nm with the luminescence quantum yield (LQY) of 0.015 and ca. 578 nm with the LQY of 0.011, respectively. At the same time, the geometrical structures of the ground state and the absorption spectral properties of Phen-Re and Pyph-Re were also calculated with the 6-31G* basis set employed on C, H, N, O, and Br atoms, and LANL2DZ adopted on Re atom. According to the experimental and theoretical analysis, the red-shift of the photoluminescent spectrum and the lower LQY of Pyph-Re should be mainly attributed to the narrower energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital and the more LLCT transition ration of Pyph-Re, respectively.  相似文献   

7.
Thermal, photophysical and magnetic properties of some novel fullerenol–silane adducts are described. Excellent improvement of thermal stability and high char yield due to the presence of silicon is the key feature of these adducts. Highest luminescence quenching due to maximum π–π electronic interactions between phenyl ring and fullerene are observed in the aromatic-silane adducts and the quenching ability of the aromatic ring reduces with further delocalization of the π-electrons as in naphthyl silane. The alkyl vinyl silane, on the other hand, records better fluorescence intensity owing to increase population of the electron density (+I effect) and non-effective charge transfer complex formation between isolated vinylic double bond and fullerene. Emission peak positions of these adducts are comparable to fullerenol because of control derivatization of fullerene ring causing less perturbation of the symmetric π-electronic system. These adducts are paramagnetic in nature with peaks around 3515 G and higher g-values (2.005–2.009) compared to fullerenol (1.985). The fullerenol–silane adducts are synthesized using fullerenol as substrate and different chloro and alkoxy silanes as silylating agents adopting simple nucleophilic displacement and transesterification reactions. All the fullerenol–silane adducts are characterized spectroscopically.  相似文献   

8.
Oxygen atom bridged calixarene derivatives called oxacalixarenes were synthesized from bisphenol A and cyanuric chloride by aromatic nucleophilic substitution through addition elimination mechanism. All the synthesized oxacalixarenes exhibit strong absorbance band between 225 and 286?nm due to the presence of triazine and phenoxy units. The oxacalixarenes 7 and 10 show strong fluorescence emission and higher λem values than all other oxacalixarenes due to the presence of rigid aromatic spacer units such as binol and biphenyl. All the oxacalixarenes exhibit quasi-reversible behaviour and potential shift observed in cyclic voltammetry.  相似文献   

9.
Chalcogenide derivatives of triphenylphosphole (oxide (1), sulfide (2) and selenide (3)) were synthesized and characterized by X-ray diffraction studies. Intermolecular interactions were observed in the bulk molecular packing in terms of hydrogen bonding for 1 or π–π stacking for 3. One of the useful applications of the chalcogenide derivatives of triphenylphosphole has been demonstrated utilizing the photophysical properties of 1 to detect aromatic nitro compounds through fluorescence quenching.  相似文献   

10.
The perylene diimide derivatives (s-THBPDI and d-THBPDI) bearing oxygen bridged twisty heptatomic biphenyl in the bay positions of the perylene core through acetylene bond were designed and synthesized. The photophysical properties of the functionalized dyes were investigated in solution and solid state by UV-vis and photoluminescence (PL) spectra. Their UV-vis and PL spectrum both exhibited the different concentration-dependent behaviors due to the difference of chemical structure. Moreover, cyclic voltammetry results indicated that the introduction of oxygen bridged twisted heptatomic biphenyl could decrease the LUMO energy level of the perylene diimide effectively and made it promising material in photoelectric devices.  相似文献   

11.
Five novel lanthanide (Eu3+ (1), Tb3+ (2), Sm3+ (3), Dy3+ (4) and Gd3+ (5)) complexes with 5-Bromonicotinic acid (5-Brnic) were synthesized and two of them (Tb3+, Sm3+) were characterized by X-ray diffraction. The results reveal that {[Tb(5-Brnic)3(H2O)3]·H2O}n (2) and [Sm(5-Brnic)3(H2O)2·H2O]2 (3) exhibit different coordination geometries and crystal structures. Complex 2 has a one-dimensional chain-like polymeric structure through the bridged 5-Brnic anions which links up two neighboring terbium ions, while Complex 3 forms a dimeric molecular structure. The lowest triplet state energy of 5-Brnic was determined to be 24 330 cm−1 corresponded to the 0-0 transition in the phosphorescence spectrum of its gadolinium complex at 411 nm. The strong luminescent emission intensities of these complexes indicated that the triplet state energy of 5-Brnic is suitable for the sensitization of luminescence of Eu3+, Tb3+, Sm3+ and Dy3+, especially for that of Tb3+ and Dy3+.  相似文献   

12.
取代锌酞菁的合成及光物理性质   总被引:14,自引:0,他引:14  
取代锌酞菁的合成及光物理性质张先付,许慧君(中国科学院感光化学研究所,北京,100101)关键词取代酞菁,合成,光物理性质,电荷转移癌症的光动力疗法及其机制是目前光医学、光生物学及光化学的前沿课题[1]。临床应用的光疗药物──血卟啉有一些难以克服的致...  相似文献   

13.
A dimeric complex [Dy(NIC)3(H2O)2]2 (HNIC = pyridine-3-carboxylic acid) has been synthesized. X-ray analysis reveals that it forms a novel dimeric structure through bridged oxygen atoms of carboxylate groups. The title complex crystallizes in space group P21/c, with a = 9.560(3), b = 11.601(4), c = 17.731(5)?Å, β = 91.572(4)°, V = 1965.7(10)?Å3, D c = 1.909?Mg/m3, Z = 2, F(000) = 1100, GOF = 0.956, R 1 = 0.0248. Photophysical properties have been studied with ultraviolet absorption, excitation and emission spectra. The complex exhibits strong blue emission.  相似文献   

14.
Five new coumarin derivatives ( 5a , 5b , 5c , 5d , 5e ) with extending para‐bromophenyl at the 3‐position and substituted vinyl at the 7‐position were synthesized and characterized by FT‐IR, 1H NMR, and element analysis. The absorption and fluorescence characteristics of compounds 5a , 5b , 5c , 5d , 5e showed significant dependences on its molecular structure, which possessed large Stokes shifts (up to 8309 cm?1) and high fluorescence quantum yield (up to 0.80) in CH2Cl2. These advantageous spectral properties should allow use in many areas.  相似文献   

15.
Two new pyrenylamino acid derivatives were synthesized from β-bromodehydroalanine derivatives in good yields using addition and elimination reactions.  相似文献   

16.
The series of complexes [XRu(CO)(L-L)(L′)2][PF6] (X = H, TFA, Cl; L-L = 2,2′-bipyridyl, 1,10-phenanthroline, 5-amino-1,10-phenanthroline and 4,4′-dicarboxylic-2,2′-bipyridyl; L′2 = 2PPh3, Ph2PC2H4PPh2, Ph2PCHCHPPh2) have been synthesized from the starting complex K[Ru(CO)3(TFA)3] (TFA = CF3CO2) by first reacting with the phosphine ligand, followed by reaction with the L-L and anion exchange with NaPF6. In the case of L-L = phenanthroline and L′2 = 2PPh3, the neutral complex Ru(Ph3P)(CO)(1,10-phenanthroline)(TFA)2 is also obtained and its solid state structure is reported. Solid state structures are also reported for the cationic complexes where L-L = phenanthroline, L2 = 2PPh3 and X = Cl and for L-L = 2,2′-bipyridyl, L2 = 2PPh3 and X = H. All the complexes were characterized in solution by a combination of 1H and 31P NMR, IR, mass spectrometry and elemental analyses. The purpose of the project was to synthesize a series of complexes that exhibit a range of excited-state lifetimes and that have large Stokes shifts, high quantum yields and high intrinsic polarizations associated with their metal-to-ligand charge-transfer (MLCT) emissions. To a large degree these goals have been realized in that excited-state lifetimes in the range of 100 ns to over 1 μs are observed. The lifetimes are sensitive to both solvent and the presence of oxygen. The measured quantum yields and intrinsic anisotropies are higher than for previously reported Ru(II) complexes. Interestingly, the neutral complex with one phosphine ligand shows no MLCT emission. Under the conditions of synthesis some of the initially formed complexes with X = TFA are converted to the corresponding hydrides or in the presence of chlorinated solvents to the corresponding chlorides, testifying to the lability of the TFA Ligand. The compounds show multiple reduction potentials which are chemically and electrochemically reversible in a few cases as examined by cyclic voltammetry. The relationships between the observed photophysical properties of the complexes and the nature of the ligands on the Ru(II) is discussed.  相似文献   

17.
Tetraethylammonium chlorochromate(VI), Et4N[CrO3Cl] is easily synthesized in nearly quantitative yield using a direct reaction of chromium(VI) oxide and tetraethylammonium chloride and characterized by elemental analysis, IR, UV/Visible, 1H-NMR and 13C-NMR techniques and single-crystal X-ray diffraction analysis (monoclinic system, space group C2(#5), with a = 12.023(3), b = 7.998(2), c = 14.527(4) Å, β = 114.187(4)°, V = 1274.4(6) Å3 and Z = 4). X-ray data determined the CH ··· O hydrogen bond that forms between the ethyl hydrogen of the cation and oxygen of the anion. This compound is a versatile reagent for efficient and selective oxidation of organic substrates, in particular for alcohols to their corresponding aldehydes or ketones, under mild conditions.  相似文献   

18.
The present work aimed to synthesize a new interesting series of thiazole based polyamides containing diarylidenecyclohexanone moiety 5a-5f using low temperature solution polycondensation technique. The new polymers were synthesized by the reaction of thiazole based monomer namely, bis(2-aminothiazol-4-ylbenzylidene)cyclohexanone 3 with different aliphatic and aromatic diacid chlorides using NMP, and in the presence of anhydrous Li Cl as catalyst. Adipoyl, sebacoyl, oxaloyl, terephthaloyl, isophthaloyl dichlorides and biphenyl dicarbonyl dichloride were used as diacid chlorides. The structure of the model compound 4 as well as the new polymers was confirmed by correct elemental and spectral analyses. The thermal properties of those polymers were evaluated by TGA and DTG measurements and correlated to their structural units, beside X-ray diffraction analysis, solubility and viscometry measurements. The inherent viscosities for the synthesized polymers were in the range 0.6–1.03 d L/g. On the other hand the corrosion inhibitive properties of monomer 3 as well as polyamides 5d and 5f as selected examples were carried out on carbon-steel in 0.5 mol/L H2SO4 at 40 °C. The calculated inhibition efficiency(IE%) for polymer 5d was in the range(82 ± 6)% in all selected concentrations. The best value of IE% was obtained at 1 mg/L to reach 98.24% for polymer 5d and at 0.5 mg/L to reach 87.75% for polymer 5f.  相似文献   

19.
20.
The synthesis and characterization of new peripherally tetra-3,5-dimethylpyrazole-1-methoxy substituted metal-free (4), zinc (5), nickel (6), cobalt (7), copper (8) and lead (9) phthalocyanines are described for the first time in this study. The photophysical (fluorescence quantum yields and fluorescence lifetimes) and photochemical (photodegradation and singlet oxygen quantum yields) properties of metal-free (4), zinc (5) and lead (9) phthalocyanines are studied in dimethylsulfoxide (DMSO). Nickel (6), cobalt (7) and copper (8) phthalocyanines (6-8) did not evaluate for this purpose due to transition metal and paramagnetic behavior of central metals in the phthalocyanine cavity. The fluorescence quenching behavior of metal-free (4), zinc (5) and lead (9) phthalocyanines are also investigated. The fluorescence emissions of these phthalocyanines are effectively quenched by 1,4-benzoquinone in DMSO.  相似文献   

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