共查询到18条相似文献,搜索用时 640 毫秒
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合成了一系列新型的6-氯-8-溴-螺吡喃光致变色化合物, 并用核磁共振氢谱、红外光谱、质谱和元素分析对目标化合物进行了表征, 利用X射线单晶衍射仪测定了1′,5′-甲基取代化合物的晶体结构.通过UV-Vis光谱对化合物在不同溶剂中的光致变色性能进行了研究, 讨论了溶剂和结构对光致变色性能的影响.在极性较大的溶剂中, 光致变色现象明显; 给电子能力较强的基团和强极性溶剂使最大吸收波长蓝移. 相似文献
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合成了一系列新型的6-氯-8-溴-螺吡喃光致变色化合物,并用核磁共振氢谱、红外光谱、质谱和元素分析对目标化合物进行了表征,利用X射线单晶衍射仪测定了1′,5′-甲基取代化合物的晶体结构.通过UV-Vis光谱对化合物在不同溶剂中的光致变色性能进行了研究,讨论了溶剂和结构对光致变色性能的影响.在极性较大的溶剂中,光致变色现象明显;给电子能力较强的基团和强极性溶剂使最大吸收波长蓝移. 相似文献
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聚乙二醇支载的螺吡喃类光致变色化合物的合成及其逆光致变色性质 总被引:6,自引:0,他引:6
采用DCC缩合的方法,将吲哚啉螺苯并吡喃的衍生物和聚乙二醇相缩合,以聚乙二醇末端的羟基和吲哚啉螺苯并吡喃衍生物的羧基为反应活性基团,实现了带有羧基的螺吡喃类光致变色化合物支载到了聚乙二醇两端.通过引入亲水基团得到了水溶性较好的螺环类光致变色化合物.通过对产物的紫外-可见光谱的研究发现,产物具有良好的光致变色性质,在乙醇、丙酮和乙酸乙酯中皆具有良好的光致生色现象;产物可溶于水,在紫外光(波长365nm)照射时产生了光消色现象,具有明显的逆光致变色性质.该方法原料易得,反应条件容易控制,为光致变色新材料的研究和开发提供了新方法. 相似文献
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Tanaka M Nakamura M Salhin MA Ikeda T Kamada K Ando H Shibutani Y Kimura K 《The Journal of organic chemistry》2001,66(5):1533-1537
Spirobenzopyran derivatives carrying an oxymethylcrown ether moiety were synthesized, and their photochromism was studied in the presence of various metal ions in acetonitrile. The metal ion complexing ability of the crown ether moiety in crowned spirobenzopyrans affects both thermal isomerization and photoisomerization of their spirobenzopyran moiety to a great extent. When the interaction of the crown ether moiety with a metal ion was strong enough to cause thermal isomerization of the spirobenzopyran moiety to its corresponding merocyanine form and to suppress UV-induced isomerization to the merocyanine form, a negative photochromism appears. On the other hand, a relatively weak interaction of the crown ether moiety with a metal ion affords a positive photochromism. This phenomenon enables us to switch the photochromic behavior between positive and negative photochromisms. 相似文献
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Kiyotaka Shigehara Haruo Matsunaga Eishun Tsuchida 《Journal of polymer science. Part A, Polymer chemistry》1978,16(8):1853-1863
Some polymeric azine or thiazine dyes were prepared by radical polymerization of dye monomers or by polymer reactions between dyes and suitable prepolymers, and their photoredox reactivities were studied. The thionine polymers containing labile ? OH groups exhibited photochromism and thermochromism, which were extremely sensitive to the moisture content of the polymer film. The reversibility of the photochromism and thermochromism increased with the water content in the film. The water-soluble polymeric dyes were photobleached under the influence of suitable reducing agents. The degree of photobleaching was smaller than for the monomeric systems except for the dye polymers containing ? OH groups, probably because of the large steric hindrance of the polymers. 相似文献
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Kenji Kinashi Yoko Ono Yukito Naitoh Akira Otomo Yasukiyo Ueda 《Journal of photochemistry and photobiology. A, Chemistry》2011,217(1):35-39
The excited state dynamics of the photomerocyanine (PMC) form originating from spirobenzopyran and the bi-functional photochromic compound spirobenzopyran–azobenzene (SpAz), containing typical photochromic molecules of spirobenzopyran (Sp) and azobenzene (Az), were investigated using picosecond time-resolved fluorescence measurements in solution at 200 and 285 K and in a PMMA polymer film at 298 K. While the fluorescence lifetimes of PMC were about twice as long as those of SpAz under all experimental conditions, both lifetimes showed similar strong dependence on viscosity rather than temperature. These results suggest that non-radiative decay to an intermediate state could be accompanied by a significant conformational change. The effect of the Az moiety in this relaxation process is also discussed. It is unlikely that an energy transfer from the PMC moiety to the Az moiety occurs. It was concluded that the PMC moiety in the bi-functional SpAz is independent from the Az moiety. 相似文献
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Tanaka M Kamada K Ando H Kitagaki T Shibutani Y Kimura K 《The Journal of organic chemistry》2000,65(14):4342-4347
Spirobenzothiapyrans bearing monoaza-12-crown-4, -15-crown-5, -18-crown-6, and oligooxyethylene moieties were synthesized, and their photochromism was examined in the presence of cations in acetonitrile. The cation complexation by their crown ether moieties cannot induce thermal isomerization to their corresponding colored merocyanine form, unlike the corresponding spirobenzopyran derivatives. The UV-light-induced isomerization was, however, facilitated by the cation complexation of the crown ether moieties and the affinity of the merocyanine thiophenolate anion to metal ions, especially in the presence of Li(+) and Ag(+). The presence of Ag(+) brought about the most remarkable effect in the facilitation of photoisomerization of the spirobenzothiapyrans and the thermal stability of the colored merocyanine form mainly due to the powerful interaction of the thiophenolate anion with the soft metal ion. 相似文献
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In this paper, the polyanion-containing cinnamoyl group (PACSS-CF3) was self-assembled with diazoresin (DR) to form a kind of stable covalent ultrathin film by irradiation with 365?nm UV light. The photoalignment properties of the DR/PACSS-CF3 covalent film were investigated. The covalent film was found to have anisotropy after irradiation by 297?nm linearly polarised ultraviolet light (LPUVL), and could induce uniform alignment of liquid crystals (LCs). The pretilt angle of the LC was 2.5°. The stability of the film was enhanced by the covalent bonds. The films were thermally stable to 180°C. Polarised UV-Vis spectroscopy was utilised to investigate the photochemical process of the covalent film. It was found that cinnamoyl moieties parallel to the polarisation direction of the LPUVL were consumed by the photoreaction faster than those perpendicular to the polarisation direction. It can be concluded that the selective photoreaction induced the anisotropy of the films. The anisotropic films induced the homogeneous alignment of LC. 相似文献
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Kameda M Sumaru K Kanamori T Shinbo T 《Langmuir : the ACS journal of surfaces and colloids》2004,20(21):9315-9319
The dielectric environment surrounding poly(N-isopropylacrylamide) in aqueous solution was investigated by probing with spirobenzopyran covalently attached as a side chain to the polymer main chain. Inherent characteristics of the spirobenzopyran chromophore were analyzed, and the chromophore was confirmed to be suitable to probe the local polar condition around the polymer. Measurements for an aqueous polymer solution at various temperatures elucidated that the dielectric environment surrounding the polymer changed continuously even in the temperature range far below the lower critical solution temperature. This result suggested that the local and weak orientation of water molecules around the polymer diminished continuously in a preliminary stage of shifting to thermally induced phase separation. The dielectric environment surrounding thermoresponsive polymer in aqueous solution was investigated by probing with spirobenzopyran covalently attached as a side chain to the polymer main chain. 相似文献
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Hiroyuki Nakazumi Koichiro Makita Rie Nagashiro 《Journal of Sol-Gel Science and Technology》1997,8(1-3):901-909
New photochromic thin gel films have been prepared by the dipping method from a sol-gel coating solution containing Malachite
Green Leucocyanide soluble in sol and super-fine dispersed solution of spiropyran or spironaphthooxazine, which was effective
to increase the concentration of photochromic compounds in gel film. Photochromism of these gel films is compared with that
in sol under the conditions of acid catalysis. Though in sols using spiropyran and Malachite Green Leucocyanide normal photochromism
was not observed, photochromism in thin gel films prepared from the same sol was confirmed. Normal photochromism of spironaphthooxazine
in thin gel films was similar to that in solution. The reaction rate from the colored form to the spiro form of spiropyran
and spironaphthooxazine in thin gel film is dependent on the gel matrix, which is influenced by the reaction time of the sol. 相似文献
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Yang T Pu S Fan C Liu G 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(5):1065-1072
A new unsymmetrical photochromic diarylethene, 1-(2-methyl-5-phenyl-3-thienyl)-2-[2-methyl-5-(3-trifluoromethylphenyl)-3-thienyl]perfluorocyclopentene (1a), was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. Its optical and electrochemical properties, including photochromic reactivity both in solution and in the solid state (PMMA film and the single-crystalline phase), fluorescence and electrochemical properties were investigated in detail. The compound showed excellent photochromism even in the single-crystalline phase by photo-irradiation. In acetonitrile, the open-ring isomer of diarylethene 1 exhibited relatively strong fluorescence at 470nm when excited at 300nm, and its emission intensity decreased along with the photochromism upon irradiation with 313nm light. Its closed-ring isomer showed almost no fluorescence. The electrochemical properties of diarylethene were investigated by performing cyclic voltammetry experiment and its HOMO and LUMO energy level were calculated. 相似文献