高效的可逆Z-E光异构化与可见光通过分辨率S(1)(n pi*) 的吸收带桥接阿佐烯的可见光
Ron Siewertsen1, Hendrikje Neumann, Bengt Buchheim-Stehn
1Institut für Physikalische Chemie, Christian-Albrechts-Universität zu Kiel, Olshausenstr. 40, D-24098 Kiel, Germany.
Journal of the American Chemical Society
|October 16, 2009
概括
这项研究探讨了一个受约束的桥梁阿佐本衍生物的Z-E光交换. 其有利的光色特性使其成为一个有前途的分子光开关,特别是在低温下.
科学领域:
- 摄影化学的使用.
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 亚二衍生物因其光交换能力而受到广泛研究.
- 受到约束的分子结构可以显著改变光化学性质.
- 了解结构属性关系是设计先进分子开关的关键.
研究的目的:
- 为了研究一个严重受限制的桥接亚博烯衍生物的可逆Z-E光交换特性,5,6-二二[c,g][1,2]diazocine (1).
- 量化评估其光色行为,并将其与正常的亚博 (AB) 进行比较.
- 为了评估其作为分子光开关的潜力.
主要方法:
- 在n-hexane溶液中进行紫外线/紫外线吸收光谱.
- 对Z-E异构化效率和量子产量的定量分析.
- 测量E异构体的热寿命.
主要成果:
- 化合物 (1) 在lambda(Z) = 404 nm和lambda(E) = 490 nm处表现出分离良好的S(1)(n pi*) 吸收带.
- 使用385nm光线,从1Z切换到1E的高切换效率 (Gamma = 92 +/- 3%).
- 从1E到1Z的高效反向切换 (大约. 100%的产量) 使用520nm光.
- 量子收益率:Phi(Z-->E) = 72 +/- 4%,而Phi(E-->Z) = 50 +/- 10%.
- 在28.5°C的温度下,E异构体的热寿命为4.5 +/- 0.1小时.
结论:
- 受约束的桥接阿佐烯衍生物 (1) 显示了比正常的阿佐烯显著更有利的光色和光交换特性.
- 乙烯桥束增强,而不是阻碍Z-E光异构化反应.
- 这种化合物是分子光开关应用的有希望的候选物,特别是在低温下.
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