This study reports a series of novel heterocyclic hemiindigos (Het‐HI) synthesised via the condensation of indoxyl acetate with various heteroaromatic aldehydes. The influence of electron‐rich and electron‐poor heterocycles on the photochemical and photophysical properties of these compounds have been investigated. Our findings reveal that several Het‐HIs exhibit noteworthy photoswitching behaviour, including enhanced absorption at the visible region. Notably, certain derivatives respond efficiently to green and red light, achieving good conversions to the metastable E‐isomer and displaying prolonged half‐lives of up to 53 days in a polar solvent. The results highlight the potential of these photoswitches for applications in molecular devices and responsive materials.

中文翻译：

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杂环半靛蓝的光化学性质的合成与评价


本研究报道了一系列通过乙酸吲哚酯与各种杂芳醛缩合合成的新型杂环半环二元二酯 （Het-HI）。已经研究了富电子和贫电子杂环对这些化合物的光化学和光物理性质的影响。我们的研究结果表明，几种 Het-HIs 表现出值得注意的光开关行为，包括在可见光区域的增强吸收。值得注意的是，某些衍生物对绿光和红光反应有效，实现了对亚稳 E-异构体的良好转化，并在极性溶剂中显示出长达 53 天的延长半衰期。结果突出了这些光开关在分子器件和响应材料中的应用潜力。