Analogues of isochromenopyrrolone were synthesized using Montomorillonite K10 as a catalyst and characterized. The electronic structure and geometry of all the synthesized compounds were investigated experimentally by UV-visible absorption and fluorescence spectroscopy. A negligible shift was observed in the absorption spectrum while a large red shift was observed in the fluorescence spectrum upon changing from non-polar to polar solvents. The experimental results were compared with those from density functional theory calculations. The observed photophysical properties were induced from the solvent environment. Except for chlorosubstituition, other functional groups like methyl, dimethyl, diethyl or methoxy, did not influence the electronic properties of the molecules significantly. The experimental results were in good agreement with the theoretical interpretations. Moreover, these isochromenopyrrolones possess excellent sensing ability for Fe(III) ions via the fluorescence turn-off mechanism with a detection limit of ∼10⁻⁶ M and an association constant of ∼10³ M⁻¹. It is proposed that these molecules can find their use in environment sensing applications.

中文翻译：

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Fe（iii）的环境依赖性光物理和荧光关闭感应特性由取代的苯基异色吡咯并五酮组成。

以蒙脱石K10为催化剂合成了异色吡咯烷酮的类似物并进行了表征。通过紫外-可见吸收和荧光光谱实验研究了所有合成化合物的电子结构和几何形状。从非极性溶剂变为极性溶剂后，在吸收光谱中观察到的偏移可忽略不计，而在荧光光谱中观察到大的红移。将实验结果与密度泛函理论计算的结果进行了比较。所观察到的光物理性质是由溶剂环境引起的。除氯取代外，其他官能团（如甲基，二甲基，二乙基或甲氧基）不会显着影响分子的电子性能。实验结果与理论解释相吻合。此外，这些异色吡咯烷酮对Fe（III）离子通过荧光关闭机制检测极限为〜10 ^-6 M且缔合常数为〜10 ³ M ^-1。建议这些分子可以在环境传感应用中找到其用途。