Moazzen Behrang, Kamrouz Roya, Khorshidi Alireza
Faculty of Chemistry, University of Guilan, P. O. Box: 41335-1914, Rasht, Iran.
Sci Rep. 2025 Jan 2;15(1):250. doi: 10.1038/s41598-024-83968-2.
The catalytic efficiency of sulfonated polystyrene foam waste (SPS) and sulfonated gamma alumina (SGA) in Friedel-Crafts type reactions was compared. All of the materials were studied using the state-of-the-art characterization techniques. SPS was found to carry a higher load of -SOH functional groups (1.62 mmol H per g) compared to SGA (1.23 mmol H per g), contributing to its slightly higher efficiency in the regioselective ring-opening of 2-(phenoxymethyl)oxirane with indole. Under mild and solvent-free conditions, SPS catalyzed the reaction of various indoles and oxiranes (9 examples) with acceptable yields (55-99%). The catalyst's efficiency was further validated in synthesizing various bis(indolyl)methanes (8 examples, 88-99% yield). Recyclability tests confirmed the stability of SPS over multiple cycles, maintaining significant catalytic activity. This study highlights the potential of SPS as a sustainable and efficient catalyst, offering a greener alternative to conventional methods and promoting the valorization of plastic waste in organic synthesis.
比较了磺化聚苯乙烯泡沫废料（SPS）和磺化γ-氧化铝（SGA）在傅克型反应中的催化效率。所有材料均采用最先进的表征技术进行研究。结果发现，与SGA（每克1.23毫摩尔氢）相比，SPS负载的-SOH官能团含量更高（每克1.62毫摩尔氢），这使得其在2-（苯氧基甲基）环氧乙烷与吲哚的区域选择性开环反应中效率略高。在温和且无溶剂的条件下，SPS催化了各种吲哚与环氧乙烷（9个实例）的反应，产率可接受（55-99%）。该催化剂在合成各种双（吲哚基）甲烷（8个实例，产率88-99%）中的效率得到进一步验证。可回收性测试证实了SPS在多个循环中的稳定性，保持了显著的催化活性。这项研究突出了SPS作为一种可持续且高效催化剂的潜力，为传统方法提供了更绿色的替代方案，并促进了有机合成中塑料废料的增值利用。
