Mahmoudi Asl Aref, Karami Bahador, Farahi Mahnaz, Karimi Zahra
Department of Chemistry, Yasouj University, P. O. Box 353, Yasouj, 75918-74831, Iran.
Heliyon. 2024 Apr 4;10(8):e29277. doi: 10.1016/j.heliyon.2024.e29277. eCollection 2024 Apr 30.
In this study, a novel dual Brønsted acidic-basic nano-scale porous organic polymer catalyst, PC4RA@SiPr-Pip-BuSO3H, was synthesized through various steps: preparation of a 3D network of polycalix, modification with (3-chloropropyl)-trimethoxysilane, then functionalization of polymer with piperazine and -butyl sulfonic acid under the provided conditions. The catalyst characterization was performed by FT-IR, TGA, EDS, elemental mapping, PXRD, TEM, and FE-SEM analyses, confirming high chemical stability, activity, recoverability, and excellent covalent anchoring of functional groups. So, the designed catalyst was utilized for preparing spiro-acenaphthylene and amino-spiroindene heterocycles, providing good performance with a high yield of the corresponding products. Accordingly, this catalyst can be used in different organic transformations. Necessary experiments were conducted for the recyclability test of the polymeric catalyst, and the results showed the PC4RA@SiPr-Pip-BuSO3H catalyst can be reused 10 times without any decrease in its activity or quality with excellent stability. The structure of resultant spiro heterocycles was confirmed using 1H NMR, 13C NMR, and FT-IR.
在本研究中，通过多个步骤合成了一种新型的双布朗斯特酸碱纳米级多孔有机聚合物催化剂PC4RA@SiPr-Pip-BuSO3H：制备多杯芳烃的三维网络，用（3-氯丙基）三甲氧基硅烷进行改性，然后在给定条件下用哌嗪和丁基磺酸对聚合物进行功能化。通过傅里叶变换红外光谱（FT-IR）、热重分析（TGA）、能谱分析（EDS）、元素映射、粉末X射线衍射（PXRD）、透射电子显微镜（TEM）和场发射扫描电子显微镜（FE-SEM）分析对催化剂进行了表征，证实了其具有高化学稳定性、活性、可回收性以及官能团的优异共价锚固。因此，所设计的催化剂用于制备螺苊烯和氨基螺茚杂环，相应产物的产率高，性能良好。因此，该催化剂可用于不同的有机转化反应。对聚合物催化剂进行了可回收性测试的必要实验，结果表明PC4RA@SiPr-Pip-BuSO3H催化剂可以重复使用10次，其活性或质量没有任何下降，稳定性优异。使用1H NMR、13C NMR和FT-IR对所得螺杂环的结构进行了确认。
