Modified melamine-based porous organic polymers with imidazolium ionic liquids as efficient heterogeneous catalysts for CO2 cycloaddition

Yi Liu; Shuangjiang Li; Ying Chen; Tianding Hu; Manoj Pudukudy; Lan Shi; Shaoyun Shan; Yunfei Zhi

doi:10.1016/j.jcis.2023.07.127

Modified melamine-based porous organic polymers with imidazolium ionic liquids as efficient heterogeneous catalysts for CO₂ cycloaddition

J Colloid Interface Sci. 2023 Dec 15;652(Pt A):737-748. doi: 10.1016/j.jcis.2023.07.127. Epub 2023 Jul 21.

Authors

Yi Liu¹, Shuangjiang Li¹, Ying Chen², Tianding Hu¹, Manoj Pudukudy³, Lan Shi¹, Shaoyun Shan⁴, Yunfei Zhi⁵

Affiliations

¹ Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China.
² Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China; Sichuan Vocational College of Chemical Technology, Luzhou, Sichuan 646300, PR China.
³ Department of Chemistry, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Thandalam, Chennai 602105, Tamil Nadu, India.
⁴ Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China. Electronic address: shansy411@163.com.
⁵ Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, PR China. Electronic address: zyf891123@163.com.

PMID: 37500314
DOI: 10.1016/j.jcis.2023.07.127

Abstract

The chemical conversion of carbon dioxide (CO₂) into highly value-added products not only alleviates the environmental issues caused by global warming but also makes an impact on economic benefits in the world. The synthesis of cyclic carbonates by the cycloaddition of CO₂ with epoxides is one of the most attractive methods for CO₂ conversion. However, the development of green and highly efficient heterogeneous catalysts is considered to be a great challenge in catalysis. In this work, alkenyl-modified melamine-based porous organic polymer (MPOP-4A) was firstly synthesized by a one-pot polycondensation method, and it was again modified with imidazolium-based ionic liquids to obtain final modified catalyst (MPOP-4A-IL). Various analytical techniques were used to confirm structure and chemical composition of the prepared materials. The MPOP-4A-IL catalyst synthesized by the post-modification strategy with imidazolium-based ionic liquids exhibited enhanced catalytic activity for CO₂ cycloaddition reaction. The enhanced catalytic performance could be attributed to the presence of abundant active sites in their structure such as hydrogen bond donors (HBD), nitrogen (N) sites, and nucleophilic groups for an effective chemical reaction. The MPOP-4A-IL catalyst was found to be metal-free, easy to recycle and reuse, and has good versatility for a series of different epoxides. The interaction of MPOP-4A-IL catalyst with epoxide and CO₂ was further verified by density functional theory (DFT) calculations, and the possible mechanism of the CO₂ cycloaddition reaction was proposed.

Keywords: CO(2) cycloaddition; Density functional theory calculations; Ionic liquids; Melamine-based porous organic polymer; Multifunctional catalyst.