The conversion of CO₂ into valuable chemicals to reduce greenhouse gas emissions has received extensive attention. Converting CO₂ into pharmaceutical intermediates via graphitic carbon nitride (CN) at atmospheric pressure is a challenge. In this work, a series of novel graphitic carbon nitrides (K-CN) catalysts with different doping ratios of K were synthesized by post-treatment of CN with KOH as a dopant under magnetic stirring. Herein, substrates of o-phenylenediamine with different electron-donating/withdrawing groups were employed to convert CO₂ into high-value heterocyclic benzimidazoles. The optimal reaction conditions were determined by a single factor optimization approach. A series of benzimidazole derivatives were synthesized with a yield of up to 96% under atmospheric pressure, indicating that the catalyst can efficiently fix CO₂. This work not only designs a simple and low-cost K-CN catalyst but also provides a new pathway for converting CO₂ into valuable benzimidazole derivatives at atmospheric pressure. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd.

中文翻译：

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K掺杂g-C3N4催化剂催化高效固定CO2常压合成苯并咪唑

_{将CO 2}转化为有价值的化学品以减少温室气体排放已受到广泛关注。在大气压下通过石墨氮化碳(CN)将CO _{2转化为医药中间体是一个挑战。}本工作以KOH为掺杂剂在磁力搅拌下对CN进行后处理，合成了一系列不同K掺杂比例的新型石墨氮化碳（K-CN）催化剂。在此，采用具有不同给电子/吸电子基团的邻苯二胺底物来转化CO ₂转化为高价值的杂环苯并咪唑。通过单因素优化方法确定最佳反应条件。在常压下合成了一系列苯并咪唑衍生物，收率高达96%，表明该催化剂能够有效固定CO ₂。这项工作不仅设计了一种简单、低成本的K-CN催化剂，而且为常压下将CO _{2转化为有价值的苯并咪唑衍生物提供了一条新途径。}© 2023 化学工业协会和 John Wiley & Sons, Ltd.