Designing highly efficient heterogeneous catalysts for the Friedel–Crafts acylation (FCA) reaction is a very significant subject for the development of green chemical industry. Herein, a series of nanosized iron carbide-encapsulated N-doped porous carbons (Fe_xC/NC-n) have been prepared through high-temperature pyrolysis of the Fe-Zn bimetallic organic framework for the catalytic application in FCA of aromatic compounds with acyl chlorides. A variety of characterization results demonstrated that the nanosized iron carbides (Fe_xC), which are wrapped inside of the graphitic carbon shell, are the main active sites for the FCA reaction. Changing the ratios of Fe/Zn can considerably influence the particle size of Fe_xC and the thickness of the graphitic carbon shell. The composition-optimized catalyst, named as Fe_xC/NC-0.05, exhibited the highest activity and excellent recyclability for the reaction. The relatively thin graphitic carbon shell allows rapid penetration of reagents and, meanwhile, can also provide effective protection for the active Fe_xC particles against leaching by space confinement and electronic effects, thus resulting in the formation of highly active and stable Fe_xC/NC-n catalysts for the FCA reaction.

中文翻译：

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N掺杂的多孔碳– Fe _x C纳米颗粒复合材料作为弗里德尔-克拉夫特酰化反应的催化剂

设计用于弗瑞德-克拉夫茨酰化（FCA）反应的高效多相催化剂是绿色化学工业发展的重要课题。在此，通过Fe-Zn双金属有机骨架的高温热解，制备了一系列纳米_尺寸的碳化铁包埋的N掺杂的多孔碳（Fe _x C / NC- n），以催化芳族化合物在FCA中的催化应用。酰氯。各种表征结果表明，包裹在石墨碳壳内部的纳米级碳化铁（Fe _x C）是FCA反应的主要活性部位。改变Fe / Zn的比例会大大影响Fe _x的粒径C和石墨碳壳的厚度。成分优化的催化剂名为Fe _x C / NC-0.05，显示出最高的活性和优异的可回收性。相对薄的石墨碳壳可以快速渗透试剂，同时还可以有效保护活性Fe _x C颗粒不受空间限制和电子效应的浸出，从而形成高活性和稳定的Fe _x C /用于FCA反应的NC- n催化剂。