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介绍了氧化石墨烯作为一种高效且可回收的催化剂应用于2,5-己二酮与苯胺通过Paal-Knorr缩合反应合成N-取代吡咯.研究了反应时间、反应温度、溶剂、催化剂用量以及苯胺与2,5-己二酮的摩尔比对2,5-二甲基-N-苯基吡咯收率的影响.通过原位核磁技术在分子水平上跟踪了Paal-Knorr缩合的反应过程.结果表明在25 ℃下通过氧化石墨烯的催化作用反应6 h后吡咯的最大收率可达到90%.氧化石墨烯易回收,且经5次回收使用后还能表现出很好的循环使用性和高催化性能.“,”Graphene oxide (GO) was used as an efficient and recyclable catalyst for the synthesis of N-substituted pyrrole using a Paal-Knorr condensation reaction between 2,5-hexanedione and aniline.The effects of reaction time, reaction temperature, solvent, catalyst loading and molar ratio of aniline to 2,5-hexanedione on the yield of 2,5-dimethyl-N-phenyl pyrrole were investigated.In situ NMR was used to follow the Paal-Knorr reaction at the molecular level.Results revealed that the oxygen-containing groups of GO, such as sulfonic acid and carboxyl groups, played a key role in this catalytic reaction.Polar protic solvents were favorable for the reaction.The catalytic activity increased with temperature without any side reaction.The GO could be easily recovered and showed remarkable reusability and excellent catalytic performance allowing it to be reused 5 times.