Green Conversion of CO<sub>2</sub> and Propargylamines Triggered by Triply Synergistic Catalytic Effects in Metal–Organic Frameworks
Xiao‐Lei Jiang, Yue‐E Jiao, Sheng‐Li Hou, Liang‐Chen Geng, Hao‐Zhe Wang, Bin Zhao
Abstract
Abstract Cyclization of propargylamines with CO 2 to obtain 2‐oxazolidone heterocyclic compounds is an essential reaction in industry but it is usually catalyzed by noble‐metal catalysts with organic bases as co‐catalysts under harsh conditions. We have synthesized a unique Cu I /Cu II mixed valence copper‐based framework {[(Cu I 6 I 5 )Cu 3 II L 6 (DMA) 3 ](NO 3 )⋅9DMA} n ( 1 ) with good solvent and thermal stability, as well as a high density of uncoordinated amino groups evenly distributed in the large nanoscopic channels. Catalytic experiments show that 1 can effectively catalyze the reaction of propargylamines with CO 2 , and the yield can reach 99 %. The turnover frequency (TOF) reaches a record value of 230 h −1 , which is much higher than that of reported noble‐metal catalysts. Importantly, this is the first report of heterogeneously catalyzed green conversion of propargylamines with CO 2 without solvents and co‐catalysts under low temperature and atmospheric pressure. A mechanistic study reveals that a triply synergistic catalytic effect between Cu I /Cu II and uncoordinated amino groups promotes highly efficient and green conversion of CO 2 . Furthermore, 1 directly catalyzes this reaction with high efficiency when using simulated flue gas as a CO 2 source.