Green Conversion of CO and Propargylamines Triggered by Triply Synergistic Catalytic Effects in Metal-Organic Frameworks.

Cyclization of propargylamines with CO 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 /Cu mixed valence copper-based framework {[(Cu I )Cu L (DMA) ](NO )⋅9DMA} (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 , and the yield can reach 99 %. The turnover frequency (TOF) reaches a record value of 230 h , 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 without solvents and co-catalysts under low temperature and atmospheric pressure. A mechanistic study reveals that a triply synergistic catalytic effect between Cu /Cu and uncoordinated amino groups promotes highly efficient and green conversion of CO . Furthermore, 1 directly catalyzes this reaction with high efficiency when using simulated flue gas as a CO source.