54758-72-4Relevant academic research and scientific papers
Computer-aided rational design of Fe(iii)-catalysts for the selective formation of cyclic carbonates from CO2 and internal epoxides
Sinha, Indranil,Lee, Yuseop,Bae, Choongman,Tussupbayev, Samat,Lee, Yujin,Seo, Min-Seob,Kim, Jin,Baik, Mu-Hyun,Lee, Yunho,Kim, Hyunwoo
, p. 4375 - 4387 (2017)
The catalytic mechanism of the cyclic carbonate formation reaction between CO2 and internal epoxides promoted by Fe-salen and the Kleij catalyst was examined in detail to better understand how the catalytic efficiency can be increased. Specifically, we aimed to make the catalyst more chemoselective towards forming cyclic carbonates and preventing the competing side reaction leading to polycarbonates via ring-opening polymerization. A few rational design principles were derived and first tested using computer models based on density functional theory. The most promising candidate that was identified in the computer model was then prepared and found to display significantly enhanced reactivity towards forming the cyclic carbonates, supporting the validity of the mechanistic insights deduced from the computer simulations. We propose that a cyclic carbonate is formed most efficiently via an inner-sphere mechanism where both the CO2 and epoxide substrates utilize the metal center for the key bond forming events. In contrast, the ring-opening polymerization uses an outer-sphere mechanism, where a carbonate attacks and ring-opens the epoxide bound to the metal without engaging the metal directly. These mechanistic differences are exploited to implement a chemoselective catalyst by enhancing the rate of the cyclic carbonate formation reaction while leaving the polymerization pathway largely unaffected.
Catalysts for polycarbonate production
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Page/Page column 67, (2021/12/02)
The present invention provides unimolecular metal complexes having increased activity in the copolymerization of carbon dioxide and epoxides. Also provided are methods of using such metal complexes in the synthesis of polymers. According to one aspect, the present invention provides metal complexes comprising an activating species with catalytic activity tethered to a ligand that is coordinated to the active metal center of the complex.
METAL CATALYSTS FOR SELECTIVE FORMATION OF CYCLIC CARBONATES, PROCESS FOR PREPARING CYCLIC CARBONATE USING THE SAME AND USE OF CYCLIC CARBONATE
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Paragraph 0091; 0092; 0093; 0094, (2017/04/11)
Provided are a novel metal catalyst for preparing cyclic carbonate, and a method for preparing cyclic carbonate using the same, and more particularly, a method for selectively preparing cyclic carbonate in a high yield and at a higher conversion rate as compared to the existing catalysts, using the metal complex including a ligand represented by Chemical Formula 1 below and a trivalent metal in Group 8 or Group 13 as a catalyst and using various structures of epoxide compounds and carbon dioxide as raw materials. In addition, provided are the prepared cyclic carbonate, and an electrolyte including the same: in Chemical Formula 1, R1 is hydrogen, (C1-C20)alkyl or halogen; R2 is hydrogen, (C1-C20)alkyl, (C1-C20)alkoxy, halogen or nitro.
