10.1002/cssc.201902417
ChemSusChem
COMMUNICATION
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through the reaction between substrate 1a and CO2 in the presence of
TMG. TMG presumably plays an important role in enhancing
nucleophilic of 1a and accelerating the nucleophilic attack on the C
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In summary, we have developed a metal-free photocatalysis
system for synthesis of iodine-functionalized 2-oxazolidinones through
the carboxylative cyclization of propargylic amines with CO2 initiated
by molecular iodine. Control experiments and NMR investigations
illuminate the proposed mechanism undergoes a radical path, and I2 is
regarded as radical source. This protocol realizes the incorporation of
CO2 and iodine moiety into exo-iodomethylene oxazolidinone using
visible light as energy input. Importantly, the iodine-substituted 2-
oxazolidinones are able to serve as platform molecules for further
downstream transformations including cross coupling reactions,
photocatalytic ene reaction and photoreduction reaction. In short, this
work represents an alternative example for CO2 conversion driven by
solar energy, and offers a potential tool box for organic synthesis using
CO2 with renewable energy to address energy barrier.
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Acknowledgements
This work was financially supported by National Key Research and
Development Program (2016YFA0602900), National Natural Science
Foundation of China (21672119), China Postdoctoral Science
Foundation (2018M641624).
Keywords: carbon dioxide fixation • carboxylative cyclization • iodine
• photocatalysis • radicals
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Peshkov, O. P. Pereshivko, A. A. Nechaev, A. A. Peshkovc, E. V. V. der
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