Catalytic Asymmetric Addition of Carbon Dioxide to Propylene Oxide with Unprecedented Enantioselectivity
2006; American Chemical Society; Volume: 8; Issue: 20 Linguagem: Inglês
10.1021/ol061501d
ISSN1523-7060
AutoresAlbrecht Berkessel, M. Brandenburg,
Tópico(s)Catalysts for Methane Reforming
ResumoNew chiral catalyst systems were developed for the reaction of carbon dioxide with propylene oxide (PO) at atmospheric pressure to generate enantiomerically enriched propylene carbonate (PC). The best selectivity was achieved with a CoIII(salen)−trifluoroacetyl complex and bis(triphenylphosphoranylidene)ammonium fluoride (PPN+F-) as catalysts, affording PC in 40% yield and 83% ee (selectivity factor = 19). In addition, PC was prepared for the first time by kinetic resolution of PO with tetrabutylammonium methyl carbonate (TBAMC, nBu4N+-OOCOMe). With TBAMC as "activated CO2", up to 71% ee was obtained.
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