Catalytic Asymmetric Cycloaddition of Carbon Dioxide and Propylene Oxide Using Novel Chiral Polymers of BINOL-Salen- Cobalt(III) Salts
نویسندگان
چکیده
Four new chiral polymers of BINOLSalen-cobalt ACHTUNGTRENNUNG(III) salt complexes have been designed, synthesized and applied to the direct fabrication of chiral propylene carbonate from racemic propylene oxide. The (R/S)-polymer catalyst 2 and (S/R)-polymer catalyst 4 exhibit better enantioselectivity than the (R/R)-polymer catalyst 1 and the (S/S)-polymer catalyst 3 and have been recovered and reused more than ten times without loss of activity and enantioselectivity.
منابع مشابه
Catalytic asymmetric addition of carbon dioxide to propylene oxide with unprecedented enantioselectivity.
New 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 Co(III)(salen)-trifluoroacetyl complex and bis(triphenylphosphoranylidene)ammonium fluoride (PPN+F-) as catalysts, affording PC in 40% yield and 83% ee (selectivity...
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