Crystalline-gradient polycarbonates prepared from enantioselective terpolymerization of meso-epoxides with CO2
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چکیده
منابع مشابه
Crystalline CO2-based polycarbonates prepared from racemic catalyst through intramolecularly interlocked assembly
The crystalline stereocomplexed polycarbonates can be prepared by mixing enantiopure polymers with opposite configuration, which derived from the asymmetric copolymerization with CO2 using enantiopure catalyst or/and chiral epoxides. Herein, we develop a powerful strategy for producing crystalline intramolecular stereocomplexed polycarbonates from racemic catalysts, which possess similar therma...
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Three interconnected catalytic cycles account for the title reaction catalyzed by a bimetallic aluminum(salen) complex and Bu(4)NBr. In the first, Bu(4)NBr acts as a nucleophile to activate the epoxide. In the second, Bu(3)N generated in situ serves to activate CO(2). In the third, the aluminum(salen) complex brings the two activated species together so that the key bonds can be formed intramol...
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ژورنال
عنوان ژورنال: Nature Communications
سال: 2014
ISSN: 2041-1723
DOI: 10.1038/ncomms6687