Highly Efficient Organocatalyzed Conversion of Oxiranes and CO2 into Organic Carbonates.
A binary catalyst system based on tannic acid/NBu4X (X=Br, I) is presented as a highly efficient organocatalyst at very low catalyst loading for the coupling of carbon dioxide and functional oxiranes to afford organic carbonates in good yields. The presence of multiple polyphenol fragments within the tannic acid structure is considered to be beneficial for synergistic effects that lead to higher stabilization of the catalyst structure during catalysis. The observed turnover frequencies (TOFs) exceed 200 h(-1) and are among the highest reported to date for organocatalysts in this area of CO2 conversion. This organocatalyst system presents a useful, readily available, inexpensive, and, above all, reactive alternative for most of the metal-based catalyst systems reported to date.
Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007, Tarragona, Spain.
Sergio
S
Sopeña
Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007, Tarragona, Spain.
Giulia
G
Fiorani
Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007, Tarragona, Spain.
Carmen
C
Martín
Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007, Tarragona, Spain. akleij@iciq.es.|Catalan Institute for Research and Advanced Studies (ICREA), Pg. Lluis Companys 23, 08010, Barcelona, Spain. akleij@iciq.es.
Arjan W
AW
Kleij
D002245:Carbon Dioxide / Q000737:chemistry*; D002254:Carbonates / Q000737:chemistry*; D002384:Catalysis; D004852:Epoxy Compounds / Q000737:chemistry*; D013634:Tannins / Q000737:chemistry
D002254:Carbonates; D004852:Epoxy Compounds; D013634:Tannins; D002245:Carbon Dioxide
carbon dioxide; homogeneous catalysis; hydrogen bonding; oxygen heterocycles; ring expansion