Direct preparation of styrene carbonates from styrene using an ionic-liquid-based one-pot multistep synthetic process

• Published in: Applied catalysis. A, General Vol. 333; no. 1; pp. 107 - 113
• Main Authors: Ono, Fumitaka, Qiao, Kun, Tomida, Daisuke, Yokoyama, Chiaki
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 03.12.2007; Elsevier
• Subjects: Carbon dioxide; Carbonate; Catalysis; Chemistry; Epoxidation; Exact sciences and technology; General and physical chemistry; Ionic liquid; Styrene; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Epoxidation; Carbonate; Styrene; Carbon dioxide; Ionic liquid; Heterogeneous catalysis; Hydrocarbon; Preparation; Benzenic compound; Carbonates
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2007.09.015

An ionic-liquid-based one-pot multistep process was investigated for direct synthesis of styrene carbonate from styrene. The whole method was consisted of Methyltrioxorhenium catalyzed epoxidation of styrene with urea hydrogen peroxide to styrene oxide using ionic liquid as solvent in the beginning, and then followed by coupling reaction of styrene oxide with CO 2 by addition of ZnBr 2/ionic liquid as catalyst, and ended with separation of styrene carbonate by m-xylene extraction and recycling of ionic liquid after retrieved by CH 2Cl 2 extraction. A 65% yield of styrene carbonate, the highest one reported so far for this reaction, was obtained, and some other advantages such as higher efficiency of oxidant utilization, easy separation of product and recyclability of ionic liquid were also achieved. ▪ One-pot synthesis of styrene carbonate from styrene is investigated using a multistep protocol in the presence of an ionic-liquid-based catalytic system that is consisted of MTO/UHP/Zn[EMIm] 2Br 4/[BMIm]BF 4. Owing to the multistep operations and the compatibility of MTO and Zn[EMIm] 2Br 4 in ionic liquid, remarkable improvements of the reaction performance regarding the reaction of one-pot synthesis of styrene carbonate from styrene have been achieved. Compared to other methods reported previously concerning this reaction, the current approach can increase the yield of styrene carbonate to 83%. Other improvements such as better utilization percentage of oxidant, easy separation of product and reusability of ionic liquid can also be obtained.