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](2)Br-4/[BMIm]BF4. Owing to the multistep operations and the compatibility of MTO and Zn[EMIm](2)Br-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. (c) 2007 Elsevier B.V. All rights reserved.