Nobel metal like Ir was normally used in these cases. As reported previously, the catalytic amounts of K2CO3 (10 mol%) gave slightly lower conversions compared with the high equivalent amounts of K2CO3. To the best of our knowledge, there is no report for only using catalytic amounts of K2CO3 for the selective oxidation of alcohols, specifically on the oxidation of benzoin, there is no report. In this work, as shown in Since MS 4Å had shown comparable efficiency with K2CO3 in trapping the released water during the alcohol oxidation, which can promote the equilibrium of alcohol oxidation to completion, herein, we first studied the K2CO3 catalytic oxidation of alcohols using additives MS 4Å. First, the amount of K2CO3 from 0%, 5%, 10%, 20%, to 40% were evaluated in the selective oxidation of alcohols using DMSO in an openair system. As shown in the Figure , without the K2CO3, lower than 5% of benzil was obtained. This showed that K2CO3 was necessary in the oxidation process. When the amount of K2CO3 increased from 5% to 40%, at the beginning of the reaction, the product yield increased from 67.0% to 89.4%, which showed the amount of base had a great effect at the beginning of the reaction. These phenomena normally occur at the beginning of the reactions. With the reaction being carried out continuously, the selective oxidation of benzil begins to reach a balance which likely happens after 3 hours. And there was no big change no matter how much amount of K2CO3 was used.