A base-free catalyst system Co(acac)3/BMMImCl was developed for the carbonylation of amines with CO2.45%-81% isolated yields for N,N'-dialkylureas and 6%-23% isolated yields for N,N-diarylureas were obtained.The catalyst system was recovered and reused without significant loss in activity.In this catalyst system,the base catalyst and chemical dehydrant were efficiently avoided.Different reaction conditions were also discussed and a postulated mechanism was proposed.
LI Jian1,2,GUO XiaoGuang1,WANG LiGuo1,2,MA XiangYuan1,ZHANG QingHua1,SHI Feng1* & DENG YouQuan1* 1Centre for Green Chemistry and Catalysis,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou 730000,China 2Graduate University of Chinese Academy of Sciences,Beijing 100039,China
