A novel diol-functionalized poly(ethylene glycol)-bridged dicationic ionic liquid ([diol-PEG1000-DIL][PF6]) is prepared and used as an efficient and reusable ligand for copper-catalyzed amination. A variety of aryl iodides and aryl bromides reacted smoothly with aqueous ammonia to afford the corresponding aromatic primary amines in good to excellent yields. It is remarkable that aryl chlorides with a strong electron-withdrawing group exhibited a dramatically elevated activity in the presence of tetrabutylammonium bromide. Furthermore, the catalyst could be easily recovered and reused without obvious loss of catalytic activity after five recycling runs.
Box–Behnken design for removal of uranium(VI) from aqueous solution using poly(ethylene glycol) based dicationic ionic liquid impregnated chitosan
