A highly active and stable imidazolidine-bridged N,O-donor ligand for efficient palladium catalyzed Suzuki-Miyaura reactions in water

We have used the sterically hindered N,O-donor ligand 1,4-bis(2-hydroxy-3,5-di-tert-butyl-benzyl)-imidazolidine with various Pd salts as a catalyst for the Suzuki reaction. This system exhibited excellent catalytic activity in Suzuki reactions of arylboronic acids with aryl halides, including aryl iodides, aryl bromides and activated aryl chlorides, using aqueous methanol as solvent under mild conditions. The catalytic system can be reused once without significant loss of activity. The sterically hindered imidazolidine-bridged mixed nitrogen, oxygen ligand 1 was efficient for Pd-catalyzed Suzuki reactions involving aryl iodides, aryl bromides and activated aryl chlorides with arylboronic acid in aqueous methanol with K2CO3 as a base the high catalytic activity and oxygen or moisture stable of palladium complexes maybe distribute to the bulky tert-butyl effect.