Synthesis of Tetranuclear Palladium(II) Complexes and Their Catalytic Activity for Cross‐Coupling Reactions

We have developed a short and simple synthesis of tetranuclear palladium(II) complexes which have been structurally confirmed by X-ray analysis. These complexes were formed in about 30 % overall yield by spontaneous metalation of dimethylaminoarene derivatives and exhibit a high stability. We have studied the utility of the tetranuclear palladium(II) complexes as precatalysts for Mizoroki-Heck and Suzuki-Miyaura cross coupling reactions. Our novel complexes show excellent catalytic activities with high turnover numbers and high turnover frequencies (e.g. for the Suzuki-Miyaura reaction: TON up to 538000 and TOF up to 23400 h-1 at room temperature).