PEG Click-Triazole Palladacycle: An Efficient Precatalyst for Palladium-Catalyzed Suzuki-Miyaura and Copper-free Sonogashira Reactions in Neat Water

A novel water-soluble, phosphine-free PEG click triazole palladacycle has been successfully synthesized. As a precatalyst, the palladacycle exhibited superior catalytic activity towards Suzuki-Miyaura and copper-free Sonogashira cross-coupling in neat water with the turnover numbers (TONs) of up to 9.8x10(5). In addition, the catalyst could be reused at least 3 times without significant loss of reactivity.