The first use of porphyrins as catalysts in cross-coupling reactions:a water-soluble palladium complex with a porphyrin ligand as an efficient catalyst precursor for the Suzuki-Miyaura reaction in aqueous media under aerobic conditions

摘要

For the first time,a palladium complex with a porphyrin ligand is used as a catalyst precursor for cross-coupling reactions.The synthesis of a palladium complex with a phosphine-free and water-soluble potassium carboxylate salt of a porphyrin,and its evaluation in the Suzuki-Miyaura reaction of phenylboronic acid with aryl bromides(from electron-rich to electron-poor),in neat water,under aerobic conditions is described.Catalysis is performed at 100 °C for 4 h,using K2CO3 as base,and a substrate to catalyst molar ratio of 1000:1,leading to yields of coupling products in the range of 80-100%.The catalyst can be recycled and reused,but unfortunately,with a loss in activity.