Electroreductive Pd-Catalyzed Ullmann Reactions in Ionic Liquids

摘要

A catalytic alternative to the Ullmann reaction is presented, based on reductive homocoupling catalyzed by palladium nanoparticles. The particles are generated in situ in an electrochemical cell, and electrons are used to close the catalytic cycle and provide the motivating force for the reaction. This system gives good yields using iodo- and bromoaryls, and requires only electricity and water. Using an ionic liquid solvent combines the advantages of excellent conductivity and cluster stabilising.