Development of a method for preparing a highly reactive and stable, recyclable and environmentally benign organopalladium catalyst supported on sulfur-terminated gallium arsenide(001): A three-component catalyst, {Pd}-S-GaAs(001), and its properties

We have developed a method for preparing a recyclable and environmentally benign organo-palladium catalyst for the Heck reaction supported on sulfur-terminated gallium arsenide(001). This three-component catalyst, {Pd}-S-GaAs(001), exhibited high stability and activity, furthermore. it tolerated reuse in 10 runs of the Heck reaction (average yield, 97%) under aerobic conditions. The sulfur layer was very important to stabilize this catalyst. Only trace amounts of Pd were leached from this catalyst to the reaction mixture, as measured by ICP-mass. The valence of immobilized Pd was zero by XPS spectrometry.