Application of the Fluorous Biphase Concept to Palladium-CatalyzedSuzuki Couplings

Abstract

Suzuki C−C couplings were performed in high yields in a fluorous biphase system applying the four differently perfluoro-tagged Pd complexes 2a – d. All four complexes showed similar catalytic activities in the coupling of electron-rich or electron-deficient bromoarenes 3a – e and arylboronic acids 4a – c (Tables 1 and 2). Furthermore, we were able to show that all four Pd complexes could be recycled six times without significant decrease in coupling yield. In one example, we were able to reduce the amount of the four catalysts from 1.5 mol-% to 0.1 mol-% in the first runs, but with considerable loss of catalyst activity in repetitive cycles (Table 3).