Palladium-Catalyzed Suzuki−Miyaura Cross-Coupling Reactions of Potassium Aryl- and Heteroaryltrifluoroborates

Abstract
An extended study of the reactivity of potassium aryl- and heteroaryltrifluoroborates in Suzuki-Miyaura cross-coupling reactions is presented. The coupling of aryl- and electron-rich heteroaryltrifluoroborates with aryl and activated heteroaryl bromides proceeds readily under ligandless conditions. When deactivated aryl- and heteroaryltrifluoroborates are coupled with aryl and heteroaryl bromides and chlorides, a low loading (0.5−2%) of PdCl2(dppf)·CH2Cl2 efficiently catalyzes the reactions. Under either condition, reactions can generally be carried out in an open atmosphere.