文摘
In this Communication, we describe direct arylation reactions with improved scope and catalyst activity for the intramolecular formation of biaryl compounds. This was achieved through the establishment of a highly active and robust catalyst system and the subsequent development of a novel phosphine ligand 27. The enhanced catalytic activity extends these transformations to include previously unreactive and poorly reactive substrates, and allows for very low catalyst loadings to be employed-as little as 0.1 mol %.