Synthesis of multisubstituted pyrroles by nickel-catalyzed arylative cyclizations of N-tosyl alkynamides.

The synthesis of multisubstituted pyrroles by the nickel-catalyzed reaction of N-tosyl alkynamides with arylboronic acids is reported. These reactions are triggered by alkyne arylnickelation, followed by cyclization of the resulting alkenylnickel species onto the amide. The reversible E/Z isomerization of the alkenylnickel species is critical for cyclization.