Synergistic Effect of a Bis(proazaphosphatrane) in Mild Palladium‐Catalyzed Direct α‐Arylations of Nitriles with Aryl Chlorides

The effect of a bis(proazaphosphatrane) ligand on the palladium‐catalyzed direct α‐arylation of nitriles with various aryl chlorides under mild conditions is reported. Comparisons of the catalytic properties of this ligand with those of three related mono(proazaphosphatrane)s under the same reaction conditions revealed that bis(proazaphosphatrane) displayed a synergistically enhanced activity. In the presence of the bis(proazaphosphatrane) ligand, ethyl cyanoacetate and primary as well as secondary nitriles were efficiently coupled with a wide variety of aryl chlorides that contained electron‐rich, electron‐poor, and electron‐neutral groups.