Carbopalladation of Nitriles:  Synthesis of Benzocyclic Ketones and Cyclopentenones via Pd-Catalyzed Cyclization of ω-(2-Iodoaryl)alkanenitriles and Related Compounds

An efficient procedure for the synthesis of 2,2-disubstituted benzocyclic ketones by intramolecular carbopalladation of nitriles has been developed. The cyclization of substituted 3-(2-iodoaryl)propanenitriles affords indanones in high yields. The reaction is compatible with a wide variety of functional groups. This methodology has been extended to the synthesis of tetralones and cyclopentenones.