Bay-Region Annulative π-Extension of o-Iodobiphenyls with Aliphatic Anhydrides Catalyzed by Pd(OAc)2.

Bay-region annulative π-extension of o-iodobiphenyls with aliphatic anhydrides was developed. Many o-iodobiphenyls and aliphatic anhydrides can react well under the optimized conditions. A lot of phenanthrol derivatives can be efficiently prepared by this approach. The control experiments support that dibenzopalladacyclopentadienes may be the reaction intermediates.