Carbon-Carbon Bond Formation Facilitated by π-Complexed Organometallic Auxiliaries: An Overview

: Organometallic moieties attached to substrates via π-complexation play an important role as auxiliaries. As described in the present review, η-linked auxiliaries have been employed to overcome numerous synthesis obstacles that continue to present significant challenges for catalyzed reactions. This has been particularly true in carbon-carbon bond forming reactions involving highly unsaturated systems such as arenes, dienes and allenes, which are emphasized here.