Iron-Catalyzed Cross-Coupling Reactions Tuned by Bulky Ortho-Phenylene Bisphosphine Ligands

Abstract The significant progress made in the context of iron-catalyzed cross-coupling reactions in the past several years has boosted competition with well-known nickel and palladium catalyst systems. Iron-catalyzed protocols not only benefit from economic and toxicology standpoints, but also exhibit a range of reactivities and tolerate many functional groups. To date several iron catalyst systems have been developed, ranging from the use of simple iron salts to more complex stoichiometric/catalytic modifiers. Effective N-heterocyclic carbenes and bisphosphine ligands have also been developed for the cross-coupling reactions of organic electrophiles using diverse organometallic reagents. Indeed, the use of bisphosphine ligands in the field of iron-catalyzed cross-coupling reactions is important for new applications in modern synthetic organic chemistry. This account summarizes the recent developments in practical and novel iron-catalyzed cross-coupling reactions employing bulky o-phenylene bisphosphine ligands and their mechanistic views.