Reactions associated with arene replacement in bis-(arene) iron complexes

Iron is one of the most abundant elements on the Earth and its chemistry has been therefore rapidly developed. As a part of the chemistry these complexes, a short review on the synthesis of bis-(arene) iron complexes and reactions associated with direct and indirect replacement of arene ligands in these complexes is presented. These reactions lead to a broad variety of novel iron sandwich compounds that now play an important role in the development of specific areas of metaloorganic and metallacarborane chemistry of iron. The review comprises recent synthetic routes and approaches to iron sandwich complexes, of which the most significant have been arene and cyclohexadienyl ferradicarba- and ferratricarba-boranes, together with new types of piano-stool structured compounds. The reader will also find references to methods of structural characterization of individual compounds in this area of chemistry.