Haloferrocenes: Syntheses and Selected Reactions

Although haloferrocenes constitute important starting materials for many ferrocene-derived products with importance in a variety of fields such as materials science, medicinal chemistry and catalysis, only relatively few haloferrocenes out of the large number of possible examples have been prepared so far. The first part of this review summarizes the syntheses of all the homo- and heterohaloferrocenes known up to date. The second part summarizes typical reactions of haloferrocenes, namely lithiation followed by trapping with an electrophile, copper-mediated halogen substitution, coupling with formation of diferrocenyl derivatives, ortho-lithiation followed by trapping with an electrophile, palladium-catalyzed coupling reactions and finally miscellaneous reactions. 1 Introduction 2 Homohaloferrocenes 2.1 Fluoroferrocenes 2.2 Chloroferrocenes 2.3 Bromoferrocenes 2.4 Iodoferrocenes 3 Heterohaloferrocenes 4 Selected Reactions of Haloferrocenes 4.1 Lithiation Followed by Trapping with an Electrophile 4.2 Copper-Mediated Halogen Substitution 4.3 Coupling with Formation of Diferrocenyl Derivatives 4.4 ortho-Lithiation of Haloferrocenes 4.5 Palladium-Catalyzed Reactions of Haloferrocenes 4.6 Miscellaneous Reactions of Haloferrocenes 5 Conclusions