Iridium-, Copper- and Iron-Catalyzed Direct Arylations

Iridium-, Copper- and Iron-Catalyzed Direct Arylations 

Thus far, palladium-, rhodium- or ruthenium-based complexes have been predominantly employed for catalytic direct arylations. However, promising 

Various methodologies for catalytic direct arylations via C—H bond activation employing transition metals other than palladium have been developed in recent years. In particular, rhodium- and ruthenium-based complexes have enabled the development of promising protocols for catalytic direct arylations. Whilst rhodium catalysts were found broadly applicable to the direct aryiation of both arenes, as well as heteroarenes, ruthenium-catalyzed chelation-assisted C—H bond function-ahzations could be used for the conversion of a variety of attractive organic electrophiles. In addition, inexpensive copper and iron salts have recently been shown as economically attractive alternatives to previously developed more expensive catalysts. Given the economically and environmentally benign features of selective C—H bond functionalizations, the development of further valuable protocols is expected in this rapidly evolving research area. 

2 de Meijere, A. and Diederich, F. (eds) (2004) Metal-Catalyzed Cross-Coupling Reactions, Wiley-VCH Verlag GmbH, Weinheim. 

15 Wilkinson s complex was reported to catalyze hydro-dehalogenation reactions. See Petterson, A.A. and McNeill, K. (2006) OrganometaUics, 25, 

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