Half-Sandwich Rhodium(III), Iridium(III), and Ruthenium(II) Complexes with Ancillary Pyrazole-Based Ligands

Over the past decades, half-sandwich Ir(III), Rh(III), and Ru(II) complexes have received considerable attention due to their potential applications. This chapter will address historical background and recent developments on the coordination chemistry of half-sandwich derivatives of (arene)Ru(II), CpRu(II), CpRh(III) and CpIr(III) (Cp = cyclopentadienyl) with pyrazoles and pyrazole-based ligands and their potential applications. Synthetic methods and the structural and functional properties of the target complexes are discussed in detail.