Extending the range of pentasubstituted cyclopentadienyl compounds: The synthesis of a series of tetramethyl(alkyl or aryl)cyclopentadienes (Cp∗R), their iridium complexes and their catalytic activity for asymmetric transfer hydrogenation

The graphical abstract illustrates the approach to make Cp∗RIr(aa)Cl complexes using the specific example of the tetramethyl(isopropyl)cyclopentadiene system. The pictogram shows the synthesis of the cyclopentadiene ligand, then the mu-chloro iridium dimer, and then finally the prolinato complex.36