The Application of New Chiral Ferrocene Ligands in Asymmetric Transfer Hydrogenation of Ketones

Four easily available ferrocenyl chiral ligands have been screened firstly for ruthenium (II)-catalyzed asymmetric transfer hydrogenation of acetophenone with HCOOH/Et3N azeotrope as the hydrogen source. A moderate chemical yield of 1-phenylethanol with 83% ee was obtained when (RC, SFc)-1-(Diphe-nylphosphino)-2-[1-N-(3-methylpyridin-2-ylmethyl) ethyl] ferrocene (L1) was used. Particularly, both ruthenium and iridium could coordinate with L1 to accomplish the asymmetric reduction of series of aromatic ketones separately. The desired products were achieved with up to 86% ee.<