New C2-symmetric bis(sulfonamide)-cyclohexane-1,2-diamine-RhCp∗ complex and its application in the asymmetric transfer hydrogenation (ATH) of ketones in water

C2-symmetric bis(sulfonamide) ligands derived from trans-(1R,2R)-cyclohexane-1,2-diamine were synthesized and complexed with [Cp∗RhCl2]2 in situ and used in the ATH of aromatic ketones with aqueous sodium formate as the hydrogen source. The chiral secondary alcohols were obtained with 90-99% enantioselectivity and in 50-100% yield. Reductions in water were faster than those in isopropanol/KOH.