N-N Torsion Angle in BINAM-Mono and Bis(Sulfonamide) Ligands and its Effect on the Catalytic Asymmetric Transfer Hydrogenation (ATH) of Aromatic Ketones

Abstract

Ligands L1 and L2 were synthesized from commercially available (R)-(+)-1,1’-binaphthyl-2,2’-diamine and tested with RhIIICp* as catalysts in the asymmetric transfer hydrogenation of aromatic ketones in aqueous sodium formate. The results were compared with ligands derived from 1,2-, 1,4-, and 1,6-diamines, and correlated to the metal chelate ring size and the N-N torsion angles determined by theoretical calculations.