Synthesis of Novel Amino‐Acid‐Derived Sulfinamides and Their Evaluation as Ligands for the Enantioselective Transfer Hydrogenation of Ketones

Abstract

Novel chiral mono-sulfinyl diamines bearing a stereogenic sulfur atom were prepared in moderate to good yields starting from amino acids by means of a reductive amination of the corresponding amino aldehydes. Their potential as ligands for asymmetric catalysis was evaluated in the metalcatalyzed enantioselective transfer hydrogenation of alkyl-

Synthesis and Applications of tert-Butanesulfinamide

“…Adolfsson and co-workers investigated the use of amino-acid derived sulfinamide ligands of general structure 1228 (Figure ) in the enantioselective transfer hydrogenation of ketones . Ligand 1228a , bearing the N - tert -butanesulfinyl group, proved to be inferior to the analogous p -toluenesulfinyl ligand 1228b in the Rh-catalyzed transfer hydrogenation of acetophenone (Scheme ), providing the product alcohol 1230 with inferior conversion (18% vs 87%) and enantioselectivity (34% vs 43%).…”

Chiral Organosulfur Ligands/Catalysts with a Stereogenic Sulfur Atom: Applications in Asymmetric Synthesis

“…The catalytic reductions allowed for up to 77% conversion and led to the formation of chiral alcohols with up to 91% ee (Scheme 47). 102…”

Simple N-Sulfinyl-Based Chiral Sulfur–Olefin Ligands for Rhodium-Catalyzed Asymmetric 1,4-Additions

“…Very recently, Qin and co-workers reported the development of biaryl P , N -sulfinyl imine ligands 3a , b and their application in Pd-catalyzed asymmetric addition of arylboronic acids to N -benzylisatin . Moreover, some chiral ligands as well as organocatalysts possessing acidic N–H as binding element have also been developed . In these reported ligands, either nitrogen or oxygen acts as the coordination atom.…”