Chiral 1,1′-Diphosphetanylferrocenes: New Ligands for Asymmetric Catalytic Hydrogenation of Itaconate Derivatives

The useful combination of high catalytic activity and high enantioselectivity is provided by rhodium catalysts based on a new class of FerroTANE ligands when employed in the hydrogenation of itaconate derivatives (see scheme). Reactions performed at S/C ratio of 20 000 are complete within 3 h and directly afford valuable 2-alkylsuccinamide products in up to 99 % enantiomeric excess.