The importance of 1,2-anti-disubstitution in monotosylated diamine ligands for ruthenium(II)-catalysed asymmetric transfer hydrogenation

The synthesis and applications to transfer hydrogenation of three derivatives of the popular TsDPEN are described. The results clearly demonstrate the importance of both disubstitution and the anti arrangement of substituents on this ligand. An explanation for the significance of these results is forwarded.