Asymmetric nitrile-hydration with bifunctional ruthenium catalysts bearing chiral N-sulfonyldiamine ligands

The asymmetric hydration of alpha-benzyl-alpha-methylmalononitrile was examined by using chiral bifunctional catalysts. Enantiomer discrimination of the prochiral dinitrile in the presence of water was demonstrated with a well-defined bifunctional amido-Ru complex having N-sulfonyldiamine ligands, and providing the corresponding amidato(amine) complexes diastereoselectively. Under the catalytic conditions, the (R)-cyanoamide was successfully obtained without further hydrolysis to carboxylic acids. (C) 2010 Elsevier Ltd. All rights reserved.