Cover Picture: Cooperative Transition-Metal and Chiral Brønsted Acid Catalysis: Enantioselective Hydrogenation of Imines To Form Amines (Angew. Chem. Int. Ed. 22/2011)



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Modern metal catalysis combined with organocatalysis mediated by a chiral Brønsted acid offers an attractive and environmentally favorable alternative to well-established asymmetric hydrogenations with catalysts based on precious metals. M. Beller and co-workers describe in their communication on page 5120 ff. how the key to success is the cooperative action of specific well-defined achiral iron complexes and chiral bulky phosphoric acid esters.