Asymmetric Hydrogenation of Simple Enamides

Like reactions of many other prochiral olefins, the geometry of the enamine can affect selectivity. Thus, cyclic enamides that contain one geometry react with high selectivities (Equation 15.36). Alternatively, catalysts that react with both isomers with high selectivity for the same enantiomer can be developed. Equation 15.37 shows that the rhodium-DuanPhos complex catalyzes the hydrogenation of an /Z mixture of isomeric enamides with high enantioselectivity.  

Catalyst R Geometry Reaction conditions Percent ee of product (configuration) 

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