Enantioselective hydrogenation Taniaphos

Table 41.13 Enantioselective hydrogenation of enamides catalyzed by Rh-Taniaphos in various ionic liquids/water combinations and in conventional solvents [104].

The screening of the different reaction media proved that the application of an ionic liquid/water mixture - a so-called wet ionic liquid - led to improved catalyst recycling compared to the reaction in ionic liquid without co-solvent. This comparative study revealed good results for the hydrogenation of various enamides in wet ionic liquids with respect to conversion, enantioselectivity and catalyst separation. The results obtained with the Rh-taniaphos system in different solvent systems are summarized in Table 5.3-4. 

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