Enantioselective Addition of Dimethylzinc to α-Keto Esters

Abstract

The readily available (+)-N-Benzyl-(S)-mandelamide catalyzes the enantioselective addition of dimethylzinc to α-keto esters to give α-methyl-α-hydroxy esters containing stereogenic quaternary centers with moderate to good yields (56-87%). A good enantioselectivity of the reaction is obtained for aryl and heteroaryl keto esters. For these substrates ee values of 75-90% are obtained. The enantioselectivity is somewhat lower for the substrates bearing an aliphatic chain.

organometallic reagents - asymmetric catalysis - addition reactions - α-keto esters - mandelamides

References

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11

The flask was opened and the solid reagent rapidly added.