Mo(0)-Catalyzed Allylic Alkylation of 3-Alkyloxindole

Significance

In the presence of a Mo(0)/Trost-type ligand system, allyl carbonate can be used to allylate the prochiral nucleophile 3-alkyloxindole to generate a quaternary stereocenter with moderate to excellent enantioselectivity and in excellent yields. While enantioselective Mo-catalyzed processes have been known for some time, this is the first example of a Mo-catalyzed enantioselective allylation of a prochiral nucleophile. A simple formal total synthesis of (-)-physostigmine is also reported.