Palladium‐Catalyzed Asymmetric Construction of Vicinal All‐Carbon Quaternary Stereocenters and its Application to the Synthesis of Cyclotryptamine Alkaloids

A twofold Pd-DAAA Pd-catalyzed decarboxylative allylic alkylation (see scheme) was used to construct two vicinal all-carbon quaternary stereocenters (marked in red) in a diastereo- and enantioselective fashion. The products of the Pd-DAAA were further elaborated to complete the formal syntheses of cyclotryptamine alkaloids. The twofold Pd-catalyzed transformation proceeds through an initial matched allylation followed by a second mismatched allylation to deliver the desired product.