Regioselectivity Switch Achieved in the Palladium Catalyzed α-Arylation of Enones by Employing the Modified Kuwajima–Urabe Conditions
摘要:
A new regioselective approach to the synthesis of alpha-aryl enones is reported. This represents an important application of the Kuwajima-Urabe protocol toward the synthesis of this simple albeit complex functional array. Several a-aryl enones were synthesized by the palladium catalyzed arylation of triethylsilylenol ethers of enones with high regioselectivity and broad scope, utilizing sterically encumbered electron-rich phosphine ligands to drive the reaction.
approach has been developed for the synthesis of substituted 2-alkenyl-3-arylindoles. The strategy comprises palladium-catalyzed dual α-arylation of TES-enol ethers of enones as the key step. This methodology results in products with very good yields and the regioselectivity is exclusive. We have also successfully used this dual α-arylation methodology in the formal synthesis of the cholesterol-lowering drug
A new unified strategy has been developed for the synthesis of substituted 2-alkenylindoles and carbazoles. The strategy uses palladium-catalyzed alpha-arylation of TES-enol ethers of enones as the key step. The method is highly regioselective, provides good yields, and is expected to have wide application.