Spirooxindoles: Synthesis via Organocatalytic Processes

Spirooxindoles are the privileged structural scaffolds frequently found in many natural products and pharmaceutical molecules. The rapid development of various organocatalytic activation modes and chiral organocatalysts enormously aroused the enthusiasm on the exploration of efficient and novel reactions for the diverse synthesis of high value-added chiral spirooxindoles via organocatalytic processes. A variety of reactions have been established well the design of new asymmetric domino reactions by enamine and iminium catalysis turned out to be a fruitful tactic for the construction of chiral spirocyclic complex molecules from simple starting materials. Chiral nucleophilic catalysis with chiral tertiary phosphines or amines has been widely applied in a variety of organic asymmetric reactions. With the rapid development of chiral N-heterocyclic carbene (NHC) catalysis in organic synthesis over the past few decades, the use of chiral NHC catalysis for the enantioselective assembly of spirooxindoles has gained much attention.