An Organocatalysis Based Carbocyclic Spiroindoline Synthesis Enables Facile Structure-Activity Relationship (SAR) Study at C2 Position.

An asymmetric synthesis of carbocyclic spiroindoline by sequential Michael reaction and [3 + 2]-cycloaddition is described. This protocol demonstrates excellent enantio- and diastereoselectivity with broad functional group tolerance. A diverse range of spiroindolines were prepared by this approach, and the products served as ideal substrates for C2 derivatization.