Sulfinate-Organocatalyzed (3+2) Annulation of Allenyl Sulfones with 1,1-Dicyano Olefins in the Presence of a Quaternary Ammonium Phase Transfer Agent

Abstract : The benzenesulfinate‐catalyzed (3+2) annulation between allenyl sulfones and aryl(alkyl)idenemalononitriles has been developed under mild phase transfer conditions, affording a breadth of functionalized sulfonyl cyclopentenes in good to excellent yields (22 examples, 49–99%) and high diastereoselectivities. These adducts were likely generated, via an allylsulfone anion featuring a quaternary ammonium cation.