Iodine(III)‐Promoted Ring Contractive Cyanation of Exocyclic β‐Enaminones for the Synthesis of Cyanocyclopentanones

Abstract A highly efficient hypervalent iodine‐promoted regiocontrolled ring contractive cyanation (RCC) reaction of exocyclic β‐enaminones for the synthesis of cyanocyclopentanone (CCP) was demonstrated at ambient temperature with a wide substrate scope. The methodology offers a facile technique to construct an amino carbonitrile‐containing quaternary stereocenter at the α‐position of cyclopentanone in good yields. The sequence of substrate addition that can facilitate the reaction to follow different pathways (free radical/non‐radical) to afford the same final product was critically investigated. magnified image