KHMDS Enhanced SmI2-Mediated Reformatsky Type α-Cyanation

A novel combination of SmI2, KHMDS, and TsCN can be utilized to introduce a cyano group into structurally diverse and highly sensitive 2-alkyl-chroman-4-ones. Subsequent oxidation allows the formed 2-alkyl-3-cyanochromones to be isolated in yields ranging from 49 to 77%. In addition, α-bromoketones and esters were found to undergo equally effective α-cyanation.