Radical Reactions for the Synthesis of 3‐Substituted Chroman‐4‐ones

Radical cascade cyclizations of o-allyloxybenzaldehydes have emerged as a powerful strategy for the synthesis of 3-substituted chroman-4-ones. This minireview summarizes the incorporation of various functional groups into the C3-position of chroman-4-ones by employing appropriate radical precursors through transition-metal-free systems, silver-catalyzed systems, or visible-light-promoted systems.