A Novel and Facile Synthesis of Chroman‐4‐one Derivatives <i>via</i> Cascade Radical Cyclization Under Metal‐free Condition

Abstract

Abstract A novel and facile method for the synthesis of 3‐(2‐oxo‐2‐arylethyl)chroman‐4‐ones under metal‐free conditions is described. In the presence of n Bu 4 NBr and K 2 S 2 O 8 , arylaldehydes or aliphatic aldehydes with various functional groups could react with different 2‐(allyloxy)arylaldehydes via radical process to produce chroman‐4‐one derivatives in moderate to good yields. The method features metal‐free, step‐economical manner and easily available starting materials, exhibiting its practical synthetic value in some biologically active compounds.