Visible-light-induced Fe-catalyzed divergent synthesis of polybromoalkanes

Abstract

Bromoalkanes are key structural motifs in bioactive molecules and synthetic intermediates. While atom transfer radical addition (ATRA) reactions using brominated alkanes, such as CBr₄ and CHBr₃, enable efficient synthesis of polybrominated alkanes from alkenes, strategies for divergent synthesis of various polybromoalkanes are underexplored. Herein, we report a visible-light-induced Fe-catalyzed atom transfer radical addition (ATRA)–reductive debromination cascade between alkenes and CBr₄, switchably affording 1,1,1,3-tetrabromoalkanes, 1,1,3-tribromoalkanes, or 1,3-dibromoalkanes by simply modulating reaction conditions. This strategy offers a versatile and efficient platform for the divergent synthesis of polybromoalkanes from readily available starting materials.