Synthesis of Carborane-Fused Lactones via Electrochemical C( <i>sp</i> ³ )–H Lactonization: Access to Benzofused Lactone Bioisosteres

The replacement of the benzene ring with its bioisosteres is a powerful strategy in drug discovery, yet the development of <i>ortho</i>-disubstituted benzene bioisosteres, particularly fused-ring systems, remains underexplored. Herein, we report an electrooxidative protocol for the synthesis of carborane-fused lactones via C(<i>sp</i>³)-H lactonization. This protocol provides concise access to carborane-fused γ- and δ-lactone frameworks, which closely mimic the geometric features of benzofused lactones, thereby underscoring their potential as bioisosteres of benzofused lactones.