Synthesis of Carborane-Fused Lactones via Electrochemical C(sp3)-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 ortho-disubstituted benzene bioisosteres, particularly fused-ring systems, remains underexplored. Herein, we report an electrooxidative protocol for the synthesis of carborane-fused lactones via C(sp3)-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.