Diversified Synthesis of All-Carbon Quaternary gem -Difluorinated Cyclopropanes via Copper-Catalyzed Cross-Coupling.

The construction of all-carbon quaternary centers in small-ring systems is important but challenging in organic synthesis. Herein, by taking gem -difluorocyclopropyl bromides (DFCBs) as a type of general and versatile building block, we developed a practical method for building all-carbon quaternary centers in gem -difluorinated cyclopropanes (DFCs). The reaction relies on the involvement of a gem -difluorocyclopropyl radical intermediate, which can couple with a wide range of nucleophiles under copper catalysis.