Mechanochemical Difluorocarbene‐Mediated C(sp 3 )–N Bond Cleavage and In Situ Formylation of Tertiary Amines

C(sp 3 )–N bond cleavage is a pivotal transformation in organic synthesis. To the best of our knowledge, mechanochemical methods are unknown. Herein, we present a sustainable mechanochemical strategy in which a difluorocarbene precursor effects direct cleavage of tertiary amine C(sp 3 )–N bonds with concurrent in situ N ‐formylation. The approach overcomes limitations of conventional methods, exhibiting an excellent substrate scope and a broad functional group tolerance. Diverse aliphatic and heterocyclic amines are efficiently converted into N‐ formamides under mild ball‐milling conditions. The versatility of the method is validated by gram‐scale syntheses, subsequent molecular derivatizations, and syntheses of macrocyclic molecules. In addition, mechanochemical difluoromethylative ring‐openings of thioethers and ethers are described, highlighting potential applications in natural product syntheses and drug development.