Electromagnetic Mill Promoted Mechanochemical Sonogashira Coupling Reaction and Mechanism Insight into the Catalytic Complex

Abstract A solid‐state Pd/Cu co‐catalyzed Sonogashira coupling facilitated by electromagnetic milling (EMM) was realized without solvent or additional heating. This strategy exhibited excellent substitutions tolerance and a wide substrate scope. The physical parameters were investigated, which proved both of magnetic field strength and frequency to be positive correlation to yields. Meanwhile, the suitable size of the grinding medium is key to the transformation. The coordination between copper, palladium and ligands were investigated by mass measurement and 31 P NMR, proving that CuI, PPh 3 , and DABCO coordinated in a 1:1:1 ratio under EMM, and DABCO could efficiently inhibit the homocoupling by‐product from alkyne. The active catalyst complex for the Sonogashira coupling reaction in EMM is generated in situ. The EMM system offers a straightforward method for Sonogashira coupling and demonstrates significant potential for practical applications.