Redox reactions of small organic molecules using ball milling and piezoelectric materials

Over the past decade, photoredox catalysis has harnessed light energy to accelerate bond-forming reactions. We postulated that a complementary method for the redox-activation of small organic molecules in response to applied mechanical energy could be developed through the piezoelectric effect. Here, we report that agitation of piezoelectric materials via ball milling reduces aryl diazonium salts. This mechanoredox system can be applied to arylation and borylation reactions under mechanochemical conditions

Iridium(I)-Catalyzed C-H Borylation in Air by Using Mechanochemistry

Mechanochemistry has been applied for the first time to an iridium(I)-catalyzed C-H borylation reaction. By using either none or just a catalytic amount of a liquid, the mechanochemical C-H borylation of a series of heteroaromatic compounds proceeded in air to afford the corresponding arylboronates in good-to-excellent yields. A one-pot mechanochemical C-H borylation/Suzuki-Miyaura cross-coupling sequence for the direct synthesis of 2-aryl indole derivatives is also described. The present study constitutes an important milestone towards the development of industrially attractive solvent-free C-H bond functionalization processes in air

Solid-State Radical C-H Trifluoromethylation Reactions Using Ball Milling and Piezoelectric Materials

The application of piezoelectricity for the generation of trifluoromethyl (CF3) radicals is reported together with the development of a method for the mechanochemical C-H trifluoromethylation of aromatic compounds. As compared to conventional solution-based approaches, this mechanoredox C-H trifluoromethylation enables cleaner and more sustainable access to a wide range of trifluoromethylated N-heterocycles and peptides, which are important structural motifs in modern drug discovery. This study thus represents an important milestone for future applications of mechanoredox systems to medicinal and pharmaceutical science

Solid‐State Radical C−H Trifluoromethylation Reactions Using Ball Milling and Piezoelectric Materials

The application of piezoelectricity for the generation of trifluoromethyl (CF3) radicals is reported together with the development of a method for the mechanochemical C-H trifluoromethylation of aromatic compounds. As compared to conventional solution-based approaches, this mechanoredox C-H trifluoromethylation enables cleaner and more sustainable access to a wide range of trifluoromethylated N-heterocycles and peptides, which are important structural motifs in modern drug discovery. This study thus represents an important milestone for future applications of mechanoredox systems to medicinal and pharmaceutical science