1 Department of Chemistry and Biochemistry, Concordia University, Montreal, Canada. dr.x@concordia.ca.
2 Department of Chemistry, McGill University, Montreal, Canada.
3 Genentech, Inc., One DNA Way, South San Francisco, CA 94080, USA.
4 School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK. t.friscic@bham.ac.uk.

Resonant acoustic mixing (RAM) enables mechanoredox catalysis with BaTiO₃ as the piezoelectric catalyst on model diazonium coupling reactions. RAM proceeds without formal grinding or impact media, is faster than the analogous ball-milling strategy, and is readily scalable. X-ray diffraction and spectroscopy indicate that reusability of BaTiO₃ as a mechanoredox catalyst under ball-milling or RAM might be limited by boration.