Solid-state nickel(0)-mediated Yamamoto coupling enabled by mechanochemistry

Herein, we report the first solid-state protocol for nickel(0)-mediated Yamamoto-coupling reactions using ball milling. A variety of aryl halides reacted efficiently in the presence of bis(cyclooctadiene)nickel(0) [Ni(cod)2] and 4,4'-di-tert-butyl-2,2'-bipyridyl under solid-state mechanochemical conditions, affording the corresponding biaryls in high yields. Considering that potentially harmful and high-boiling organic solvents are not required, the present study provides a more convenient, environmentally friendly, and sustainable alternative to conventional solution-based Yamamoto coupling. Solid-state Yamamoto-coupling polymerization and the development of a catalytic variant are also described.