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Over the last several years, chemists and engineers have identified the utility of using twin-screw extruders for performing large-scale organic chemistry mechanochemically. This equipment is convenient as it is familiar to several relevant industries for its use in formulation, and it is also well-equipped for temperature control and intense grinding of materials. However, the research and development scale of mechanochemistry is just like that of conventional synthesis: milligrams. These milligram-scale reactions are performed in batch-type reactors, often a ball mill. Commercially available ball mills do not have strict temperature control, limiting the information that can be obtained to inform the scale-up process reliably. This work uses an in-house modified, temperature-controlled, ball mill to bridge the knowledge gap regarding predictable, well-informed, economical, and reliable mechanochemical scale-ups. Included in this work is the first extrusion example of a nucleophilic aromatic substitution. 

Solvent-free mechanochemical conditions have been developed to investigate the significance of ion pairing and the use of weak bases for driving forward nucleophilic substitution reactions. This approach takes advantage of the lack of solvent shells to incorporate weaker and safer bases to drive reactions to completion through specific ion pairing pathways. The most efficient reactions contained larger and more polarizable cation and anion pairs.