Inert‐Liquid Suspension‐Assisted Dosing of Solid Reagents for Automated Microscale Synthesis and High‐Throughput Experimentation

Accurate dosing of milligram‐ and sub‐milligram‐scale quantities of solid reagents remains a major challenge in automated high‐throughput experimentation (HTE). Here, we describe an inert‐liquid suspension‐assisted strategy in which solids are dispersed under stirring to form quasihomogeneous suspensions that can be transferred using standard liquid‐handling tools. The success of the method depends on two key operational features: in situ stirring during aspiration, which suppresses particle settling during pipetting, and prolonged prestirring, which improves suspension stability, likely by breaking down larger particles or weak aggregates. Useful performance was obtained for a broad range of inorganic salts, catalysts, ligands, boronic acids, and other organic solids when an appropriate solvent was selected. The method was further applied to automated amidation and microscale reaction‐condition optimization, demonstrating its practical value for handling poorly soluble solids in automated synthesis. Overall, this work provides a simple, low‐cost, and automation‐compatible approach for solid reagent dosing in HTE.