Our investigation commenced with an exploration of the feasibility of SOF2 generation by flowing a solution of SOCl2 in CH3CN through a packed bed reactor filled with a 1:1 mixture of KF and glass beads (see the Supporting Information (SI) for details). We observed efficient and consistent formation of the coveted gaseous reagent regardless of the residence time of the solution within the packed bed reactor. Interestingly, the reactor cartridge itself has a reduced lifespan when decreasing residence time of the solution within it (see the SI for details). We reasoned that higher flow rates might lead to the formation of preferred flow channels, which prevent SOCl2 from reacting with the remaining KF present in the packed bed reactor. Subsequently, we coupled the thionyl fluoride generator to a stream of CH3CN solution containing a mixture of model substrate 4-phenylbenzoic acid 1 and Et3N and studied the influence of the stoichiometry and the flow rates of the different feeding solutions (Table ). This process demonstrated exceptional efficiency, as the acyl fluoride formation occurred in high yields when employing 4, 2, and 1.1 equivalents of thionyl chloride with respect to the carboxylic acid (entries 1-3).