Varying both parameters based on the accessible range of parameters of pump D did not increase the yield of 5 when using the fine magnesium turnings compared to synthesis using pulsation-free pump C. The selectivity decreased with increasing oscillatory Reynolds number (figure ). The highest selectivity was still achieved by oscillation-free flow conditions. A similar correlation was observed for the oscillation frequencies (figure ). The maximum selectivity thus shifts to smaller oscillatory Reynolds numbers in benzylmagnesium bromide synthesis. Evaluation of the effect of the stroke volume (see figure ) suggests that increasing the stroke volume above a value of 100 µL (maximum stroke volume for pump D with the used pump head, highest amplitude) could lead to an improved selectivity.