A Continuous-Flow Electrochemical Taylor Vortex Reactor: A Laboratory-Scale High-Throughput Flow Reactor with Enhanced Mixing for Scalable Electrosynthesis

We report the development of a small footprint continuous electrochemical Taylor vortex reactor capable of processing kilogram quantities of material per day. This report builds upon our previous development of a scalable photochemical Taylor vortex reactor (Org. Process Res. Dev. 2017, 21, 1042; 2020, 24, 201-206). It describes a static and rotating electrode system that allows for enhanced mixing within the annular gap between the electrodes. We demonstrate that the size of the annular gap and the rotation speed of the electrode are important for both conversion of the substrate and selectivity of the product exemplified using the methoxylation of N-formylpyrrolidine. The employment of a cooling jacket was necessary for scaling the reaction in order to manage the heat generated by electrodes at higher currents (up to 30 A, >270 mA cm-2) allowing multimole productivity per day of methoxylation product to be achieved. The electrochemical oxidation of thioanisole was also studied, and it was demonstrated that the reactor has the performance to produce up to 400 g day-1 of either of the corresponding sulfoxide or sulfone while maintaining a very high reaction selectivity (>97%) to the desired product. This development completes a suite of vortex reactor designs that can be used for photo-, thermal-, or electrochemistry, all of which decouple residence time from mixing. This opens up the possibility of performing continuous multistep reactions at scale with flexibility in optimizing processes.