After establishing the optimized reaction conditions for batch, we wanted to find conditions for a flow procedure. It was observed that plastic parts made out of PEEK did not tolerate the acidic conditions in HFIP, and the solvent was changed back to TFE. This worked surprisingly well with only two equivalents of TfOH forming the product 1a in 74% yield (Table , entry 1). Unfortunately, it was found that these reaction conditions are not transferable to the proposed multi-step procedure due to the need of additional benzene which forms a black precipitate clogging the flow reactor. This could be overcome by employing MeNO2 as a solvent leading already to a 48% yield of 1a (Table , entry 2). The yield could be increased further by a combination with TFE to 63% (Table , entry 3). We could also omit the additional electrolyte TBABF4 with no product loss (Table , entry 4), while the yield could not be improved further by increasing the charge (Table , entry 5).