Having established rAP as a unique chemoselective electroreduction tool, dearomative arene reduction was pursued as another synthetically useful electroreduction that was in need of a highly chemoselective variant. Although Birch reduction has been extensively utilized, the reaction requires harsh reductants such as alkaline metals in liquid ammonia, in which few synthetically useful functional groups could survive. Heteroarene reduction is even more challenging, and the lack of chemoselectivity of the process is evident in the reduction of methyl 2-thiophenecarboxylate 14 (Figure ). It is previously reported that Birch reduction of thiophenecarboxylic acid poses an issue of ring fragmentation, and the ester functionality could cause competing reduction. Indeed, various Birch conditions including conventional (entry 1), state-of-the-art (entry 2) 18 as well as electrochemical (entry 4) 19 led to extensive decomposition of 14 (Entres 1-2). The only workable case was a chemoselective variant employing lithium di-t-butylbiphenyl (LiDBB, entry 3). However, it lacks practicality as it requires 4 equivalents of a high molecular weight air-sensitive reductant that is actually more expensive than 14 itself. While simple DC electrolysis in protic solvent (THF/EtOH mixture, entry 5) led to mostly decomposition, switching to rAP under the same conditions resulted in strikingly clean formation of dihydrothiophene 15. Comparison of the crude 1 H NMR between DC and rAP vividly illustrates the profound impact of waveforms applied.