We have also identified the tertiary amine-containing heteroaromatic rings as a suitable class of substrates (28-31). Various N-benzyl/alkyl thienopyridines containing susceptible functional groups such as ester and allyl were tested. The reaction of 28 with benzonitrile 2 under DC electrolysis provided poor yield and selectivity for arylation product 28a relative to cyanation product 28b. In contrast, the yield of 28a improved from 17 % to 54 % under AC Figure . Substrate scope and product selectivity comparison between AC and DC electrolysis. Note: 18b and 19b were characterized using high-resolution mass spectrometry. Yields of 30a and 30b were determined using 1 H-NMR of the purified inseparable compounds. Regioisomers of 38a were formed in 1:0.6 ratio. The experimental voltage and frequency for each substrate are provided in the SI. conditions. Notably, the arylation occurred regioselectively at cyclic amine and the benzylic methylene group remained intact. In the presence of ester (29), DC electrolysis did not yield any products. This situation was altered when AC was applied, delivering both products at yield of 31% for 29a and 37% for 29b. In the case of N-allyl group, significant enhancement in yield and selectivity was not observed (30a and 30b). For late-stage functionalization of antiplatelet drug Ticlopidine 31, the arylation and cyanation product yields (31a and 31b) slightly increased under AC electrolysis.