This work describes efficient EC and iPEC methods for the transformation of thioamides. The EC approach is inexpensive, mild, and metal- and catalyst-free. On the other hand, the interfacial iPEC method, due to the lower applied potential, proved to be beneficial in terms of broadening the scope and limitations and energy efficiency.

Abstract

Pursuing innovative and environmentally friendly synthetic strategies is always a desirable goal in organic synthesis, and thus, we have developed green and sustainable electrochemical (EC) and photoelectrochemical (iPEC) transformations of thioamides into amides. The established EC protocol is inexpensive, mild, and metal- and catalyst-free. iPEC cells are extensively studied for solar energy conversion, but their application in synthesizing high-value organic molecules has been limited. Here, we describe a strategy to use BiVO₄, an abundant and robust photoanode, for the desulfurization of thioamides. Under light irradiation, the photogenerated holes in BiVO₄ oxidize thioamides to radical cations, which further react with the oxygen radical anion to produce amides. The proposed iPEC strategy presents a high promise for green organic chemical transformations with the goal of maximizing not only the atom economy but also the energy efficiency.