Electrochemical assembly of isoxazoles via a four-component domino reaction.

Multicomponent domino reactions via electrochemical annulations have emerged as a robust strategy for the rapid assembly of heterocyclics. Herein, an electrochemical annulation via a [1 + 2 + 1 + 1] four-component domino reaction was accomplished in a user-friendly undivided cell setup to assemble valuable five-membered isoxazole motifs. Our approach is characterized by a high level functional group tolerance and operational simplicity, avoiding the tedious and time-consuming preparation of pre-functionalized substrates. Detailed mechanistic studies were conducted including isotopic labeling, kinetic studies, cyclic voltammetry (CV) analysis, and intermediate characterization, providing support for a radical pathway.