Copper-promoted direct sulfenylation of C1–H bonds in 4-aryl pyrrolo[1,2-a]quinoxalines†
Abstract
Methods for direct functionalization of C(sp2)–H bonds in pyrrolo[1,2-a]quinoxalines have witnessed emerging development over the last decade. Herein we report a new tactic to afford a selective sulfenylation of 4-aryl pyrrolo[1,2-a]quinoxalines with diaryl disulfides. The reactions proceeded in the presence of a copper catalyst and potassium iodide promoter. Functionalities including nitro, ester, amide, methylthio, and halogen groups were all tolerated. Our method offers a convenient route to obtain highly substituted pyrrolo[1,2-a]quinoxalines-based thioethers in moderate to good yields.