Ruthenium(ii)-catalyzed selective C-H bond activation of imidamides and coupling with sulfoxonium ylides: an efficient approach for the synthesis of highly functional 3-ketoindoles

Ruthenium-catalyzed selective C-H bond activation of imidamides and annulation of sulfoxonium ylides were achieved, which afforded a series of 3-ketoindole derivatives in good yields, with good functional group compatibility. The catalytic system generated an indole scaffold by C-N and C-S bond cleavage. This reaction constitutes the first intermolecular coupling of ylides with arenes to afford a 3-ketoindole skeleton by ruthenium-catalyzed C-H activation and annulation cascade.