Reductive Coupling of Acrylamides and Carbonyls via Solvated Electrons from Excited State Acridyl Radicals.

The reductive coupling of carbonyls and alkenes is primarily promoted by super stoichiometric quantities of samarium diiodide (SmI2). This reductant requires fresh preparation under moisture-free anaerobic conditions for successful reactivity. Herein, we describe a new method for reductive coupling of acrylamides with unactivated ketones and aldehydes by employing acridine radicals as excited state reductants. Ultrafast transient absorption spectroscopy experiments provided a clearer picture of the excited state acridine radical and its mechanism of action, which likely proceeds via the formation of solvated electrons in acetonitrile.