In previous studies, leaving groups are usually essential when applying EDA complexes to synthesis practice, and the reactions often required stoichiometric amounts of both electron donors and acceptors. Methyl viologen, which is known as an antimicrobial agent and herbicide, offers a promising alternative to generate EDA complexes and improve atom economy by avoiding the use of leaving groups. It was found to have three thermodynamically stable oxidation states (Scheme 2). These three oxidation states are the di-cation MV , radical cation MV •+ , and neutral methyl viologen MV. The MV 2+ can be reduced to the radical cation state MV •+ , and the reduction potential of MV 2+ to MV •+ is more feasible, which reveals the capability of being a single electron-acceptor. Furthermore, previous studies have also demonstrated that methyl viologen can act as an electron acceptor for many substrate classes to form EDA complexes, but, to the best of our knowledge, synthetic protocols have not been demonstrated. Scheme 2. Three oxidation states of methyl viologen.