Lewis Acid Catalyzed C-N Bond Formation: Synthesis of Quinoxalines via CuX (X = Cl, Br, I) Catalyzed Cyclotrimerization of Alkynes with o-Phenylendiamines
A novel way of synthesizing quinoxalines efficiently through cyclization of o-phenylenediamine and terminal alkyne by Cu(II) and bases is developed. This reaction proceeds smoothly to give the products in moderate to good yields.