A palladium-catalyzed coupling of 3-chloroquinoxalinones with various nitrogen-containing nucleophiles

An efficient and general palladium-catalyzed coupling of 3-chloro-quinoxalinones with a variety of nitrogen-containing nucleophiles such as (hetero)aromatic and aliphatic amides as well as some challenging weakly nucleophilic nitrogen compounds including lactams, carbamates and NH-containing azoles is described. In all cases, the reactions take place rapidly and cleanly in dioxane using Pd(OAc)₂ as a catalyst, Xantphos as a ligand and K₂CO₃ as a base furnishing the coupling 3-N-substituted quinoxalinone products in good to excellent yields.