Highly efficient synthesis of quinoxaline derivatives from 1,2-benzenediamine and -aminoxylated 1,3-dicarbonyl compounds

Simple and efficient synthetic procedures for the preparation of quinoxaline, pyrazine, pyridopyrazine, and benzoxazin-2-one derivatives were developed. The one-pot cascade process involves the acidic elimination of -aminoxylated dicarbonyl compounds to generate 1,2,3-tricarbonyl compounds and subsequent condensation with 1,4-N,N or -N,O dinucleophiles to afford quinoxaline, pyrazine, pyridopyrazine, and benzoxazin-2-one scaffolds. All the proposed processes do not need extra catalysts, dry solvents, or harsh reaction conditions.