Abstract One-pot synthesis of 2-methylquinoxaline, 3-hydroxy-2-methylimidazo [1, 2-a] pyridine, and 2-methyl-3, 7-dihydroimidazo [1, 2-a] pyrazin-3-one via cycloaddition of N, N- binucleophilic o-phenylenediamine, 2-aminopyridine, and 2-aminopyrazine, respectively, to methylglyoxal generated in situ by hydrolysis of 2-alkoxypropenals is reported for the first time. Thus 2-alkoxypropenals in weakly acidic medium (25–80° C, 1–4 h) are convenient ...