Two isomers of 2-aryl-2H-[1,2,4]triazoloquinolin-3-one and 2-aryl-2H-[1,2,4]triazoloisoquinolin-3-one derivatives were synthesized by using α-chloroformylarylhydrazines hydrochloride with quinoline. The isomers were isolated and fully characterized by spectroscopic. Following the furthure X-ray crystallographic analysis, we supposed a plausible mechanism through N-substitution, ring opening, cyclization and dehydrogenation to provide the 2-aryl-2H-[1,2,4]triazoloisoquinolin-3-ones.
