One-pot synthesis of 1- and 2-substituted naphtho[2,3-d][1,2,3]triazole-4,9-diones.

A one-pot three-component [2+3] cycloaddition for the synthesis of 1-alkyl 1H-naphtho[2,3-d][1,2,3]triazole-4,9-dione and 2-alkyl 2H-naphtho[2,3-d][1,2,3]triazole-4,9-dione has been developed. By taking the advantage of difference in basicity, both products can be obtained in good purity. The unique heterocyclic scaffolds of these two products could exert interesting chemical and biological properties. The synthetic protocol is concise and suitable for scale-up synthesis of the desired products.