2‐Arylhydrazono‐3‐oxopropanals in heterocyclic synthesis: Synthesis of arylazopyrazole, arylazoisoxazole and dialkylpyridazine‐5,6‐dicarboxylate derivatives. New one‐step synthesis of arylazopyrimidines

A novel synthesis of arylpyrazole, isoxazole, dialkyl 1,6‐dihydropyridazine 5,6‐dicarboxylate derivatives and a new one‐step synthesis of azolopyrimidines under microwave‐assisted conditions are reported.