Fluorine containing heterocyclic compounds: synthesis of 6-substituted-2-substituted-aryl-1,2,4-triazolo[5,1-b] 1,3,5-thiadiazin-7-one derivatives

A group of heterocylic compounds of condensed triazole-thiadiazinone derivatives containing fluorine (IIIa–h) were obtained in good yields by the reactions of the corresponding 3-aryl-5-mercapto-1,2,4-triazole (IIa–d) with N-substituted-N-chloromethyl carbamoyl chloride (I) in the presence of potassium carbonate in N,N-dimethylformamide at room temperature. Cyclization of 3-(2,3,5-trifluoro-4-methoxyl)phenyl-5-mercapto-1,2,4-triazole (IIe) with I was difficult due to an intermolecular hydrogen bond of IIe. The structures of the compounds synthesized were confirmed by IR, MS, 1H NMR and elemental analyses. Fungicidal and insecticidal activities of these compounds were also studied.