Synthesis of 1,2,4-triazine-3,5(2H,4H)-diones containing electronegative substituents in position 6

Abstract

Reaction of fluorine with 1,2,4-triazine-3,5(2H,4H)-dione (I) in acetic acid afforded the 6-fluoro derivative II in low yield. The 6-nitro compound III was prepared by oxidation of the 6-amino derivative of compound I with hydrogen peroxide in trifluoroacetic acid. Synthesis of the 6-cyano compound IV was accomplished by treatment of the 6-bromo derivative with cuprous cyanide in N,N,N',N'-tetramethylurea. The effect of substituents on the carbonyl frequencies for 6-substituted derivatives of I was studied.