609854-67-3Relevant academic research and scientific papers
Synthetic approach to 6-benzoyl-2H-[1,2,4] triazine-3,5-dione and 6-benzyl-5-thioxo-3,4-dihydro-2H-[1,2,4] triazin-3-one and studies on their transformation to fused [1,2,4]triazine systems
El Massry
, p. 1143 - 1155 (2003)
Reaction of phenylpyruvic acid with semicarbazide afforded 6-benzyl-2H-[1,2,4]triazine-3,5-dione (1) which upon oxidation with potassium dichromate furnished 6-benzoyl-2H-[1,2,4]triazine-3,5-dione (2) in good yield. Constructing pyrazolo[3,4-e][1,2,4] triazine system (4) was achieved by reacting 2 with arylhydrazines in ethanolic solution. However treatment of 2 with the less reactive heteroarylhydrazines gave only the corresponding hydrazones (3). Attempt for constructing 1,2,4,5,10-pentaaza-dibenzo[a,d]cyclohept-3-one (7) from 2 was failed and (benzoimidazol-2-yl) [1,2,4] triazine derivative (6) was the only product. Reaction of 1 with phosphorus pentasulphide afforded compounds 8 and 9. Compound 8 was transformed to the hydrazino compound 14, which led to the construction of triazolo[4,3-d] [1,2,4]triazine system. Thus compounds 15 and 16 were obtained by reacting 14 with carbon disulfide or acetic anhydride respectively. Attempt to couple 8 with chloroacetic acid failed, while it's known isomer 10 led to the formation of thiazolo [2,3-c] [1,2,4]triazine derivative (13). Simple theoretical calculation using AM1 and PM3 semiempirical Hamitonian provided rational ways to correlate the reactivity with structure proposed.
