A facile synthesis of fluorine‐containing heterocycles ‐ use of 1,1,1‐trifluoro‐2‐alkanones as a convenient synthetic intermediate

1,1,1‐Trifluoro‐2,3‐alkanediones 2 easily obtainable from various aldehyde dialkylhydrazones were reacted with several diamines to afford trifluoromethylquinoxalines 3 and trifluoromethylpyrazines 4 in good yields. With the use of aldehydes and aqueous ammonia instead of diamines, diketones 2 were successfully converted to the corresponding 4‐trifluoromethylimidazoles 5 in satisfactory yields.