Direct di- and triamination of polyfluoropyridines in anhydrous ammonia

Aminodefluorination of polyfluoropyridines (pentafluoro-, 3,5-dichlorotrifluoro-, 3- and 4-chlorotetrafluoro-, 2,3,5,6- and 2,3,4,6-tetrafluoro-, 3-chloro-2,4,6-trifluoro-, and 2,4,6-trifluoropyridine) in anhydrous ammonia has been investigated. Temperatures of the second and third amino group introduction into pyridine ring were shown to increase significantly thus ensuring conditions for selective preparation of mono-, di- and, in the case of perhalopyridines as starting compounds, triaminoderivatives with high yield and purity.