Heterocyclic polyfluoro-compounds. Part XXII. Synthesis of octafluoro-4,4′-azopyridine and tetrafluoro-4-(pentafluorophenylazo)pyridine

Abstract

Thermolysis of 4-azidotetrafluoropyridine in the presence of pentafluoroaniline yields tetrafluoro-4-(pentafluorophenylazo)pyridine and N-(pentafluorophenyl)-N′-(tetrafluoro-4-pyridyl)hydrazine; catalytic hydrogenation of the former product yields the latter, which decomposes into 4-aminotetrafluoropyridine, pentafluoroaniline, and the azo-compound at 160 °C in vacuo. Octafluoro-4,4′-azopyridine can be obtained by pyrolysis of 4-(dichloroamino)tetrafluoropyridine, prepared by treatment of 4-aminotetrafluoropyridine with t-butyl hypochlorite.