FLUORINATIONS WITH COMPLEX METAL FLUORIDES PART 8. RING REARRANGEMENT IN THE FLUORINATIONS OF QUINOLINE WITH CAESIUM TETRAFLUOROCOBALTATE AND WITH COBALT(III) FLUORIDE

Article abstract of DOI:10.1016/S0022-1139(00)81454-2

Fluorination of quinoline by caesium tetrafluorocobaltate at ca. 350 deg C afforded mainly a mixture of pentadecafluoro-2-azabicyclo<4,4,0>dec-1(2)-ene (E), and heptadecafluoro-1-azabicyclo<5,3,0>decane (F), arising by skeletal rearrangement.Minor products were six polyfluorocyclohexapyridines (G-L) all with carbocyclic rings having the -(CF2)4 - moiety.Compound F was unreactive, but E was highly susceptible to nucleophiles, e.g. water and methanol.Isoquinoline was fluorinated similarly, but the only new product isolated was tridecafluoro-3-azabicyclo<4,4,0>deca-1(6)-2-diene (R).The rearrangement occurring with quinoline prompted a re-examination of its fluorination by cobalt(III) fluoride.At ca. 350 deg C, compound F was the major product, with very little E: there were some ring-opened materials, the most important being tetradecafluoro-4-pentafluoroethyl-2-azaoct-2(Z)-ene (N).