Aminodefluorination of 2-X-pentafluoro-1,4-naphthoquinones (X = NHnBu, NEt2, and OMe)

Aminodefluorination of 2-n-butylamino- and 2-diethylaminopentafluoro-1,4-naphthoquinone by alkylamines HNR1R2 (NR1R2 = NHEt, NHnBu and NEt2) occurs at the 6- or 8-position and further, accordingly, at the 8- or at one of the 5- and 6-sites. The isomer ratio changes significantly in favor of a β-replacement product with solvent variation in the sequence: toluene < 1,4-dioxane < DMSO. n-Butylaminodefluorination of 2-methoxypentafluoro-1,4-naphthoquinone gives mixtures of fluorine substitution products both on the benzene and quinone rings.