Synthesis of 2-aminopentafluoro-1,4-naphthoquinone derivatives

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

“…Quinones 3a-6a, 3b-6b and 8 display the F-3 singlet between d F À164.4 to À160.1 ppm which is up-field shifted compared with d F À157.2 ppm observed for 2a [1]. This is a natural consequence of the 6-and 8-alkylamine group conjugation with the 1-C5 5O group.…”

“…Quinone 1 with diethylamine (a 1:1.5 mole ratio, dioxane, room temperature) gave the F-2 replacement product 2b (reaction b in Scheme 2) [1], whereas with a threefold stoichiometric excess of the amine in DMSO at room temperature also the replacement of F-6 occurred to afford 2,6-bis-diethylaminotetrafluoro-1,4-naphthoquinone 3c in 43% yield. The latter result is similar to that described above for ethylamine (Scheme 2, reaction a).…”

Synthesis diphenyl(X)phosphonium betaines (X = CH3, C6H5, 2,5-F2C6H3) from hexafluoro-1,4-naphthoquinone

“…General synthetic route to the title compounds 4-6. Analogously to the earlier described synthesis of ammonium betaine 1, 4 one may believe that phosphonium salt A is originally formed, in which a triphenylphosphonium group activates effectively the neighboring position 3 for a nucleophilic attack, whereupon the rapid The interaction of naphthoquinone 3 with triphenylphosphine resulted in ~25% consumption of the starting material to give betaine 4 in 18% isolated yield (Scheme 2).…”

Cytotoxicity of new polyfluorinated 1,4-naphtoquinones with diverse substituents in the quinone moiety

“…Quinones 7 and 9 were prepared accordingly to reported methods. 17 6. A mixture of quinone 9 0.103 g (0.40 mmol), 2-mercaptoethanol 0.075 g (0.97 mmol) and methanol (5 ml) was stirred for 30 min at room temperature.…”

“…Quinones 1, 3-5, 7, and 8 were synthesized recently by amino-or methoxydefluorination of hexafluoro-1,4-naphthoquinone (10) with corresponding amines or MeOH. 17 Previously unknown compounds 2 and 6 were prepared via the reactions of 2-methoxy-3,5,6,7,8-pentafluoro-1,4-naphthoquinone or 2,5,6,7,8-pentafluoro-1,4-naphthoquinone 18 with MeOH or 2-mercaptoethanol, respectively (Scheme 1). Their structures were confirmed by 1 H and 19 F NMR spectra (in DMSO-d 6 or dry acetone-d 6 ), and elemental analysis.…”