Mixed-valence thiophosphorus compounds. Fluoro- and (trifluoromethyl)(thiophosphorylthio)phosphines with chiral phosphorus centers

Article abstract of DOI:10.1021/ic50189a024

Reactions of the acids (CF₃)₂PS₂H and F₂PS₂H with the fluoro(trifluoromethyl)aminophosphine CF₃(F)PN(CH₃)₂ and the reaction of the new acid F(CF₃)P(S)SH with the fluoro- or (trifluoromethyl)aminophosphines X₂PN(CH₃)₂ (X = F, CF₃) provide new isomeric (thiophosphorylthio)phosphines XYP(S)SPX′Y′ (X, Y, X′, Y′ = F, CF₃) with chiral phosphorus centers. The compounds were characterized chemically and by NMR spectroscopy. Geminal CF₃-CF₃ (9.0 Hz for CF₃ on pentavalent P; 7.2 Hz for CF₃ on trivalent P) and F-F (82.5 Hz for F on pentavalent P; 92.5 Hz for F on trivalent P) coupling constants are revealed in the NMR spectra of the molecules as a result of the presence of the chiral phosphorus centers. Directly bound geminal fluorine atoms on trivalent P show large chemical shift difference between the two fluorine atoms (4.4 ppm) accompanied by substantially different ¹J_PF coupling constants (1370 and 1291 Hz). Similar but smaller differences prevail between geminal CF₃ substituents. Reaction of the new acid F(CF₃)P(S)SH with CF₃(F)PN(CH₃)₂ gave a mixture of (thiophosphorylthio)phosphine isomers each with two chiral phosphorus centers. Only partial assignment of the major features of this spectrum could be made.