Nitroxide chemistry. Part V. Reactions between bistrifluoromethyl nitroxide and alkylbenzenes; mechanism of formation of carbonyl compounds

Abstract

The reaction sequence ArCH₃ [graphics omitted] XH + ArCH₂X [graphics omitted] XH, ArCHX₂, (CF₃)₂NX, ArCOX[Ar = Ph, p-ClC₆H₄, C₆F₅; X =(CF₃)₂N·O] has been established, and evidence adduced for the formation of aldehydes, ArCHO, as precursors of the carbonyl compounds ArCOX. The compounds PhCH₂X, PhCHX₂, and PhCX₃ have been synthesised by treatment of benzyl bromide, benzylidene dichloride, and benzylidyne trichloride, respectively, with the mercurial HgX₂[X =(CF₃)₂N·O]; the first of these undergoes C–O bond cleavage when heated with hydrobromic or hydriodic acid, with liberation of the hydroxylamine (CF₃)₂N·OH; the last decomposes thermally into PhCO₂N-(CF₃)₂ and two compounds believed to be isomers of (CF₃)₂N·C₆H₄·CO₂·N(CF₃)₂.