Studies in azide chemistry. Part VI. Some reactions of perfluoroazidobenzene and perfluoro-4-azidotoluene

Abstract

Perfluoroazidobenzene readily undergoes the Staudinger reaction with triphenylphosphine, reacts with dimethyl sulphoxide at elevated temperatures to yield a sulphoximide, partakes in 1,3-dipolar cycloaddition reactions with diphenylacetylene, phenylacetylene, cyclopentadiene dimer, norbornene, and acrylonitrile, and, at 130 °C or above, gives the C–H ‘nitrene insertion’ product C₆F₅·NHPh with benzene, and, inter alia, the N–H ‘nitrene insertion’ products C₆F₅·N:NPh, C₆F₅·N:N·C₆H₄F-p, and C₆F₅·N:N·C₆F₅ with aniline, p-fluoroaniline, and pentafluoroaniline, respectively.

Perfluoro-4-azidotoluene reacts with dimethyl sulphoxide, cyclohexane, aniline, and pentafluoroaniline at 160 °C to yield Ar_FN:S(:O)Me₂, Ar_FNH·C₆H₁₁, Ar_FN:NPh + anilino-substituted derivatives, and Ar_FN:N·C₆F₅, respectively (Ar_F=p-F₃C·C₆F₄).

The nitrenoid N–H ‘insertion’ reactions provide a new method for the synthesis of unsymmetrical polyfluorinated aromatic azo-compounds.