The Direct Synthesis of Arylxenon Trifluoromethanesulfonates via electrophilic substitution

The reaction of xenonbis(trifluoroacetate) and trifluoromethanesulfonic acid (triflic acid) gave the new, highly reactive unsymmetrical xenon‐oxo species CF 3 COOXeOSO 2 CF 3 . Benzene derivates, containing electron withdrawing substituents such as ‐F, ‐CF 3 , ‐Cl or ‐NO 2 were electrophilic attacked by this intermediate to yield arylxenon trifluoromethanesulfonates. Via this one‐pot synthesis trifluoromethanesulfonates with the cations [Xe(2,4,6‐F 3 C 6 H 2 )] + , [Xe(2‐F‐5‐NO 2 C 6 H 3 )] + , [Xe(2‐F‐5‐CF 3 C 6 H 3 )] + and [Xe(3,5‐(CF 3 ) 2 C 6 H 3 )] + were prepared. All compounds were characterized by their NMR, mass, and vibrational spectra. Additionally, several new arylxenon trifluoromethanesulfonates were detected by 129 Xe‐NMR spectroscopy as products of the reaction of 1,3‐F 2 C 6 H 4 and further deactivated benzenes with xenontrifluoroacetate trifluoromethane sulfonate. Fluoro substituents in ortho position to xenon significantly increase the thermal stability of the arylxenon trifluoromethanesulfonates obtained. The molecular structure of [Xe(2,6‐F 2 C 6 H 3 )][OSO 2 CF 3 ] was determined by single crystal diffraction methods. The arylxenon unit is weakly coordinated by one oxygen atom of the CF 3 SO 3 anion. The salt crystallizes in the triclinic space group P 1 , a = 880.9(3) pm, b = 1093.9(5) pm, c = 1209.8(5) pm, α = 89.04(4)°, β = 74.23(3)°, γ = 86.03(3)°, Z = 4.