Elusive Antimony-Centered Radical Cations: Isolation, Characterization, Crystal Structures, and Reactivity Studies.

One-electron oxidation of the stibines Aryl Sb (1, Aryl=2,6- Pr -4-OMe-C H ; 2, Aryl=2,4,6- Pr -C H ) with AgSbF and NaBAryl (Aryl =3,5-(CF ) C H ) afforded the first structurally characterized examples of antimony-centered radical cations 1 [BAryl ] and 2 [BAryl ] . Their molecular and electronic structures were investigated by single-crystal X-ray diffraction, electron paramagnetic resonance spectroscopy (EPR) and UV/Vis absorption spectroscopy, in conjunction with theoretical calculations. Moreover, their reactivity was investigated. The reaction of 2 [BAryl ] and p-benzoquinone afforded a dinuclear antimony dication salt 3 [BAryl ] , which was characterized by NMR spectroscopy and X-ray diffraction analysis. The formation of the dication 3 further confirms that the isolated stibine radical cations are antimony-centered.