Diaryldichalcogenide radical cations

摘要

One-electron oxidation of two series of diaryldichalcogenides (C6F5E)(2) (13a-c) and (2,6-Mes(2)C(6)H(3)E)(2) (16a-c) was studied (E = S, Se, Te). The reaction of 13a and 13b with AsF5 and SbF5 gave rise to the formation of thermally unstable radical cations [(C6F5S)(2)](center dot+) (14a) and [(C6F5Se)(2)](center dot+) (14b) that were isolated as [Sb2F11](-) and [As2F11](-) salts, respectively. The reaction of 13c with AsF5 afforded only the product of a Te-C bond cleavage, namely the previously known dication [Te-4](2+) that was isolated as [AsF6](-) salt. The reaction of (2,6-Mes(2)C(6)H(3)E)(2) (16a-c) with [NO][SbF6] provided the corresponding radical cations [(2,6-Mes(2)C(6)H(3)E)(2)](center dot+) (17a-c; E = S, Se, Te) in the form of thermally stable [SbF6](-) salts in nearly quantitative yields. The electronic and structural properties of these radical cations were probed by X-ray diffraction analysis, EPR spectroscopy, and density functional theory calculations and other methods.