| Abstract: | The divinyldiarsene radical cations {(NHC)C(Ph)}As]2(GaCl4) (NHC=IPr: C{(NDipp)CH}2 3 ; SIPr: C{(NDipp)CH2}2 4 ; Dipp=2,6‐iPr2C6H3) and dications {(NHC)C(Ph)}As]2(GaCl4)2 (NHC=IPr 5 ; SIPr 6 ) are readily accessible as crystalline solids on sequential one‐electron oxidation of the corresponding divinyldiarsenes {(NHC)C(Ph)}As]2 (NHC=IPr 1 ; SIPr 2 ) with GaCl3. Compounds 3 – 6 have been characterized by X‐ray diffraction, cyclic voltammetry, EPR/NMR spectroscopy, and UV/vis absorption spectroscopy as well as DFT calculations. The sequential removal of one electron from the HOMO, that is mainly the As?As π‐bond, of 1 and 2 leads to successive elongation of the As=As bond and contraction of the C?As bonds from 1 / 2 → 3 / 4 → 5 / 6 . The UV/vis spectrum of 3 and 4 each exhibits a strong absorption in the visible region associated with SOMO‐related transitions. The EPR spectrum of 3 and 4 each shows a broadened septet owing to coupling of the unpaired electron with two 75As (I=3/2) nuclei. |
