Oxidation of Carbene-Stabilized Diarsenic: Diarsene Dications and Diarsenic Radical Cations

Oxidation of carbene-stabilized diarsenic, L:As–As:L
[L:
= :C­{N­(2,6-iPr2C6H3)­CH}2] (1), with gallium chloride
in a 1:4 ratio in toluene affords the dicationic diarsene complex
[L:AsAs:L]2+([GaCl4]−)2 (22+[GaCl4]2), while oxidation of 1 with GaCl3 in a 1:2 ratio in Et2O yields the monocationic
diarsenic radical complex [L:AsAs:L]•+[GaCl4]− (2•+[GaCl4]). Strikingly, complex 2•+ is the first arsenic radical to be structurally
characterized in the solid state. The nature of the bonding in these
complexes was probed computationally and spectroscopically.