Bis(catecholato)silanes were showcased as strong Lewis acids, while their inherent redox activity remained unexplored in this context. In the present work, we study the oxidation of monomeric bis(3,6-di-tert-butyl-catecholato)silane (1), leading to the Lewis superacidic radicalic silylium ionradical 1˙+ (FIA 784 kJ mol^(-1)). Oxidation of 1 with [N(p-C(6)H(4)Br)(3)][B(C(6)F(5))(4)] yielded [1][B(C(6)F(5))(4)], displaying strong catalytic activity in the Friedel-Crafts-dimerization,… …