Our previous mechanistic studies of the copper mediated transient C-H functionalization of aldehydes was indictive of a Wheland-like transition state for C-H activation. Here NBO analysis of TS-3/4 revealed a similar charge distribution to that of an arenium ion, in addition to a significant stabilizing effect from donation from the C-Cp system into empty orbitals on Cu. The similarities in geometry between TS-3/4 and an arenium ion also support C-H activation by a Wheland-like intermediate in the benzylamine functionalization. In summary, the catalytic C-H sulfonylation of benzylamines has been achieved using both catalytic copper acetate and a catalytic aldehyde transient directing group. Earth abundant and cheap manganese dioxide was used as a stoichiometric oxidant. The efficacy of this oxidative C-H coupling was demonstrated on a broad range of sulfinate salts and amines allowing rapid construction of g-sulfonyl amines. Mechanistic experiments and computational investigations indicate this reaction proceeds through a turnover limiting C-H activation step involving a Wheland type intermediate. A significant role of the TDG is to lower the barrier for C-H activation. We expect these findings to unlock further possibilities in the use of transient directing groups with copper catalysis.