Thermal treatment of the successful sulfamated anilines (2) under reflux led to low to modest conversions of the sulfonated product (Chart 3). All structures where the para site was accessible afforded an isolable (3-24% yield) of the para-sulfonated product. The ortho accessible analogue (4c) did not form under these conditions despite similar electron rich electronics to 4b. Instead, under these conditions we were able to regenerate TBSAB and aniline, demonstrating the reversibility of this reagent for the first time. These results (4b, 4d, 4e, 4f) where both ortho sites are blocked agree with both the Illuminati and Spillane stepwise intermolecular mechanism -as an ortho-para sulfate walk is not possible. Due to the non-isolation of 2g (Chart 2), 4g could not be generated in a stepwise manner, we decided to react 2,6chloroaniline directly with TBSAB and reflux in a one-pot set-up, a low conversion 7% and 5% isolated yield of 4g was found suggesting challenging sterically demanding and electron withdrawing examples could be prepared in one-pot and may also improve other lower yielding examples. We thus screened one-pot conditions for the direct reaction of anilines with TBSAB and in situ thermal rearrangement (Chart 4).