Recently, we published the RegioSQM20 method, 6 which predicts the regioselectivities of EAS reactions from semiempirical calculations of proton affinities. The single-tautomer version of this method is applied to the 21,896 reactions to get proton affinities for all of the unique reaction sites. An extension of this method is also applied in which the Re-gioSQM20 calculations are followed by single point density functional theory (DFT) calculations in methanol (MeOH, dielectric = 33.6) using the PBEh-3c composite electronic structure method 15 and the conductor-like polarizable continuum model (C-PCM) as implemented in the quantum chemistry program ORCA version 4.2. 18 A few of the calculations resulted in extreme proton affinities corresponding to outliers in the dataset that complicated the development of regression models. However, the calculated proton affinities for both the original and extended RegioSQM20 calculations follow a Gaussian distribution (see supporting information), which enables the use of Chauvenet's criterion to remove these outliers in the dataset. In the Chauvenet's criterion the probability of the farthest point is calculated under the assumption of a Gaussian distribution. If this point is below some predefined value then the point is removed, and the procedure is repeated until no more points are removed. In our dataset molecules are removed if at least one atom in the molecule has a proton affinity corresponding to a probability below 1 %.