The initial statistical model was trained on the observed selectivity (i.e., aggregate catalyst and background selectivity); however, subsequent kinetic studies highlighted the non-innocence of the background uncatalyzed reaction. We thus hypothesized that our initial model (Figure ) for the observed selectivity may have suffered from the competing processes. To better understand the interplay of the catalyst and substrate steric matching required for enantioinduction and determine which catalysts and/or substrates may be most impacted by higher background reactivity, we further analyzed the steric heatmap (Figure ). There is a clear optimal region (gray-shaded area). The catalyst active region excludes catalyst 3g, which contains the methyl-substituted phosphinate substituent. This observation can be explained by the fact that catalyst 3g exhibits higher conformational flexibility seen in cinchona-derived catalysts and is able to accommodate the substrate in various orientations (Figure ). The small methyl substituents are sterically less encumbered and allow for facile quinoline rotation in the catalyst, which leads to a faster reaction rate (green, Figure ). Additionally, collapse of (R)-enantiomer tetrahedral intermediates having the sulfonimidamide substituents pseudo-equatorially can be more readily accessed by catalyst 3g ((R)-14, Figure ), which leads to degraded selectivity. The behavior of catalysts 3k and 3h (light purple shaded area, Figure ) is similar to those in the optimal region. However, the significant perturbation of the quinoline group (3,5-(CF3)2C6H3) for catalyst 3k impacts the lowest ground state conformation of the catalyst (Figure ). To minimize the molecule's overall dipole, catalyst 3k prefers to have the quinoline positioned orthogonally to the catalysts in the optimal region, thus lowering the ground state by ~1.0 kcal/mol. As a result, the overall activation barrier to the tetrahedral adduct collapse is increased, and the uncatalyzed background reaction becomes more competitive (purple, Figure ). Catalyst 3h lies in some degree between catalysts 3g and 3k, as the er erosion is observed due to a combination of conformational flexibility, lower ground state energy, and slower rate (orange, Figure ).