After observing the mechanistic generality of catalyst 1d for both the SNAr and SN2 cyclizations, our initial intuition was to rationalize it with the geometric and stereoelectronic similarities of the two transition state structures. Therefore, the key non-covalent interaction set for each favored transition state would be comparable in type and magnitude and would perhaps favor the same enantiomer of each of the two classes of products despite the mechanistic differences. Instead, surprisingly, both computational modeling and X-Ray crystallographic analysis of enantioenriched products 3d and 5a pointed towards an enantiodivergence between the two ring sizes. While DFT modeling depicted the SN2 reaction as concerted, the SNAr appeared to be a stepwise process in the potential energy surface, and the Meisenheimer complex was characterized as a local minimum. However, subsequent fluoride elimination appeared barrierless (see Table -3 for energetic data). Regardless of the nature of the intermediate and the concertedness of the two elementary steps , we designate the addition transition state (TS 1 ) as both the rate-and enantiodetermining step for the SNAr. The modeling described a transition state assembly governed by several factors, the most evident being squaramide hydrogen bonding interactions with the substrate deprotonated sulfonamide. In addition, we noted some degree of global dipole minimization of catalyst and substrate, reflecting accumulation of negative charge in the proximity of the positively charged iminophosphorane group. In other words, the local dipoles of the catalyst and substrate, respectively, appear opposed in an overall dipole-minimizing complementary sense. However, while the dipole minimization heuristic seems effective at describing the relative orientation of catalyst and substrate in the transition state assembly, we do not believe that enantioselectivity (and enantiodivergence) is a consequence of a superior dipole minimization by one enantiomer of the substrate in the favored transition state. In fact, the magnitude of the transition state dipole does not correlate with the relative stability of the transition states. Additionally, the differential solvation free energy term (ΔΔGsolv), when significant, favors the minor enantiomer. On the other hand, non-local Van der Waals dispersion energy (evaluated though the VV10 (36) functional, as a component of the ωB97M-V (37) density functional) shows a differential binding energy (ΔΔEc VV10 = Ec VV10 TS-P -Ec VV10 TS-M) that favors the major product transition state for both transformations. This dispersion energy difference term is also larger in magnitude than other differential terms (ΔΔGcorr, ΔΔGsolv, ΔΔEESCF, see Table for an energetic decomposition). Other significative contributions to selectivity arise from the ΔΔGsolv (SNAr) and SCF energy (SN2) but these are smaller in magnitude than ΔΔEc VV10 and favor the minor enantiomer instead, just partly counteracting the effect of dispersion. Therefore, based on our experimental and computational studies, we envision that differential dispersion interactions have a significant influence on the selectivity of the two transformations. This heuristic is also in agreement with the experimental observation of an increase of enantioselectivity for both transformations with the increase of size (and polarizability) of substituents on the phosphine aryl rings of the catalyst (see Figure for catalyst optimization data).