To further examine the steric impact of the extended ligand structure on ∆∆E R X , we analyze the modified complexes without phenyl groups, shown in Figure . Removing the phenyl groups only slightly alters the bite angles compared to the full ligands (about 1 -2 • difference, see Table of the SI). The altered ∆∆E R X values are plotted in Figure , along with values for the full complexes and the corresponding minimal models. If the bite angle were the principal descriptor of reactivity, one would expect small changes in ∆∆E R X , at least for dppm and dppb. Instead, this is only true for dppb, with ∆∆E R pb differing by no more than 2 kcal/mol for any reaction. On the other hand, the ∆∆E R pm values change much more, by 2.6 kcal/mol and 4.2 kcal/mol for R2 and R3, respectively. This indicates that the phenyl groups play a significant role in the reactivity.