To gain an understanding of how the reacQon responds to changes in the electronics of the aryl bromide, a Hammee analysis was carried out. ReacQon rates acquired from separate kineQc runs for each substrate were compared. A plot of ln(kX/kH) vs sp does not fit a simple linear trend, but rather shows an inflecQon point, suggesQve of two different kineQc regimes (Fig. ).