Fig. 9. Testing the predictive capability of electronic structure models against compounds which undergo selective VCPR or [3,3]-rearrangement (simplified computational models were used for 50 (Ts replaced with Ms) and 52 (TBS replaced with TMS)). Free energies of activation (ΔG ‡) calculated on Gaussian'09 using UB3LYP/6-31G* (gas phase, 298 K) and quoted in kcal mol–1. Predicted temperature derived from the straight line equation y = 0.0721x + 2.0341 from a plot of corrected ΔG‡B3LYP against VCPR rearrangement temperatures (see ESI†).
