Figure 4.
Plot of kobsd versus [HMPA] in 10.0 M THF/hexanes cosolvent for the rearrangement of 6b (0.004 M) by LDA (0.10 M) at -65 °C. The curve depicts an unweighted least-squares fit to kobsd = k[HMPA]n + k’ (k = (4.8 ± 0.2) × 10-3, n = 0.8 ± 0.1, k’ = (0.5 ± 0.2) × 10-3). Pseudo-first-order conditions not maintained at 0.05 M HMPA (·); data was omitted from the fit.