Direct measurement of the energy barrier for 1,2-chlorine atom migration in α-methyl-α-chlorobenzyl (Chloro) crbene
Liu, Michael T. H.Chateauneuf, J. E.
Journal of Physical Organic Chemistry
The first direct determination of a 1,2-chlorine atom shift in a chlorobenzylcarbene was achieved by nanosecond laser flash photolysis. Arrhenius activation parameters of E(act) = 3.39 +/- 0.14 kcal mol-1 and log [A(s-1)] = 10.98 +/- 0.14 were obtained for 1,2-chlorine migration in alpha-methyl-alpha-chlorobenzyl(chloro)carbene. The lifetime of this carbene is considerably longer than previously estimated and the measured E(act) is in excellent agreement with that determined by product analysis.