Just because a reaction is thermodynamically favored does not mean it is spontaneous. I didn't neglect the role of temperature, but meant to leave it as the open variable of sorts; partly thinking that standard conditions might provide the required activation energy.
-On what order
is the activation energy for this reaction?
-What is the mechanism anyway (to iodoephedrine)? Sn2? Sn1?
(It feels like it'd have to be somehow in-between.. Inversion indicates Sn2, but with an aweful OH- leaving group?? Sn1 would make for water as the leaving group, but it's trigonal bipyramidal transition state would cause racemization, no? I'm probably forgetting..) Then, couldn't any eliminations undergo a methyl shift?
-Just how much energy is ambiently 'free' at STP?
-If the reaction was perfectly insulated, beyond the initial energy of activation, wouldn't it be self-sustaining (- since even the EA would be conserved)?
-Given the observation that it IS indeed spontaneous at RT(initially anyways), might conservation of the energy from rxnA drive rxnB? (-whether by insulation or perhaps coupling the two parts in lock-step somehow..)
If I am completely off-base, you don't have to give me a chemistry lesson (unless you want to), just tell me I'm wrong and I'll work my way out..