What is the key idea behind the differences between thermal dynamic control and kinetic control?

Reacting 1,3-Butadiene and HBr at low temperatures creates a 1,2 addition product as the major product and 1,4 at higher temperatures. But why is this? Is it because the additional heat is used to overcome the activation energy?





Is the 1,2 a more stable product at the low temperature and then less stable at the high temperature? It seems to me that if it was stable at lower temperatures, wouldn't it be even more stable at the higher temperatures as in the case of the 1,4?





I'm missing some key to understanding this.What is the key idea behind the differences between thermal dynamic control and kinetic control?
You're on the right track.





http://users.ox.ac.uk/~mwalter/web_05/ye鈥?/a>


this site explains what you are talking about.





You can also get 1,4 if you use a peroxide solvent- it will form a radical. This site explains it:


http://www.cem.msu.edu/~reusch/VirtualTe鈥?/a>