These rearrangements do not occur for obvious reasons in the E2 reaction.

What happens in an E2 reaction?

The most common mechanism for dehydrohalogenation is the E2 mechanism. The reaction is concerted—all bonds are broken and formed in a single step. E2 reactions are regioselective and favor the formation of Zaitsev products. 2 mechanisms in how the identity of the base, the leaving group and the solvent affect the rate.

Is there rearrangement in E1?

In an E1 reaction, the rate determining step is the loss of the leaving group to form the intermediate carbocation. ... Since carbocation intermediates are formed during an E1, there is always the possibility of rearrangements (e.g. 1,2-hydride or 1,2-alkyl shifts) to generate a more stable carbocation.