Question

What are E2 reactions?

Answer 1

First of all, an elimination reaction is a type of organic reaction in which two substituents are removed from a molecule in either a one or two-step mechanism.

• The one-step mechanism is known as the E2 reaction
• The two-step mechanism is known as the E1 reaction.

Note: The numbers do not have to do with the number of steps in the mechanism, but rather the kinetics of the reaction, bimolecular and unimolecular respectively.

What is E2 mechanism?

• E2 is the first step of elimination with a single transition state .

• Typically undergone by primary substituted alkyl halides, but is possible with some secondary alkyl halides.

• The reaction rate is second order.
• E2 typically uses a strong base, it needs a chemical strong enough to pull off a weakly acidic hydrogen.
• E2 competes with the SN2 reaction mechanism.