Is there a formation of carbocation in both elimination reactions, E1 and E2?

1 Answer
Ernest Z.
Jan 10, 2015

No, a carbocation is formed only in #E1#eliminations.

In an #E1# elimination, the leaving group departs first to form an intermediate carbocation. Then a base attacks a β hydrogen in the carbocation to form the alkene.

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In an #E2# elimination, the leaving group departs at the same time as the base attacks.

There is a single transition state that consists of both the base and the substrate.

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At no time does a carbocation form in an #E2# elimination.

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